Merge pull request 'feat/color-pick' (#30) from feat/color-pick into main

Reviewed-on: genewildish/Mainline#30

README.md

@@ -2,7 +2,7 @@
 
 > *Digital consciousness stream. Matrix aesthetic · THX-1138 hue.*
 
-A full-screen terminal news ticker that renders live global headlines in large OTF-font block characters with a white-hot → deep green gradient. Headlines auto-translate into the native script of their subject region. Ambient mic input warps the glitch rate in real time. A `--poetry` mode replaces the feed with public-domain literary passages. Live messages can be pushed to the display over [ntfy.sh](https://ntfy.sh).
+A full-screen terminal news ticker that renders live global headlines in large OTF-font block characters with selectable color gradients (Verdant Green, Molten Orange, or Violet Purple). Headlines auto-translate into the native script of their subject region. Ambient mic input warps the glitch rate in real time. A `--poetry` mode replaces the feed with public-domain literary passages. Live messages can be pushed to the display over [ntfy.sh](https://ntfy.sh).
 
 ---
 
@@ -68,6 +68,21 @@ Navigation: `↑`/`↓` or `j`/`k` to move, `Enter` or `q` to select. The select
 
 To add your own fonts, drop `.otf`, `.ttf`, or `.ttc` files into `fonts/` (or point `--font-dir` at any other folder). Font collections (`.ttc`, multi-face `.otf`) are enumerated face-by-face.
 
+### Color Schemes
+
+Mainline supports three color themes for the scrolling gradient: **Verdant Green**, **Molten Orange**, and **Violet Purple**. Each theme uses a precise color-opposite palette for ntfy message queue rendering (magenta, blue, and yellow respectively).
+
+On startup, an interactive picker presents all available color schemes:
+```
+  [1] Verdant Green    (white-hot → deep green)
+  [2] Molten Orange    (white-hot → deep orange)
+  [3] Violet Purple    (white-hot → deep purple)
+```
+
+Navigation: `↑`/`↓` or `j`/`k` to move, `Enter` or `q` to select. The selection applies only to the current session; you'll pick a fresh theme each run.
+
+**Note:** The boot UI (title, status lines, font picker menu) uses a hardcoded green accent color for visual continuity. Only the scrolling headlines and incoming messages render in the selected theme gradient.
+
 ### ntfy.sh
 
 Mainline polls a configurable ntfy.sh topic in the background. When a message arrives, the scroll pauses and the message renders full-screen for `MESSAGE_DISPLAY_SECS` seconds, then the stream resumes.

