feat(daemon): add display abstraction and daemon mode with C&C

engine/display.py

@@ -0,0 +1,102 @@
+"""
+Display output abstraction - allows swapping output backends.
+
+Protocol:
+    - init(width, height): Initialize display with terminal dimensions
+    - show(buffer): Render buffer (list of strings) to display
+    - clear(): Clear the display
+    - cleanup(): Shutdown display
+"""
+
+import time
+from typing import Protocol
+
+
+class Display(Protocol):
+    """Protocol for display backends."""
+
+    def init(self, width: int, height: int) -> None:
+        """Initialize display with dimensions."""
+        ...
+
+    def show(self, buffer: list[str]) -> None:
+        """Show buffer on display."""
+        ...
+
+    def clear(self) -> None:
+        """Clear display."""
+        ...
+
+    def cleanup(self) -> None:
+        """Shutdown display."""
+        ...
+
+
+def get_monitor():
+    """Get the performance monitor."""
+    try:
+        from engine.effects.performance import get_monitor as _get_monitor
+
+        return _get_monitor()
+    except Exception:
+        return None
+
+
+class TerminalDisplay:
+    """ANSI terminal display backend."""
+
+    def __init__(self):
+        self.width = 80
+        self.height = 24
+
+    def init(self, width: int, height: int) -> None:
+        from engine.terminal import CURSOR_OFF
+
+        self.width = width
+        self.height = height
+        print(CURSOR_OFF, end="", flush=True)
+
+    def show(self, buffer: list[str]) -> None:
+        import sys
+
+        t0 = time.perf_counter()
+        sys.stdout.buffer.write("".join(buffer).encode())
+        sys.stdout.flush()
+        elapsed_ms = (time.perf_counter() - t0) * 1000
+
+        monitor = get_monitor()
+        if monitor:
+            chars_in = sum(len(line) for line in buffer)
+            monitor.record_effect("terminal_display", elapsed_ms, chars_in, chars_in)
+
+    def clear(self) -> None:
+        from engine.terminal import CLR
+
+        print(CLR, end="", flush=True)
+
+    def cleanup(self) -> None:
+        from engine.terminal import CURSOR_ON
+
+        print(CURSOR_ON, end="", flush=True)
+
+
+class NullDisplay:
+    """Headless/null display - discards all output."""
+
+    def init(self, width: int, height: int) -> None:
+        self.width = width
+        self.height = height
+
+    def show(self, buffer: list[str]) -> None:
+        monitor = get_monitor()
+        if monitor:
+            t0 = time.perf_counter()
+            chars_in = sum(len(line) for line in buffer)
+            elapsed_ms = (time.perf_counter() - t0) * 1000
+            monitor.record_effect("null_display", elapsed_ms, chars_in, chars_in)
+
+    def clear(self) -> None:
+        pass
+
+    def cleanup(self) -> None:
+        pass

engine/scroll.py

@@ -4,33 +4,42 @@ Orchestrates viewport, frame timing, and layers.
 """
 
 import random
-import sys
 import time
 
 from engine import config
+from engine.display import (
+    Display,
+    TerminalDisplay,
+)
+from engine.display import (
+    get_monitor as _get_display_monitor,
+)
 from engine.frame import calculate_scroll_step
 from engine.layers import (
     apply_glitch,
+    process_effects,
     render_firehose,
     render_message_overlay,
     render_ticker_zone,
 )
-from engine.terminal import CLR
 from engine.viewport import th, tw
 
+USE_EFFECT_CHAIN = True
 
-def stream(items, ntfy_poller, mic_monitor):
+
+def stream(items, ntfy_poller, mic_monitor, display: Display | None = None):
     """Main render loop with four layers: message, ticker, scroll motion, firehose."""
+    if display is None:
+        display = TerminalDisplay()
     random.shuffle(items)
     pool = list(items)
     seen = set()
     queued = 0
 
     time.sleep(0.5)
-    sys.stdout.write(CLR)
-    sys.stdout.flush()
-
     w, h = tw(), th()
+    display.init(w, h)
+    display.clear()
     fh = config.FIREHOSE_H if config.FIREHOSE else 0
     ticker_view_h = h - fh
     GAP = 3
@@ -42,6 +51,7 @@ def stream(items, ntfy_poller, mic_monitor):
     noise_cache = {}
     scroll_motion_accum = 0.0
     msg_cache = (None, None)
+    frame_number = 0
 
     while True:
         if queued >= config.HEADLINE_LIMIT and not active:
@@ -93,19 +103,39 @@ def stream(items, ntfy_poller, mic_monitor):
         buf.extend(ticker_buf)
 
         mic_excess = mic_monitor.excess
-        buf = apply_glitch(buf, ticker_buf_start, mic_excess, w)
+        render_start = time.perf_counter()
 
-        firehose_buf = render_firehose(items, w, fh, h)
-        buf.extend(firehose_buf)
+        if USE_EFFECT_CHAIN:
+            buf = process_effects(
+                buf,
+                w,
+                h,
+                scroll_cam,
+                ticker_h,
+                mic_excess,
+                grad_offset,
+                frame_number,
+                msg is not None,
+                items,
+            )
+        else:
+            buf = apply_glitch(buf, ticker_buf_start, mic_excess, w)
+            firehose_buf = render_firehose(items, w, fh, h)
+            buf.extend(firehose_buf)
 
         if msg_overlay:
             buf.extend(msg_overlay)
 
-        sys.stdout.buffer.write("".join(buf).encode())
-        sys.stdout.flush()
+        render_elapsed = (time.perf_counter() - render_start) * 1000
+        monitor = _get_display_monitor()
+        if monitor:
+            chars = sum(len(line) for line in buf)
+            monitor.record_effect("render", render_elapsed, chars, chars)
+
+        display.show(buf)
 
         elapsed = time.monotonic() - t0
         time.sleep(max(0, config.FRAME_DT - elapsed))
+        frame_number += 1
 
-    sys.stdout.write(CLR)
-    sys.stdout.flush()
+    display.cleanup()