docs/superpowers/plans/2026-03-16-color-scheme-implementation.md

@@ -0,0 +1,894 @@
+# Color Scheme Switcher Implementation Plan
+
+> **For agentic workers:** REQUIRED: Use superpowers:subagent-driven-development (if subagents available) or superpowers:executing-plans to implement this plan. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Implement interactive color theme picker at startup that lets users choose between green, orange, or purple gradients with complementary message queue colors.
+
+**Architecture:** New `themes.py` data module defines Theme class and THEME_REGISTRY. Config adds `ACTIVE_THEME` global set by picker. Render functions read from active theme instead of hardcoded constants. App adds picker UI that mirrors font picker pattern.
+
+**Tech Stack:** Python 3.10+, ANSI 256-color codes, existing terminal I/O utilities
+
+---
+
+## File Structure
+
+| File | Purpose | Change Type |
+|------|---------|------------|
+| `engine/themes.py` | Theme class, THEME_REGISTRY, color codes | Create |
+| `engine/config.py` | ACTIVE_THEME global, set_active_theme() | Modify |
+| `engine/render.py` | Replace GRAD_COLS/MSG_GRAD_COLS with config lookup | Modify |
+| `engine/scroll.py` | Update message gradient call | Modify |
+| `engine/app.py` | pick_color_theme(), call in main() | Modify |
+| `tests/test_themes.py` | Theme class and registry unit tests | Create |
+
+---
+
+## Chunk 1: Theme Data Module
+
+### Task 1: Create themes.py with Theme class and registry
+
+**Files:**
+- Create: `engine/themes.py`
+- Test: `tests/test_themes.py`
+
+- [ ] **Step 1: Write failing test for Theme class**
+
+Create `tests/test_themes.py`:
+
+```python
+"""Test color themes and registry."""
+from engine.themes import Theme, THEME_REGISTRY, get_theme
+
+
+def test_theme_construction():
+    """Theme stores name and gradient lists."""
+    main = ["\033[1;38;5;231m"] * 12
+    msg = ["\033[1;38;5;225m"] * 12
+    theme = Theme(name="Test Green", main_gradient=main, message_gradient=msg)
+
+    assert theme.name == "Test Green"
+    assert theme.main_gradient == main
+    assert theme.message_gradient == msg
+
+
+def test_gradient_length():
+    """Each gradient must have exactly 12 ANSI codes."""
+    for theme_id, theme in THEME_REGISTRY.items():
+        assert len(theme.main_gradient) == 12, f"{theme_id} main gradient wrong length"
+        assert len(theme.message_gradient) == 12, f"{theme_id} message gradient wrong length"
+
+
+def test_theme_registry_has_three_themes():
+    """Registry contains green, orange, purple."""
+    assert len(THEME_REGISTRY) == 3
+    assert "green" in THEME_REGISTRY
+    assert "orange" in THEME_REGISTRY
+    assert "purple" in THEME_REGISTRY
+
+
+def test_get_theme_valid():
+    """get_theme returns Theme object for valid ID."""
+    theme = get_theme("green")
+    assert isinstance(theme, Theme)
+    assert theme.name == "Verdant Green"
+
+
+def test_get_theme_invalid():
+    """get_theme raises KeyError for invalid ID."""
+    with pytest.raises(KeyError):
+        get_theme("invalid_theme")
+
+
+def test_green_theme_unchanged():
+    """Green theme uses original green → magenta colors."""
+    green_theme = get_theme("green")
+    # First color should be white (bold)
+    assert green_theme.main_gradient[0] == "\033[1;38;5;231m"
+    # Last deep green
+    assert green_theme.main_gradient[9] == "\033[38;5;22m"
+    # Message gradient is magenta
+    assert green_theme.message_gradient[9] == "\033[38;5;89m"
+```
+
+Run: `pytest tests/test_themes.py -v`
+Expected: FAIL (module doesn't exist)
+
+- [ ] **Step 2: Create themes.py with Theme class and finalized gradients**
+
+Create `engine/themes.py`:
+
+```python
+"""Color theme definitions and registry."""
+from typing import Optional
+
+
+class Theme:
+    """Encapsulates a color scheme: name, main gradient, message gradient."""
+
+    def __init__(self, name: str, main_gradient: list[str], message_gradient: list[str]):
+        """Initialize theme with display name and gradient lists.
+
+        Args:
+            name: Display name (e.g., "Verdant Green")
+            main_gradient: List of 12 ANSI 256-color codes (white → primary color)
+            message_gradient: List of 12 ANSI codes (white → complementary color)
+        """
+        self.name = name
+        self.main_gradient = main_gradient
+        self.message_gradient = message_gradient
+
+
+# ─── FINALIZED GRADIENTS ──────────────────────────────────────────────────
+# Each gradient: white → primary/complementary, 12 steps total
+# Format: "\033[<brightness>;<color>m" where color is 38;5;<colorcode>
+
+_GREEN_MAIN = [
+    "\033[1;38;5;231m",  # white (bold)
+    "\033[1;38;5;195m",  # pale white-tint
+    "\033[38;5;123m",    # bright cyan
+    "\033[38;5;118m",    # bright lime
+    "\033[38;5;82m",     # lime
+    "\033[38;5;46m",     # bright green
+    "\033[38;5;40m",     # green
+    "\033[38;5;34m",     # medium green
+    "\033[38;5;28m",     # dark green
+    "\033[38;5;22m",     # deep green
+    "\033[2;38;5;22m",   # dim deep green
+    "\033[2;38;5;235m",  # near black
+]
+
+_GREEN_MESSAGE = [
+    "\033[1;38;5;231m",  # white (bold)
+    "\033[1;38;5;225m",  # pale pink-white
+    "\033[38;5;219m",    # bright pink
+    "\033[38;5;213m",    # hot pink
+    "\033[38;5;207m",    # magenta
+    "\033[38;5;201m",    # bright magenta
+    "\033[38;5;165m",    # orchid-red
+    "\033[38;5;161m",    # ruby-magenta
+    "\033[38;5;125m",    # dark magenta
+    "\033[38;5;89m",     # deep maroon-magenta
+    "\033[2;38;5;89m",   # dim deep maroon-magenta
+    "\033[2;38;5;235m",  # near black
+]
+
+_ORANGE_MAIN = [
+    "\033[1;38;5;231m",  # white (bold)
+    "\033[1;38;5;215m",  # pale orange-white
+    "\033[38;5;209m",    # bright orange
+    "\033[38;5;208m",    # vibrant orange
+    "\033[38;5;202m",    # orange
+    "\033[38;5;166m",    # dark orange
+    "\033[38;5;130m",    # burnt orange
+    "\033[38;5;94m",     # rust
+    "\033[38;5;58m",     # dark rust
+    "\033[38;5;94m",     # rust (hold)
+    "\033[2;38;5;94m",   # dim rust
+    "\033[2;38;5;235m",  # near black
+]
+
+_ORANGE_MESSAGE = [
+    "\033[1;38;5;231m",  # white (bold)
+    "\033[1;38;5;195m",  # pale cyan-white
+    "\033[38;5;33m",     # bright blue
+    "\033[38;5;27m",     # blue
+    "\033[38;5;21m",     # deep blue
+    "\033[38;5;21m",     # deep blue (hold)
+    "\033[38;5;21m",     # deep blue (hold)
+    "\033[38;5;18m",     # navy
+    "\033[38;5;18m",     # navy (hold)
+    "\033[38;5;18m",     # navy (hold)
+    "\033[2;38;5;18m",   # dim navy
+    "\033[2;38;5;235m",  # near black
+]
+
+_PURPLE_MAIN = [
+    "\033[1;38;5;231m",  # white (bold)
+    "\033[1;38;5;225m",  # pale purple-white
+    "\033[38;5;177m",    # bright purple
+    "\033[38;5;171m",    # vibrant purple
+    "\033[38;5;165m",    # purple
+    "\033[38;5;135m",    # medium purple
+    "\033[38;5;129m",    # purple
+    "\033[38;5;93m",     # dark purple
+    "\033[38;5;57m",     # deep purple
+    "\033[38;5;57m",     # deep purple (hold)
+    "\033[2;38;5;57m",   # dim deep purple
+    "\033[2;38;5;235m",  # near black
+]
+
+_PURPLE_MESSAGE = [
+    "\033[1;38;5;231m",  # white (bold)
+    "\033[1;38;5;226m",  # pale yellow-white
+    "\033[38;5;226m",    # bright yellow
+    "\033[38;5;220m",    # yellow
+    "\033[38;5;220m",    # yellow (hold)
+    "\033[38;5;184m",    # dark yellow
+    "\033[38;5;184m",    # dark yellow (hold)
+    "\033[38;5;178m",    # olive-yellow
+    "\033[38;5;178m",    # olive-yellow (hold)
+    "\033[38;5;172m",    # golden
+    "\033[2;38;5;172m",  # dim golden
+    "\033[2;38;5;235m",  # near black
+]
+
+# ─── THEME REGISTRY ───────────────────────────────────────────────────────
+
+THEME_REGISTRY = {
+    "green": Theme(
+        name="Verdant Green",
+        main_gradient=_GREEN_MAIN,
+        message_gradient=_GREEN_MESSAGE,
+    ),
+    "orange": Theme(
+        name="Molten Orange",
+        main_gradient=_ORANGE_MAIN,
+        message_gradient=_ORANGE_MESSAGE,
+    ),
+    "purple": Theme(
+        name="Violet Purple",
+        main_gradient=_PURPLE_MAIN,
+        message_gradient=_PURPLE_MESSAGE,
+    ),
+}
+
+
+def get_theme(theme_id: str) -> Theme:
+    """Retrieve a theme by ID.
+
+    Args:
+        theme_id: One of "green", "orange", "purple"
+
+    Returns:
+        Theme object
+
+    Raises:
+        KeyError: If theme_id not found in registry
+    """
+    if theme_id not in THEME_REGISTRY:
+        raise KeyError(f"Unknown theme: {theme_id}. Available: {list(THEME_REGISTRY.keys())}")
+    return THEME_REGISTRY[theme_id]
+```
+
+- [ ] **Step 3: Run tests to verify they pass**
+
+Run: `pytest tests/test_themes.py -v`
+Expected: PASS (all 6 tests)
+
+- [ ] **Step 4: Commit**
+
+```bash
+git add engine/themes.py tests/test_themes.py
+git commit -m "feat: create Theme class and registry with finalized color gradients
+
+- Define Theme class to encapsulate name and main/message gradients
+- Create THEME_REGISTRY with green, orange, purple themes
+- Each gradient has 12 ANSI 256-color codes finalized
+- Complementary color pairs: green/magenta, orange/blue, purple/yellow
+- Add get_theme() lookup with error handling
+- Add comprehensive unit tests"
+```
+
+---
+
+## Chunk 2: Config Integration
+
+### Task 2: Add ACTIVE_THEME global and set_active_theme() to config.py
+
+**Files:**
+- Modify: `engine/config.py:1-30`
+- Test: `tests/test_config.py` (expand existing)
+
+- [ ] **Step 1: Write failing tests for config changes**
+
+Add to `tests/test_config.py`:
+
+```python
+def test_active_theme_initially_none():
+    """ACTIVE_THEME is None before initialization."""
+    # This test may fail if config is already initialized
+    # We'll set it to None first for testing
+    import engine.config
+    engine.config.ACTIVE_THEME = None
+    assert engine.config.ACTIVE_THEME is None
+
+
+def test_set_active_theme_green():
+    """set_active_theme('green') sets ACTIVE_THEME to green theme."""
+    from engine.config import set_active_theme
+    from engine.themes import get_theme
+
+    set_active_theme("green")
+
+    assert config.ACTIVE_THEME is not None
+    assert config.ACTIVE_THEME.name == "Verdant Green"
+    assert config.ACTIVE_THEME == get_theme("green")
+
+
+def test_set_active_theme_default():
+    """set_active_theme() with no args defaults to green."""
+    from engine.config import set_active_theme
+
+    set_active_theme()
+
+    assert config.ACTIVE_THEME.name == "Verdant Green"
+
+
+def test_set_active_theme_invalid():
+    """set_active_theme() with invalid ID raises KeyError."""
+    from engine.config import set_active_theme
+
+    with pytest.raises(KeyError):
+        set_active_theme("invalid")
+```
+
+Run: `pytest tests/test_config.py -v`
+Expected: FAIL (functions don't exist yet)
+
+- [ ] **Step 2: Add ACTIVE_THEME global and set_active_theme() to config.py**
+
+Edit `engine/config.py`, add after line 30 (after `_resolve_font_path` function):
+
+```python
+# ─── COLOR THEME ──────────────────────────────────────────────────────────
+ACTIVE_THEME = None  # set by set_active_theme() after picker
+
+
+def set_active_theme(theme_id: str = "green"):
+    """Set the active color theme. Defaults to 'green' if not specified.
+
+    Args:
+        theme_id: One of "green", "orange", "purple"
+
+    Raises:
+        KeyError: If theme_id is invalid
+    """
+    global ACTIVE_THEME
+    from engine import themes
+    ACTIVE_THEME = themes.get_theme(theme_id)
+```
+
+- [ ] **Step 3: Remove hardcoded GRAD_COLS and MSG_GRAD_COLS from render.py**
+
+Edit `engine/render.py`, find and delete lines 20-49 (the hardcoded gradient arrays):
+
+```python
+# DELETED:
+# GRAD_COLS = [...]
+# MSG_GRAD_COLS = [...]
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `pytest tests/test_config.py::test_active_theme_initially_none -v`
+Run: `pytest tests/test_config.py::test_set_active_theme_green -v`
+Run: `pytest tests/test_config.py::test_set_active_theme_default -v`
+Run: `pytest tests/test_config.py::test_set_active_theme_invalid -v`
+
+Expected: PASS (all 4 new tests)
+
+- [ ] **Step 5: Verify existing config tests still pass**
+
+Run: `pytest tests/test_config.py -v`
+
+Expected: PASS (all existing + new tests)
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add engine/config.py tests/test_config.py
+git commit -m "feat: add ACTIVE_THEME global and set_active_theme() to config
+
+- Add ACTIVE_THEME global (initialized to None)
+- Add set_active_theme(theme_id) function with green default
+- Remove hardcoded GRAD_COLS and MSG_GRAD_COLS (move to themes.py)
+- Add comprehensive tests for theme setting"
+```
+
+---
+
+## Chunk 3: Render Pipeline Integration
+
+### Task 3: Update render.py to use config.ACTIVE_THEME
+
+**Files:**
+- Modify: `engine/render.py:15-220`
+- Test: `tests/test_render.py` (expand existing)
+
+- [ ] **Step 1: Write failing test for lr_gradient with theme**
+
+Add to `tests/test_render.py`:
+
+```python
+def test_lr_gradient_uses_active_theme(monkeypatch):
+    """lr_gradient uses config.ACTIVE_THEME when cols=None."""
+    from engine import config, render
+    from engine.themes import get_theme
+
+    # Set orange theme
+    config.set_active_theme("orange")
+
+    # Create simple rows
+    rows = ["test row"]
+    result = render.lr_gradient(rows, offset=0, cols=None)
+
+    # Result should start with first color from orange main gradient
+    assert result[0].startswith("\033[1;38;5;231m")  # white (same for all)
+
+
+def test_lr_gradient_fallback_when_no_theme(monkeypatch):
+    """lr_gradient uses fallback when ACTIVE_THEME is None."""
+    from engine import config, render
+
+    # Clear active theme
+    config.ACTIVE_THEME = None
+
+    rows = ["test row"]
+    result = render.lr_gradient(rows, offset=0, cols=None)
+
+    # Should not crash and should return something
+    assert result is not None
+    assert len(result) > 0
+
+
+def test_default_green_gradient_length():
+    """_default_green_gradient returns 12 colors."""
+    from engine import render
+
+    colors = render._default_green_gradient()
+    assert len(colors) == 12
+```
+
+Run: `pytest tests/test_render.py::test_lr_gradient_uses_active_theme -v`
+Expected: FAIL (function signature doesn't match)
+
+- [ ] **Step 2: Update lr_gradient() to use config.ACTIVE_THEME**
+
+Edit `engine/render.py`, find the `lr_gradient()` function (around line 194) and update it:
+
+```python
+def lr_gradient(rows, offset, cols=None):
+    """
+    Render rows through a left-to-right color sweep.
+
+    Args:
+        rows: List of text rows to colorize
+        offset: Gradient position offset (for animation)
+        cols: Optional list of color codes. If None, uses active theme.
+
+    Returns:
+        List of colorized rows
+    """
+    if cols is None:
+        from engine import config
+        cols = (
+            config.ACTIVE_THEME.main_gradient
+            if config.ACTIVE_THEME
+            else _default_green_gradient()
+        )
+
+    # ... rest of function unchanged ...
+```
+
+- [ ] **Step 3: Add _default_green_gradient() fallback function**
+
+Add to `engine/render.py` before `lr_gradient()`:
+
+```python
+def _default_green_gradient():
+    """Fallback green gradient (original colors) for initialization."""
+    return [
+        "\033[1;38;5;231m",  # white (bold)
+        "\033[1;38;5;195m",  # pale white-tint
+        "\033[38;5;123m",    # bright cyan
+        "\033[38;5;118m",    # bright lime
+        "\033[38;5;82m",     # lime
+        "\033[38;5;46m",     # bright green
+        "\033[38;5;40m",     # green
+        "\033[38;5;34m",     # medium green
+        "\033[38;5;28m",     # dark green
+        "\033[38;5;22m",     # deep green
+        "\033[2;38;5;22m",   # dim deep green
+        "\033[2;38;5;235m",  # near black
+    ]
+
+
+def _default_magenta_gradient():
+    """Fallback magenta gradient (original message colors) for initialization."""
+    return [
+        "\033[1;38;5;231m",  # white (bold)
+        "\033[1;38;5;225m",  # pale pink-white
+        "\033[38;5;219m",    # bright pink
+        "\033[38;5;213m",    # hot pink
+        "\033[38;5;207m",    # magenta
+        "\033[38;5;201m",    # bright magenta
+        "\033[38;5;165m",    # orchid-red
+        "\033[38;5;161m",    # ruby-magenta
+        "\033[38;5;125m",    # dark magenta
+        "\033[38;5;89m",     # deep maroon-magenta
+        "\033[2;38;5;89m",   # dim deep maroon-magenta
+        "\033[2;38;5;235m",  # near black
+    ]
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `pytest tests/test_render.py::test_lr_gradient_uses_active_theme -v`
+Run: `pytest tests/test_render.py::test_lr_gradient_fallback_when_no_theme -v`
+Run: `pytest tests/test_render.py::test_default_green_gradient_length -v`
+
+Expected: PASS (all 3 new tests)
+
+- [ ] **Step 5: Run full render test suite**
+
+Run: `pytest tests/test_render.py -v`
+
+Expected: PASS (existing tests may need adjustment for mocking)
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add engine/render.py tests/test_render.py
+git commit -m "feat: update lr_gradient to use config.ACTIVE_THEME
+
+- Update lr_gradient(cols=None) to check config.ACTIVE_THEME
+- Add _default_green_gradient() and _default_magenta_gradient() fallbacks
+- Fallback used when ACTIVE_THEME is None (non-interactive init)
+- Add tests for theme-aware and fallback gradient rendering"
+```
+
+---
+
+## Chunk 4: Message Gradient Integration
+
+### Task 4: Update scroll.py to use message gradient from config
+
+**Files:**
+- Modify: `engine/scroll.py:85-95`
+- Test: existing `tests/test_scroll.py`
+
+- [ ] **Step 1: Locate message gradient calls in scroll.py**
+
+Run: `grep -n "MSG_GRAD_COLS\|lr_gradient_opposite" /Users/genejohnson/Dev/mainline/engine/scroll.py`
+
+Expected: Should find line(s) where `MSG_GRAD_COLS` or similar is used
+
+- [ ] **Step 2: Update scroll.py to use theme message gradient**
+
+Edit `engine/scroll.py`, find the line that uses message gradients (around line 89 based on spec) and update:
+
+Old code:
+```python
+# Some variation of:
+rows = lr_gradient(rows, offset, MSG_GRAD_COLS)
+```
+
+New code:
+```python
+from engine import config
+msg_cols = (
+    config.ACTIVE_THEME.message_gradient
+    if config.ACTIVE_THEME
+    else render._default_magenta_gradient()
+)
+rows = lr_gradient(rows, offset, msg_cols)
+```
+
+Or use the helper approach (create `msg_gradient()` in render.py):
+
+```python
+def msg_gradient(rows, offset):
+    """Apply message (ntfy) gradient using theme complementary colors."""
+    from engine import config
+    cols = (
+        config.ACTIVE_THEME.message_gradient
+        if config.ACTIVE_THEME
+        else _default_magenta_gradient()
+    )
+    return lr_gradient(rows, offset, cols)
+```
+
+Then in scroll.py:
+```python
+rows = render.msg_gradient(rows, offset)
+```
+
+- [ ] **Step 3: Run existing scroll tests**
+
+Run: `pytest tests/test_scroll.py -v`
+
+Expected: PASS (existing functionality unchanged)
+
+- [ ] **Step 4: Commit**
+
+```bash
+git add engine/scroll.py engine/render.py
+git commit -m "feat: update scroll.py to use theme message gradient
+
+- Replace MSG_GRAD_COLS reference with config.ACTIVE_THEME.message_gradient
+- Use fallback magenta gradient when theme not initialized
+- Ensure ntfy messages render in complementary color from selected theme"
+```
+
+---
+
+## Chunk 5: Color Picker UI
+
+### Task 5: Create pick_color_theme() function in app.py
+
+**Files:**
+- Modify: `engine/app.py:1-300`
+- Test: manual/integration (interactive)
+
+- [ ] **Step 1: Write helper functions for color picker UI**
+
+Edit `engine/app.py`, add before `pick_font_face()` function:
+
+```python
+def _draw_color_picker(themes_list, selected):
+    """Draw the color theme picker menu."""
+    import sys
+    from engine.terminal import CLR, W_GHOST, G_HI, G_DIM, tw
+
+    print(CLR, end="")
+    print()
+    print(f"  {G_HI}▼ COLOR THEME{W_GHOST} ─ ↑/↓ or j/k to move, Enter/q to select{G_DIM}")
+    print(f"  {W_GHOST}{'─' * (tw() - 4)}\n")
+
+    for i, (theme_id, theme) in enumerate(themes_list):
+        prefix = "  ▶ " if i == selected else "    "
+        color = G_HI if i == selected else ""
+        reset = "" if i == selected else W_GHOST
+        print(f"{prefix}{color}{theme.name}{reset}")
+
+    print()
+```
+
+- [ ] **Step 2: Create pick_color_theme() function**
+
+Edit `engine/app.py`, add after helper function:
+
+```python
+def pick_color_theme():
+    """Interactive color theme picker. Defaults to 'green' if not TTY."""
+    import sys
+    import termios
+    import tty
+    from engine import config, themes
+
+    # Non-interactive fallback: use green
+    if not sys.stdin.isatty():
+        config.set_active_theme("green")
+        return
+
+    themes_list = list(themes.THEME_REGISTRY.items())
+    selected = 0
+
+    fd = sys.stdin.fileno()
+    old_settings = termios.tcgetattr(fd)
+    try:
+        tty.setcbreak(fd)
+        while True:
+            _draw_color_picker(themes_list, selected)
+            key = _read_picker_key()
+            if key == "up":
+                selected = max(0, selected - 1)
+            elif key == "down":
+                selected = min(len(themes_list) - 1, selected + 1)
+            elif key == "enter":
+                break
+            elif key == "interrupt":
+                raise KeyboardInterrupt
+    finally:
+        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
+
+    selected_theme_id = themes_list[selected][0]
+    config.set_active_theme(selected_theme_id)
+
+    theme_name = themes_list[selected][1].name
+    print(f"  {G_DIM}> using {theme_name}{RST}")
+    time.sleep(0.8)
+    print(CLR, end="")
+    print(CURSOR_OFF, end="")
+    print()
+```
+
+- [ ] **Step 3: Update main() to call pick_color_theme() before pick_font_face()**
+
+Edit `engine/app.py`, find the `main()` function and locate where `pick_font_face()` is called (around line 265). Add before it:
+
+```python
+def main():
+    # ... existing signal handler setup ...
+
+    pick_color_theme()  # NEW LINE - before font picker
+    pick_font_face()
+
+    # ... rest of main unchanged ...
+```
+
+- [ ] **Step 4: Manual test - run in interactive terminal**
+
+Run: `python3 mainline.py`
+
+Expected:
+- See color theme picker menu before font picker
+- Can navigate with ↑/↓ or j/k
+- Can select with Enter or q
+- Selected theme applies to scrolling headlines
+- Can select different themes and see colors change
+
+- [ ] **Step 5: Manual test - run in non-interactive environment**
+
+Run: `echo "" | python3 mainline.py`
+
+Expected:
+- No color picker menu shown
+- Defaults to green theme
+- App runs without error
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add engine/app.py
+git commit -m "feat: add pick_color_theme() UI and integration
+
+- Create _draw_color_picker() to render menu
+- Create pick_color_theme() function mirroring font picker pattern
+- Integrate into main() before font picker
+- Fallback to green theme in non-interactive environments
+- Support arrow keys and j/k navigation"
+```
+
+---
+
+## Chunk 6: Integration & Validation
+
+### Task 6: End-to-end testing and cleanup
+
+**Files:**
+- Test: All modified files
+- Verify: App functionality
+
+- [ ] **Step 1: Run full test suite**
+
+Run: `pytest tests/ -v`
+
+Expected: PASS (all tests, including new ones)
+
+- [ ] **Step 2: Run linter**
+
+Run: `ruff check engine/ mainline.py`
+
+Expected: No errors (fix any style issues)
+
+- [ ] **Step 3: Manual integration test - green theme**
+
+Run: `python3 mainline.py`
+
+Then select "Verdant Green" from picker.
+
+Expected:
+- Headlines render in green → deep green
+- ntfy messages render in magenta gradient
+- Both work correctly during streaming
+
+- [ ] **Step 4: Manual integration test - orange theme**
+
+Run: `python3 mainline.py`
+
+Then select "Molten Orange" from picker.
+
+Expected:
+- Headlines render in orange → deep orange
+- ntfy messages render in blue gradient
+- Colors are visually distinct from green
+
+- [ ] **Step 5: Manual integration test - purple theme**
+
+Run: `python3 mainline.py`
+
+Then select "Violet Purple" from picker.
+
+Expected:
+- Headlines render in purple → deep purple
+- ntfy messages render in yellow gradient
+- Colors are visually distinct from green and orange
+
+- [ ] **Step 6: Test poetry mode with color picker**
+
+Run: `python3 mainline.py --poetry`
+
+Then select "orange" from picker.
+
+Expected:
+- Poetry mode works with color picker
+- Colors apply to poetry rendering
+
+- [ ] **Step 7: Test code mode with color picker**
+
+Run: `python3 mainline.py --code`
+
+Then select "purple" from picker.
+
+Expected:
+- Code mode works with color picker
+- Colors apply to code rendering
+
+- [ ] **Step 8: Verify acceptance criteria**
+
+✓ Color picker displays 3 theme options at startup
+✓ Selection applies to all headline and message gradients
+✓ Boot UI (title, status) uses hardcoded green (not theme)
+✓ Scrolling headlines and ntfy messages use theme gradients
+✓ No persistence between runs (each run picks fresh)
+✓ Non-TTY environments default to green without error
+✓ Architecture supports future random/animation modes
+✓ All gradient color codes finalized with no TBD values
+
+- [ ] **Step 9: Final commit**
+
+```bash
+git add -A
+git commit -m "feat: color scheme switcher implementation complete
+
+Closes color-pick feature with:
+- Three selectable color themes (green, orange, purple)
+- Interactive menu at startup (mirrors font picker UI)
+- Complementary colors for ntfy message queue
+- Fallback to green in non-interactive environments
+- All tests passing, manual validation complete"
+```
+
+- [ ] **Step 10: Create feature branch PR summary**
+
+```
+## Color Scheme Switcher
+
+Implements interactive color theme selection for Mainline news ticker.
+
+### What's New
+- 3 color themes: Verdant Green, Molten Orange, Violet Purple
+- Interactive picker at startup (↑/↓ or j/k, Enter to select)
+- Complementary gradients for ntfy messages (magenta, blue, yellow)
+- Fresh theme selection each run (no persistence)
+
+### Files Changed
+- `engine/themes.py` (new)
+- `engine/config.py` (ACTIVE_THEME, set_active_theme)
+- `engine/render.py` (theme-aware gradients)
+- `engine/scroll.py` (message gradient integration)
+- `engine/app.py` (pick_color_theme UI)
+- `tests/test_themes.py` (new theme tests)
+- `README.md` (documentation)
+
+### Acceptance Criteria
+All met. App fully tested and ready for merge.
+```
+
+---
+
+## Testing Checklist
+
+- [ ] Unit tests: `pytest tests/test_themes.py -v`
+- [ ] Unit tests: `pytest tests/test_config.py -v`
+- [ ] Unit tests: `pytest tests/test_render.py -v`
+- [ ] Full suite: `pytest tests/ -v`
+- [ ] Linting: `ruff check engine/ mainline.py`
+- [ ] Manual: Green theme selection
+- [ ] Manual: Orange theme selection
+- [ ] Manual: Purple theme selection
+- [ ] Manual: Poetry mode with colors
+- [ ] Manual: Code mode with colors
+- [ ] Manual: Non-TTY fallback
+
+---
+
+## Notes
+
+- `themes.py` is data-only; never import config or render to prevent cycles
+- `ACTIVE_THEME` initialized to None; guaranteed non-None before stream() via pick_color_theme()
+- Font picker UI remains hardcoded green; title/subtitle use G_HI/G_DIM constants (not theme)
+- Message gradients use complementary colors; lookup in scroll.py
+- Each gradient has 12 colors; verify length in tests
+- No persistence; fresh picker each run

docs/superpowers/specs/2026-03-16-color-scheme-design.md

@@ -0,0 +1,299 @@
+# Color Scheme Switcher Design
+
+**Date:** 2026-03-16
+**Status:** Revised after review
+**Scope:** Interactive color theme selection for Mainline news ticker
+
+---
+
+## Overview
+
+Mainline currently renders news headlines with a fixed white-hot → deep green gradient. This feature adds an interactive theme picker at startup that lets users choose between three precise color schemes (green, orange, purple), each with complementary message queue colors.
+
+The implementation uses a dedicated `Theme` class to encapsulate gradients and metadata, enabling future extensions like random rotation, animation, or additional themes without architectural changes.
+
+---
+
+## Requirements
+
+**Functional:**
+1. User selects a color theme from an interactive menu at startup (green, orange, or purple)
+2. Main headline gradient uses the selected primary color (white → color)
+3. Message queue (ntfy) gradient uses the precise complementary color (white → opposite)
+4. Selection is fresh each run (no persistence)
+5. Design supports future "random rotation" mode without refactoring
+
+**Complementary colors (precise opposites):**
+- Green (38;5;22) → Magenta (38;5;89) *(current, unchanged)*
+- Orange (38;5;208) → Blue (38;5;21)
+- Purple (38;5;129) → Yellow (38;5;226)
+
+**Non-functional:**
+- Reuse the existing font picker pattern for UI consistency
+- Zero runtime overhead during streaming (theme lookup happens once at startup)
+- **Boot UI (title, subtitle, status lines) use hardcoded green color constants (G_HI, G_DIM, G_MID); only scrolling headlines and ntfy messages use theme gradients**
+- Font picker UI remains hardcoded green for visual continuity
+
+---
+
+## Architecture
+
+### New Module: `engine/themes.py`
+
+**Data-only module:** Contains Theme class, THEME_REGISTRY, and get_theme() function. **Imports only typing; does NOT import config or render** to prevent circular dependencies.
+
+```python
+class Theme:
+    """Encapsulates a color scheme: name, main gradient, message gradient."""
+
+    def __init__(self, name: str, main_gradient: list[str], message_gradient: list[str]):
+        self.name = name
+        self.main_gradient = main_gradient      # white → primary color
+        self.message_gradient = message_gradient  # white → complementary
+```
+
+**Theme Registry:**
+Three instances registered by ID: `"green"`, `"orange"`, `"purple"` (IDs match menu labels for clarity).
+
+Each gradient is a list of 12 ANSI 256-color codes matching the current green gradient:
+```
+[
+    "\033[1;38;5;231m",  # white (bold)
+    "\033[1;38;5;195m",  # pale white-tint
+    "\033[38;5;123m",    # bright cyan
+    "\033[38;5;118m",    # bright lime
+    "\033[38;5;82m",     # lime
+    "\033[38;5;46m",     # bright color
+    "\033[38;5;40m",     # color
+    "\033[38;5;34m",     # medium color
+    "\033[38;5;28m",     # dark color
+    "\033[38;5;22m",     # deep color
+    "\033[2;38;5;22m",   # dim deep color
+    "\033[2;38;5;235m",  # near black
+]
+```
+
+**Finalized color codes:**
+
+**Green (primary: 22, complementary: 89)** — unchanged from current
+- Main: `[231, 195, 123, 118, 82, 46, 40, 34, 28, 22, 22(dim), 235]`
+- Messages: `[231, 225, 219, 213, 207, 201, 165, 161, 125, 89, 89(dim), 235]`
+
+**Orange (primary: 208, complementary: 21)**
+- Main: `[231, 215, 209, 208, 202, 166, 130, 94, 58, 94, 94(dim), 235]`
+- Messages: `[231, 195, 33, 27, 21, 21, 21, 18, 18, 18, 18(dim), 235]`
+
+**Purple (primary: 129, complementary: 226)**
+- Main: `[231, 225, 177, 171, 165, 135, 129, 93, 57, 57, 57(dim), 235]`
+- Messages: `[231, 226, 226, 220, 220, 184, 184, 178, 178, 172, 172(dim), 235]`
+
+**Public API:**
+- `get_theme(theme_id: str) -> Theme` — lookup by ID, raises KeyError if not found
+- `THEME_REGISTRY` — dict of all available themes (for picker)
+
+---
+
+### Modified: `engine/config.py`
+
+**New globals:**
+```python
+ACTIVE_THEME = None  # set by set_active_theme() after picker; guaranteed non-None during stream()
+```
+
+**New function:**
+```python
+def set_active_theme(theme_id: str = "green"):
+    """Set the active theme. Defaults to 'green' if not specified."""
+    global ACTIVE_THEME
+    from engine import themes
+    ACTIVE_THEME = themes.get_theme(theme_id)
+```
+
+**Behavior:**
+- Called by `app.pick_color_theme()` with user selection
+- Has default fallback to "green" for non-interactive environments (CI, testing, piped stdin)
+- Guarantees `ACTIVE_THEME` is set before any render functions are called
+
+**Removal:**
+- Delete hardcoded `GRAD_COLS` and `MSG_GRAD_COLS` constants
+
+---
+
+### Modified: `engine/render.py`
+
+**Updated gradient access in existing functions:**
+
+Current pattern (will be removed):
+```python
+GRAD_COLS = [...]  # hardcoded green
+MSG_GRAD_COLS = [...] # hardcoded magenta
+```
+
+New pattern — update `lr_gradient()` function:
+```python
+def lr_gradient(rows, offset, cols=None):
+    if cols is None:
+        from engine import config
+        cols = (config.ACTIVE_THEME.main_gradient
+                if config.ACTIVE_THEME
+                else _default_green_gradient())
+    # ... rest of function unchanged
+```
+
+**Define fallback:**
+```python
+def _default_green_gradient():
+    """Fallback green gradient (current colors)."""
+    return [
+        "\033[1;38;5;231m", "\033[1;38;5;195m", "\033[38;5;123m",
+        "\033[38;5;118m", "\033[38;5;82m", "\033[38;5;46m",
+        "\033[38;5;40m", "\033[38;5;34m", "\033[38;5;28m",
+        "\033[38;5;22m", "\033[2;38;5;22m", "\033[2;38;5;235m",
+    ]
+```
+
+**Message gradient handling:**
+
+The existing code (scroll.py line 89) calls `lr_gradient()` with `MSG_GRAD_COLS`. Change this call to:
+```python
+# Instead of: lr_gradient(rows, offset, MSG_GRAD_COLS)
+# Use:
+from engine import config
+cols = (config.ACTIVE_THEME.message_gradient
+        if config.ACTIVE_THEME
+        else _default_magenta_gradient())
+lr_gradient(rows, offset, cols)
+```
+
+or define a helper:
+```python
+def msg_gradient(rows, offset):
+    """Apply message (ntfy) gradient using theme complementary colors."""
+    from engine import config
+    cols = (config.ACTIVE_THEME.message_gradient
+            if config.ACTIVE_THEME
+            else _default_magenta_gradient())
+    return lr_gradient(rows, offset, cols)
+```
+
+---
+
+### Modified: `engine/app.py`
+
+**New function: `pick_color_theme()`**
+
+Mirrors `pick_font_face()` pattern:
+
+```python
+def pick_color_theme():
+    """Interactive color theme picker. Defaults to 'green' if not TTY."""
+    import sys
+    from engine import config, themes
+
+    # Non-interactive fallback: use default
+    if not sys.stdin.isatty():
+        config.set_active_theme("green")
+        return
+
+    # Interactive picker (similar to font picker)
+    themes_list = list(themes.THEME_REGISTRY.items())
+    selected = 0
+
+    # ... render menu, handle arrow keys j/k, ↑/↓ ...
+    # ... on Enter, call config.set_active_theme(themes_list[selected][0]) ...
+```
+
+**Placement in `main()`:**
+```python
+def main():
+    # ... signal handler setup ...
+    pick_color_theme()  # NEW — before title/subtitle
+    pick_font_face()
+    # ... rest of boot sequence, title/subtitle use hardcoded G_HI/G_DIM ...
+```
+
+**Important:** The title and subtitle render with hardcoded `G_HI`/`G_DIM` constants, not theme gradients. This is intentional for visual consistency with the font picker menu.
+
+---
+
+## Data Flow
+
+```
+User starts: mainline.py
+    ↓
+main() called
+    ↓
+pick_color_theme()
+    → If TTY: display menu, read input, call config.set_active_theme(user_choice)
+    → If not TTY: silently call config.set_active_theme("green")
+    ↓
+pick_font_face() — renders in hardcoded green UI colors
+    ↓
+Boot messages (title, status) — all use hardcoded G_HI/G_DIM (not theme gradients)
+    ↓
+stream() — headlines + ntfy messages use config.ACTIVE_THEME gradients
+    ↓
+On exit: no persistence
+```
+
+---
+
+## Implementation Notes
+
+### Initialization Guarantee
+`config.ACTIVE_THEME` is guaranteed to be non-None before `stream()` is called because:
+1. `pick_color_theme()` always sets it (either interactively or via fallback)
+2. It's called before any rendering happens
+3. Default fallback ensures non-TTY environments don't crash
+
+### Module Independence
+`themes.py` is a pure data module with no imports of `config` or `render`. This prevents circular dependencies and allows it to be imported by multiple consumers without side effects.
+
+### Color Code Finalization
+All three gradient sequences (green, orange, purple main + complementary) are now finalized with specific ANSI codes. No TBD placeholders remain.
+
+### Theme ID Naming
+IDs are `"green"`, `"orange"`, `"purple"` — matching the menu labels exactly for clarity.
+
+### Terminal Resize Handling
+The `pick_color_theme()` function mirrors `pick_font_face()`, which does not handle terminal resizing during the picker display. If the terminal is resized while the picker menu is shown, the menu redraw may be incomplete; pressing any key (arrow, j/k, q) continues normally. This is acceptable because:
+1. The picker completes quickly (< 5 seconds typical interaction)
+2. Once a theme is selected, the menu closes and rendering begins
+3. The streaming phase (`stream()`) is resilient to terminal resizing and auto-reflows to new dimensions
+
+No special resize handling is needed for the color picker beyond what exists for the font picker.
+
+### Testing Strategy
+1. **Unit tests** (`tests/test_themes.py`):
+   - Verify Theme class construction
+   - Test THEME_REGISTRY lookup (valid and invalid IDs)
+   - Confirm gradient lists have correct length (12)
+
+2. **Integration tests** (`tests/test_render.py`):
+   - Mock `config.ACTIVE_THEME` to each theme
+   - Verify `lr_gradient()` uses correct colors
+   - Verify fallback works when `ACTIVE_THEME` is None
+
+3. **Existing tests:**
+   - Render tests that check gradient output will need to mock `config.ACTIVE_THEME`
+   - Use pytest fixtures to set theme per test case
+
+---
+
+## Files Changed
+- `engine/themes.py` (new)
+- `engine/config.py` (add `ACTIVE_THEME`, `set_active_theme()`)
+- `engine/render.py` (replace GRAD_COLS/MSG_GRAD_COLS references with config lookups)
+- `engine/app.py` (add `pick_color_theme()`, call in main)
+- `tests/test_themes.py` (new unit tests)
+- `tests/test_render.py` (update mocking strategy)
+
+## Acceptance Criteria
+1. ✓ Color picker displays 3 theme options at startup
+2. ✓ Selection applies to all headline and message gradients
+3. ✓ Boot UI (title, status) uses hardcoded green (not theme)
+4. ✓ Scrolling headlines and ntfy messages use theme gradients
+5. ✓ No persistence between runs
+6. ✓ Non-TTY environments default to green without error
+7. ✓ Architecture supports future random/animation modes
+8. ✓ All gradient color codes finalized with no TBD values

engine/app.py

@@ -10,7 +10,7 @@ import termios
 import time
 import tty
 
-from engine import config, render
+from engine import config, render, themes
 from engine.fetch import fetch_all, fetch_poetry, load_cache, save_cache
 from engine.mic import MicMonitor
 from engine.ntfy import NtfyPoller
@@ -65,6 +65,30 @@ def _read_picker_key():
     return None
 
 
+def _draw_color_picker(themes_list, selected):
+    """Draw the color theme picker menu.
+
+    Args:
+        themes_list: List of (theme_id, Theme) tuples from THEME_REGISTRY.items()
+        selected: Index of currently selected theme (0-2)
+    """
+    print(CLR, end="")
+    print()
+
+    print(
+        f"  {G_HI}▼ COLOR THEME{RST} {W_GHOST}─ ↑/↓ or j/k to move, Enter/q to select{RST}"
+    )
+    print(f"  {W_GHOST}{'─' * (tw() - 4)}{RST}\n")
+
+    for i, (theme_id, theme) in enumerate(themes_list):
+        prefix = "  ▶ " if i == selected else "    "
+        color = G_HI if i == selected else ""
+        reset = "" if i == selected else W_GHOST
+        print(f"{prefix}{color}{theme.name}{reset}")
+
+    print()
+
+
 def _normalize_preview_rows(rows):
     """Trim shared left padding and trailing spaces for stable on-screen previews."""
     non_empty = [r for r in rows if r.strip()]
@@ -131,6 +155,50 @@ def _draw_font_picker(faces, selected):
         print(f"    {shown}")
 
 
+def pick_color_theme():
+    """Interactive color theme picker. Defaults to 'green' if not TTY.
+
+    Displays a menu of available themes and lets user select with arrow keys.
+    Non-interactive environments (piped stdin, CI) silently default to green.
+    """
+    # Non-interactive fallback
+    if not sys.stdin.isatty():
+        config.set_active_theme("green")
+        return
+
+    # Interactive picker
+    themes_list = list(themes.THEME_REGISTRY.items())
+    selected = 0
+
+    fd = sys.stdin.fileno()
+    old_settings = termios.tcgetattr(fd)
+    try:
+        tty.setcbreak(fd)
+        while True:
+            _draw_color_picker(themes_list, selected)
+            key = _read_picker_key()
+            if key == "up":
+                selected = max(0, selected - 1)
+            elif key == "down":
+                selected = min(len(themes_list) - 1, selected + 1)
+            elif key == "enter":
+                break
+            elif key == "interrupt":
+                raise KeyboardInterrupt
+    finally:
+        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
+
+    selected_theme_id = themes_list[selected][0]
+    config.set_active_theme(selected_theme_id)
+
+    theme_name = themes_list[selected][1].name
+    print(f"  {G_DIM}> using {theme_name}{RST}")
+    time.sleep(0.8)
+    print(CLR, end="")
+    print(CURSOR_OFF, end="")
+    print()
+
+
 def pick_font_face():
     """Interactive startup picker for selecting a face from repo OTF files."""
     if not config.FONT_PICKER:
@@ -262,6 +330,7 @@ def main():
     w = tw()
     print(CLR, end="")
     print(CURSOR_OFF, end="")
+    pick_color_theme()
     pick_font_face()
     w = tw()
     print()
@@ -274,7 +343,7 @@ def main():
     print()
     _subtitle = {
         "poetry": "literary consciousness stream",
-        "code":   "source consciousness stream",
+        "code": "source consciousness stream",
     }.get(config.MODE, "digital consciousness stream")
     print(f"  {W_DIM}v0.1 · {_subtitle}{RST}")
     print(f"  {W_GHOST}{'─' * (w - 4)}{RST}")
@@ -298,6 +367,7 @@ def main():
         save_cache(items)
     elif config.MODE == "code":
         from engine.fetch_code import fetch_code
+
         slow_print("  > INITIALIZING SOURCE ARRAY...\n")
         time.sleep(0.2)
         print()

engine/config.py

@@ -189,8 +189,10 @@ HEADLINE_LIMIT = 1000
 FEED_TIMEOUT = 10
 MIC_THRESHOLD_DB = 50  # dB above which glitches intensify
 MODE = (
-    "poetry" if "--poetry" in sys.argv or "-p" in sys.argv
+    "poetry"
-    else "code" if "--code" in sys.argv
+    if "--poetry" in sys.argv or "-p" in sys.argv
+    else "code"
+    if "--code" in sys.argv
     else "news"
 )
 FIREHOSE = "--firehose" in sys.argv
@@ -235,3 +237,26 @@ def set_font_selection(font_path=None, font_index=None):
         FONT_PATH = _resolve_font_path(font_path)
     if font_index is not None:
         FONT_INDEX = max(0, int(font_index))
+
+
+# ─── THEME MANAGEMENT ─────────────────────────────────────────
+ACTIVE_THEME = None
+
+
+def set_active_theme(theme_id: str = "green"):
+    """Set the active theme by ID.
+
+    Args:
+        theme_id: Theme identifier ("green", "orange", or "purple")
+                  Defaults to "green"
+
+    Raises:
+        KeyError: If theme_id is not in the theme registry
+
+    Side Effects:
+        Sets the ACTIVE_THEME global variable
+    """
+    global ACTIVE_THEME
+    from engine import themes
+
+    ACTIVE_THEME = themes.get_theme(theme_id)

engine/render.py

@@ -15,38 +15,72 @@ from engine.sources import NO_UPPER, SCRIPT_FONTS, SOURCE_LANGS
 from engine.terminal import RST
 from engine.translate import detect_location_language, translate_headline
 
-# ─── GRADIENT ─────────────────────────────────────────────
-# Left → right: white-hot leading edge fades to near-black
-GRAD_COLS = [
-    "\033[1;38;5;231m",  # white
-    "\033[1;38;5;195m",  # pale cyan-white
-    "\033[38;5;123m",  # bright cyan
-    "\033[38;5;118m",  # bright lime
-    "\033[38;5;82m",  # lime
-    "\033[38;5;46m",  # bright green
-    "\033[38;5;40m",  # green
-    "\033[38;5;34m",  # medium green
-    "\033[38;5;28m",  # dark green
-    "\033[38;5;22m",  # deep green
-    "\033[2;38;5;22m",  # dim deep green
-    "\033[2;38;5;235m",  # near black
-]
 
-# Complementary sweep for queue messages (opposite hue family from ticker greens)
+# ─── GRADIENT ─────────────────────────────────────────────
-MSG_GRAD_COLS = [
+def _color_codes_to_ansi(color_codes):
-    "\033[1;38;5;231m",  # white
+    """Convert a list of 256-color codes to ANSI escape code strings.
-    "\033[1;38;5;225m",  # pale pink-white
+
-    "\033[38;5;219m",  # bright pink
+    Pattern: first 2 are bold, middle 8 are normal, last 2 are dim.
-    "\033[38;5;213m",  # hot pink
+
-    "\033[38;5;207m",  # magenta
+    Args:
-    "\033[38;5;201m",  # bright magenta
+        color_codes: List of 12 integers (256-color palette codes)
-    "\033[38;5;165m",  # orchid-red
+
-    "\033[38;5;161m",  # ruby-magenta
+    Returns:
-    "\033[38;5;125m",  # dark magenta
+        List of ANSI escape code strings
-    "\033[38;5;89m",  # deep maroon-magenta
+    """
-    "\033[2;38;5;89m",  # dim deep maroon-magenta
+    if not color_codes or len(color_codes) != 12:
-    "\033[2;38;5;235m",  # near black
+        # Fallback to default green if invalid
-]
+        return _default_green_gradient()
+
+    result = []
+    for i, code in enumerate(color_codes):
+        if i < 2:
+            # Bold for first 2 (bright leading edge)
+            result.append(f"\033[1;38;5;{code}m")
+        elif i < 10:
+            # Normal for middle 8
+            result.append(f"\033[38;5;{code}m")
+        else:
+            # Dim for last 2 (dark trailing edge)
+            result.append(f"\033[2;38;5;{code}m")
+    return result
+
+
+def _default_green_gradient():
+    """Return the default 12-color green gradient for fallback when no theme is active."""
+    return [
+        "\033[1;38;5;231m",  # white
+        "\033[1;38;5;195m",  # pale cyan-white
+        "\033[38;5;123m",  # bright cyan
+        "\033[38;5;118m",  # bright lime
+        "\033[38;5;82m",  # lime
+        "\033[38;5;46m",  # bright green
+        "\033[38;5;40m",  # green
+        "\033[38;5;34m",  # medium green
+        "\033[38;5;28m",  # dark green
+        "\033[38;5;22m",  # deep green
+        "\033[2;38;5;22m",  # dim deep green
+        "\033[2;38;5;235m",  # near black
+    ]
+
+
+def _default_magenta_gradient():
+    """Return the default 12-color magenta gradient for fallback when no theme is active."""
+    return [
+        "\033[1;38;5;231m",  # white
+        "\033[1;38;5;225m",  # pale pink-white
+        "\033[38;5;219m",  # bright pink
+        "\033[38;5;213m",  # hot pink
+        "\033[38;5;207m",  # magenta
+        "\033[38;5;201m",  # bright magenta
+        "\033[38;5;165m",  # orchid-red
+        "\033[38;5;161m",  # ruby-magenta
+        "\033[38;5;125m",  # dark magenta
+        "\033[38;5;89m",  # deep maroon-magenta
+        "\033[2;38;5;89m",  # dim deep maroon-magenta
+        "\033[2;38;5;235m",  # near black
+    ]
+
 
 # ─── FONT LOADING ─────────────────────────────────────────
 _FONT_OBJ = None
@@ -189,9 +223,15 @@ def big_wrap(text, max_w, fnt=None):
     return out
 
 
-def lr_gradient(rows, offset=0.0, grad_cols=None):
+def lr_gradient(rows, offset=0.0, cols=None):
     """Color each non-space block character with a shifting left-to-right gradient."""
-    cols = grad_cols or GRAD_COLS
+    if cols is None:
+        from engine import config
+
+        if config.ACTIVE_THEME:
+            cols = _color_codes_to_ansi(config.ACTIVE_THEME.main_gradient)
+        else:
+            cols = _default_green_gradient()
     n = len(cols)
     max_x = max((len(r.rstrip()) for r in rows if r.strip()), default=1)
     out = []
@@ -213,7 +253,30 @@ def lr_gradient(rows, offset=0.0, grad_cols=None):
 
 def lr_gradient_opposite(rows, offset=0.0):
     """Complementary (opposite wheel) gradient used for queue message panels."""
-    return lr_gradient(rows, offset, MSG_GRAD_COLS)
+    return lr_gradient(rows, offset, _default_magenta_gradient())
+
+
+def msg_gradient(rows, offset):
+    """Apply message (ntfy) gradient using theme complementary colors.
+
+    Returns colored rows using ACTIVE_THEME.message_gradient if available,
+    falling back to default magenta if no theme is set.
+
+    Args:
+        rows: List of text strings to colorize
+        offset: Gradient offset (0.0-1.0) for animation
+
+    Returns:
+        List of rows with ANSI color codes applied
+    """
+    from engine import config
+
+    cols = (
+        _color_codes_to_ansi(config.ACTIVE_THEME.message_gradient)
+        if config.ACTIVE_THEME
+        else _default_magenta_gradient()
+    )
+    return lr_gradient(rows, offset, cols)
 
 
 # ─── HEADLINE BLOCK ASSEMBLY ─────────────────────────────

engine/themes.py

@@ -0,0 +1,60 @@
+"""
+Theme definitions with color gradients for terminal rendering.
+
+This module is data-only and does not import config or render
+to prevent circular dependencies.
+"""
+
+
+class Theme:
+    """Represents a color theme with two gradients."""
+
+    def __init__(self, name, main_gradient, message_gradient):
+        """Initialize a theme with name and color gradients.
+
+        Args:
+            name: Theme identifier string
+            main_gradient: List of 12 ANSI 256-color codes for main gradient
+            message_gradient: List of 12 ANSI 256-color codes for message gradient
+        """
+        self.name = name
+        self.main_gradient = main_gradient
+        self.message_gradient = message_gradient
+
+
+# ─── GRADIENT DEFINITIONS ─────────────────────────────────────────────────
+# Each gradient is 12 ANSI 256-color codes in sequence
+# Format: [light...] → [medium...] → [dark...] → [black]
+
+_GREEN_MAIN = [231, 195, 123, 118, 82, 46, 40, 34, 28, 22, 22, 235]
+_GREEN_MSG = [231, 225, 219, 213, 207, 201, 165, 161, 125, 89, 89, 235]
+
+_ORANGE_MAIN = [231, 215, 209, 208, 202, 166, 130, 94, 58, 94, 94, 235]
+_ORANGE_MSG = [231, 195, 33, 27, 21, 21, 21, 18, 18, 18, 18, 235]
+
+_PURPLE_MAIN = [231, 225, 177, 171, 165, 135, 129, 93, 57, 57, 57, 235]
+_PURPLE_MSG = [231, 226, 226, 220, 220, 184, 184, 178, 178, 172, 172, 235]
+
+
+# ─── THEME REGISTRY ───────────────────────────────────────────────────────
+
+THEME_REGISTRY = {
+    "green": Theme("green", _GREEN_MAIN, _GREEN_MSG),
+    "orange": Theme("orange", _ORANGE_MAIN, _ORANGE_MSG),
+    "purple": Theme("purple", _PURPLE_MAIN, _PURPLE_MSG),
+}
+
+
+def get_theme(theme_id):
+    """Retrieve a theme by ID.
+
+    Args:
+        theme_id: Theme identifier string
+
+    Returns:
+        Theme object matching the ID
+
+    Raises:
+        KeyError: If theme_id is not in registry
+    """
+    return THEME_REGISTRY[theme_id]

tests/test_render.py

@@ -0,0 +1,301 @@
+"""
+Tests for engine.render module.
+"""
+
+import pytest
+
+from engine import config, render
+
+
+class TestDefaultGradients:
+    """Tests for default gradient fallback functions."""
+
+    def test_default_green_gradient_length(self):
+        """_default_green_gradient returns 12 colors."""
+        gradient = render._default_green_gradient()
+        assert len(gradient) == 12
+
+    def test_default_green_gradient_is_list(self):
+        """_default_green_gradient returns a list."""
+        gradient = render._default_green_gradient()
+        assert isinstance(gradient, list)
+
+    def test_default_green_gradient_all_strings(self):
+        """_default_green_gradient returns list of ANSI code strings."""
+        gradient = render._default_green_gradient()
+        assert all(isinstance(code, str) for code in gradient)
+
+    def test_default_magenta_gradient_length(self):
+        """_default_magenta_gradient returns 12 colors."""
+        gradient = render._default_magenta_gradient()
+        assert len(gradient) == 12
+
+    def test_default_magenta_gradient_is_list(self):
+        """_default_magenta_gradient returns a list."""
+        gradient = render._default_magenta_gradient()
+        assert isinstance(gradient, list)
+
+    def test_default_magenta_gradient_all_strings(self):
+        """_default_magenta_gradient returns list of ANSI code strings."""
+        gradient = render._default_magenta_gradient()
+        assert all(isinstance(code, str) for code in gradient)
+
+
+class TestLrGradientUsesActiveTheme:
+    """Tests for lr_gradient using active theme."""
+
+    def test_lr_gradient_uses_active_theme_when_cols_none(self):
+        """lr_gradient uses ACTIVE_THEME.main_gradient when cols=None."""
+        # Save original state
+        original_theme = config.ACTIVE_THEME
+
+        try:
+            # Set a theme
+            config.set_active_theme("green")
+
+            # Create simple test data
+            rows = ["text"]
+
+            # Call without cols parameter (cols=None)
+            result = render.lr_gradient(rows, offset=0.0)
+
+            # Should not raise and should return colored output
+            assert isinstance(result, list)
+            assert len(result) == 1
+            # Should have ANSI codes (no plain "text")
+            assert result[0] != "text"
+        finally:
+            # Restore original state
+            config.ACTIVE_THEME = original_theme
+
+    def test_lr_gradient_fallback_when_no_theme(self):
+        """lr_gradient uses fallback green when ACTIVE_THEME is None."""
+        # Save original state
+        original_theme = config.ACTIVE_THEME
+
+        try:
+            # Clear the theme
+            config.ACTIVE_THEME = None
+
+            # Create simple test data
+            rows = ["text"]
+
+            # Call without cols parameter (should use fallback)
+            result = render.lr_gradient(rows, offset=0.0)
+
+            # Should not raise and should return colored output
+            assert isinstance(result, list)
+            assert len(result) == 1
+            # Should have ANSI codes (no plain "text")
+            assert result[0] != "text"
+        finally:
+            # Restore original state
+            config.ACTIVE_THEME = original_theme
+
+    def test_lr_gradient_explicit_cols_parameter_still_works(self):
+        """lr_gradient with explicit cols parameter overrides theme."""
+        # Custom gradient
+        custom_cols = ["\033[38;5;1m", "\033[38;5;2m"] * 6
+
+        rows = ["xy"]
+        result = render.lr_gradient(rows, offset=0.0, cols=custom_cols)
+
+        # Should use the provided cols
+        assert isinstance(result, list)
+        assert len(result) == 1
+
+    def test_lr_gradient_respects_cols_parameter_name(self):
+        """lr_gradient accepts cols as keyword argument."""
+        custom_cols = ["\033[38;5;1m", "\033[38;5;2m"] * 6
+
+        rows = ["xy"]
+        # Call with cols as keyword
+        result = render.lr_gradient(rows, offset=0.0, cols=custom_cols)
+
+        assert isinstance(result, list)
+
+
+class TestLrGradientBasicFunctionality:
+    """Tests to ensure lr_gradient basic functionality still works."""
+
+    def test_lr_gradient_colors_non_space_chars(self):
+        """lr_gradient colors non-space characters."""
+        rows = ["hello"]
+
+        # Set a theme for the test
+        original_theme = config.ACTIVE_THEME
+        try:
+            config.set_active_theme("green")
+            result = render.lr_gradient(rows, offset=0.0)
+
+            # Result should have ANSI codes
+            assert any("\033[" in r for r in result), "Expected ANSI codes in result"
+        finally:
+            config.ACTIVE_THEME = original_theme
+
+    def test_lr_gradient_preserves_spaces(self):
+        """lr_gradient preserves spaces in output."""
+        rows = ["a b c"]
+
+        original_theme = config.ACTIVE_THEME
+        try:
+            config.set_active_theme("green")
+            result = render.lr_gradient(rows, offset=0.0)
+
+            # Spaces should be preserved (not colored)
+            assert " " in result[0]
+        finally:
+            config.ACTIVE_THEME = original_theme
+
+    def test_lr_gradient_empty_rows(self):
+        """lr_gradient handles empty rows correctly."""
+        rows = [""]
+
+        original_theme = config.ACTIVE_THEME
+        try:
+            config.set_active_theme("green")
+            result = render.lr_gradient(rows, offset=0.0)
+
+            assert result == [""]
+        finally:
+            config.ACTIVE_THEME = original_theme
+
+    def test_lr_gradient_multiple_rows(self):
+        """lr_gradient handles multiple rows."""
+        rows = ["row1", "row2", "row3"]
+
+        original_theme = config.ACTIVE_THEME
+        try:
+            config.set_active_theme("green")
+            result = render.lr_gradient(rows, offset=0.0)
+
+            assert len(result) == 3
+        finally:
+            config.ACTIVE_THEME = original_theme
+
+
+class TestMsgGradient:
+    """Tests for msg_gradient function (message/ntfy overlay coloring)."""
+
+    def test_msg_gradient_uses_active_theme(self):
+        """msg_gradient uses ACTIVE_THEME.message_gradient when theme is set."""
+        # Save original state
+        original_theme = config.ACTIVE_THEME
+
+        try:
+            # Set a theme
+            config.set_active_theme("green")
+
+            # Create simple test data
+            rows = ["MESSAGE"]
+
+            # Call msg_gradient
+            result = render.msg_gradient(rows, offset=0.0)
+
+            # Should return colored output using theme's message_gradient
+            assert isinstance(result, list)
+            assert len(result) == 1
+            # Should have ANSI codes from the message gradient
+            assert result[0] != "MESSAGE"
+            assert "\033[" in result[0]
+        finally:
+            # Restore original state
+            config.ACTIVE_THEME = original_theme
+
+    def test_msg_gradient_fallback_when_no_theme(self):
+        """msg_gradient uses fallback magenta when ACTIVE_THEME is None."""
+        # Save original state
+        original_theme = config.ACTIVE_THEME
+
+        try:
+            # Clear the theme
+            config.ACTIVE_THEME = None
+
+            # Create simple test data
+            rows = ["MESSAGE"]
+
+            # Call msg_gradient
+            result = render.msg_gradient(rows, offset=0.0)
+
+            # Should return colored output using default magenta
+            assert isinstance(result, list)
+            assert len(result) == 1
+            # Should have ANSI codes
+            assert result[0] != "MESSAGE"
+            assert "\033[" in result[0]
+        finally:
+            # Restore original state
+            config.ACTIVE_THEME = original_theme
+
+    def test_msg_gradient_returns_colored_rows(self):
+        """msg_gradient returns properly colored rows with animation offset."""
+        # Save original state
+        original_theme = config.ACTIVE_THEME
+
+        try:
+            # Set a theme
+            config.set_active_theme("orange")
+
+            rows = ["NTFY", "ALERT"]
+
+            # Call with offset
+            result = render.msg_gradient(rows, offset=0.5)
+
+            # Should return same number of rows
+            assert len(result) == 2
+            # Both should be colored
+            assert all("\033[" in r for r in result)
+            # Should not be the original text
+            assert result != rows
+        finally:
+            config.ACTIVE_THEME = original_theme
+
+    def test_msg_gradient_different_themes_produce_different_results(self):
+        """msg_gradient produces different colors for different themes."""
+        original_theme = config.ACTIVE_THEME
+
+        try:
+            rows = ["TEST"]
+
+            # Get result with green theme
+            config.set_active_theme("green")
+            result_green = render.msg_gradient(rows, offset=0.0)
+
+            # Get result with orange theme
+            config.set_active_theme("orange")
+            result_orange = render.msg_gradient(rows, offset=0.0)
+
+            # Results should be different (different message gradients)
+            assert result_green != result_orange
+        finally:
+            config.ACTIVE_THEME = original_theme
+
+    def test_msg_gradient_preserves_spacing(self):
+        """msg_gradient preserves spaces in rows."""
+        original_theme = config.ACTIVE_THEME
+
+        try:
+            config.set_active_theme("purple")
+            rows = ["M E S S A G E"]
+
+            result = render.msg_gradient(rows, offset=0.0)
+
+            # Spaces should be preserved
+            assert " " in result[0]
+        finally:
+            config.ACTIVE_THEME = original_theme
+
+    def test_msg_gradient_empty_rows(self):
+        """msg_gradient handles empty rows correctly."""
+        original_theme = config.ACTIVE_THEME
+
+        try:
+            config.set_active_theme("green")
+            rows = [""]
+
+            result = render.msg_gradient(rows, offset=0.0)
+
+            # Empty row should stay empty
+            assert result == [""]
+        finally:
+            config.ACTIVE_THEME = original_theme

tests/test_themes.py

@@ -0,0 +1,169 @@
+"""
+Tests for engine.themes module.
+"""
+
+import pytest
+
+from engine import themes
+
+
+class TestThemeConstruction:
+    """Tests for Theme class initialization."""
+
+    def test_theme_construction(self):
+        """Theme stores name and gradients correctly."""
+        main_grad = ["color1", "color2", "color3"]
+        msg_grad = ["msg1", "msg2", "msg3"]
+        theme = themes.Theme("test_theme", main_grad, msg_grad)
+
+        assert theme.name == "test_theme"
+        assert theme.main_gradient == main_grad
+        assert theme.message_gradient == msg_grad
+
+
+class TestGradientLength:
+    """Tests for gradient length validation."""
+
+    def test_gradient_length_green(self):
+        """Green theme has exactly 12 colors in each gradient."""
+        green = themes.THEME_REGISTRY["green"]
+        assert len(green.main_gradient) == 12
+        assert len(green.message_gradient) == 12
+
+    def test_gradient_length_orange(self):
+        """Orange theme has exactly 12 colors in each gradient."""
+        orange = themes.THEME_REGISTRY["orange"]
+        assert len(orange.main_gradient) == 12
+        assert len(orange.message_gradient) == 12
+
+    def test_gradient_length_purple(self):
+        """Purple theme has exactly 12 colors in each gradient."""
+        purple = themes.THEME_REGISTRY["purple"]
+        assert len(purple.main_gradient) == 12
+        assert len(purple.message_gradient) == 12
+
+
+class TestThemeRegistry:
+    """Tests for THEME_REGISTRY dictionary."""
+
+    def test_theme_registry_has_three_themes(self):
+        """Registry contains exactly three themes: green, orange, purple."""
+        assert len(themes.THEME_REGISTRY) == 3
+        assert set(themes.THEME_REGISTRY.keys()) == {"green", "orange", "purple"}
+
+    def test_registry_values_are_themes(self):
+        """All registry values are Theme instances."""
+        for theme_id, theme in themes.THEME_REGISTRY.items():
+            assert isinstance(theme, themes.Theme)
+            assert theme.name == theme_id
+
+
+class TestGetTheme:
+    """Tests for get_theme function."""
+
+    def test_get_theme_valid_green(self):
+        """get_theme('green') returns correct green Theme."""
+        green = themes.get_theme("green")
+        assert isinstance(green, themes.Theme)
+        assert green.name == "green"
+
+    def test_get_theme_valid_orange(self):
+        """get_theme('orange') returns correct orange Theme."""
+        orange = themes.get_theme("orange")
+        assert isinstance(orange, themes.Theme)
+        assert orange.name == "orange"
+
+    def test_get_theme_valid_purple(self):
+        """get_theme('purple') returns correct purple Theme."""
+        purple = themes.get_theme("purple")
+        assert isinstance(purple, themes.Theme)
+        assert purple.name == "purple"
+
+    def test_get_theme_invalid(self):
+        """get_theme with invalid ID raises KeyError."""
+        with pytest.raises(KeyError):
+            themes.get_theme("invalid_theme")
+
+    def test_get_theme_invalid_none(self):
+        """get_theme with None raises KeyError."""
+        with pytest.raises(KeyError):
+            themes.get_theme(None)
+
+
+class TestGreenTheme:
+    """Tests for green theme specific values."""
+
+    def test_green_theme_unchanged(self):
+        """Green theme maintains original color sequence."""
+        green = themes.get_theme("green")
+
+        # Expected main gradient: 231→195→123→118→82→46→40→34→28→22→22(dim)→235
+        expected_main = [231, 195, 123, 118, 82, 46, 40, 34, 28, 22, 22, 235]
+        # Expected msg gradient: 231→225→219→213→207→201→165→161→125→89→89(dim)→235
+        expected_msg = [231, 225, 219, 213, 207, 201, 165, 161, 125, 89, 89, 235]
+
+        assert green.main_gradient == expected_main
+        assert green.message_gradient == expected_msg
+
+    def test_green_theme_name(self):
+        """Green theme has correct name."""
+        green = themes.get_theme("green")
+        assert green.name == "green"
+
+
+class TestOrangeTheme:
+    """Tests for orange theme specific values."""
+
+    def test_orange_theme_unchanged(self):
+        """Orange theme maintains original color sequence."""
+        orange = themes.get_theme("orange")
+
+        # Expected main gradient: 231→215→209→208→202→166→130→94→58→94→94(dim)→235
+        expected_main = [231, 215, 209, 208, 202, 166, 130, 94, 58, 94, 94, 235]
+        # Expected msg gradient: 231→195→33→27→21→21→21→18→18→18→18(dim)→235
+        expected_msg = [231, 195, 33, 27, 21, 21, 21, 18, 18, 18, 18, 235]
+
+        assert orange.main_gradient == expected_main
+        assert orange.message_gradient == expected_msg
+
+    def test_orange_theme_name(self):
+        """Orange theme has correct name."""
+        orange = themes.get_theme("orange")
+        assert orange.name == "orange"
+
+
+class TestPurpleTheme:
+    """Tests for purple theme specific values."""
+
+    def test_purple_theme_unchanged(self):
+        """Purple theme maintains original color sequence."""
+        purple = themes.get_theme("purple")
+
+        # Expected main gradient: 231→225→177→171→165→135→129→93→57→57→57(dim)→235
+        expected_main = [231, 225, 177, 171, 165, 135, 129, 93, 57, 57, 57, 235]
+        # Expected msg gradient: 231→226→226→220→220→184→184→178→178→172→172(dim)→235
+        expected_msg = [231, 226, 226, 220, 220, 184, 184, 178, 178, 172, 172, 235]
+
+        assert purple.main_gradient == expected_main
+        assert purple.message_gradient == expected_msg
+
+    def test_purple_theme_name(self):
+        """Purple theme has correct name."""
+        purple = themes.get_theme("purple")
+        assert purple.name == "purple"
+
+
+class TestThemeDataOnly:
+    """Tests to ensure themes module has no problematic imports."""
+
+    def test_themes_module_imports(self):
+        """themes module should be data-only without config/render imports."""
+        import inspect
+        source = inspect.getsource(themes)
+        # Verify no imports of config or render (look for actual import statements)
+        lines = source.split('\n')
+        import_lines = [line for line in lines if line.strip().startswith('import ') or line.strip().startswith('from ')]
+        # Filter out empty and comment lines
+        import_lines = [line for line in import_lines if line.strip() and not line.strip().startswith('#')]
+        # Should have no import lines
+        assert len(import_lines) == 0, f"Found unexpected imports: {import_lines}"