#!/usr/bin/env python3
"""Convert declarative flow YAML to Node-RED flow JSON."""
import json
import sys
import uuid
import yaml

COLUMNS = [170, 450, 770]
ROW_HEIGHT = 140
BROKER_DEFAULTS = {
    "clientid": "", "autoConnect": True, "usetls": False,
    "protocolVersion": "4", "keepalive": "60", "cleansession": True,
    "birthTopic": "", "birthQos": "0", "birthPayload": "",
    "closeTopic": "", "closeQos": "0", "closePayload": "",
    "willTopic": "", "willQos": "0", "willPayload": "",
}

NODE_TEMPLATES = {
    "mqtt-in": {
        "nl": False, "rap": True, "rh": 0, "inputs": 0, "datatype": "auto",
    },
    "mqtt-out": {
        "qos": "2", "retain": False, "respTopic": "", "contentType": "",
        "userProps": "", "correl": "", "expiry": "",
    },
    "debug": {
        "active": True, "tosidebar": True, "console": False,
        "tostatus": False, "complete": "payload", "targetType": "msg",
        "statusVal": "", "statusType": "auto",
    },
    "ui-text": {
        "width": "6", "height": "2", "layout": "row-spread",
    },
    "ui-button": {
        "width": "3", "height": "1", "payloadType": "json",
    },
}


def new_id(prefix="n"):
    return prefix + uuid.uuid4().hex[:8]


def make_broker_node(name, cfg, flow_id):
    node = {"id": new_id("br"), "z": "", "type": "mqtt-broker", "name": name}
    node["broker"] = cfg["host"]
    node["port"] = str(cfg.get("port", 1883))
    for k, v in BROKER_DEFAULTS.items():
        node.setdefault(k, v)
    return node


def make_node(nd, col, row, broker_map, group_map, flow_id):
    ntype = nd["type"]
    nid = nd["id"] if "id" in nd else new_id()
    node = {"id": nid, "z": flow_id, "type": ntype, "name": nd.get("label", nd.get("name", ""))}
    node.update(NODE_TEMPLATES.get(ntype, {}))
    node["x"] = COLUMNS[col] if col < len(COLUMNS) else col * 300 + 170
    node["y"] = row * ROW_HEIGHT + 80

    if ntype in ("mqtt-in", "mqtt-out"):
        node["broker"] = broker_map[nd["broker"]]
    if ntype in ("ui-text", "ui-button"):
        node["group"] = group_map[nd["group"]]
    if ntype == "mqtt-in":
        node["topic"] = nd["topic"]
        node["qos"] = str(nd.get("qos", 2))
    if ntype == "mqtt-out":
        node["topic"] = nd.get("topic", "")
        node["qos"] = str(nd.get("qos", 2))
    if ntype == "ui-text":
        node["format"] = nd.get("format", "{{msg.payload}}")
        node["name"] = nd.get("label", nd.get("name", "Text"))
    if ntype == "ui-button":
        node["payload"] = json.dumps(nd.get("payload", ""))
        node["topic"] = nd.get("topic", "")
        node["name"] = nd.get("label", nd.get("name", "Button"))
    if ntype == "debug":
        node["name"] = nd.get("label", nd.get("name", "Debug"))

    return node


def make_group_node(name, tab_id, order):
    return {
        "id": new_id("g"), "z": tab_id, "type": "ui_group",
        "name": name, "tab": tab_id, "order": order,
        "disp": True, "width": "6",
    }


def make_tab_node(name, icon, order):
    tab_id = new_id("t")
    return tab_id, {
        "id": tab_id, "z": "", "type": "ui_tab",
        "name": name, "icon": icon, "order": order,
        "disabled": False, "hidden": False,
    }


def build_flow(doc, flow_def, node_positions):
    nodes = []
    flow_id = new_id("f")

    # Collect broker references
    broker_map = {}
    for nd in flow_def["nodes"]:
        if nd["type"] in ("mqtt-in", "mqtt-out") and "broker" in nd:
            bname = nd["broker"]
            if bname not in broker_map:
                bcfg = doc["brokers"][bname]
                bn = make_broker_node(bname, bcfg, flow_id)
                broker_map[bname] = bn["id"]
                nodes.append(bn)

    # Collect dashboard groups/tabs
    group_map = {}
    if "dashboards" in doc:
        for db in doc["dashboards"]:
            tab_id, tn = make_tab_node(db["tab"], db.get("icon", "dashboard"), db.get("order", 1))
            nodes.append(tn)
            for gi, grp in enumerate(db.get("groups", [])):
                gn = make_group_node(grp["name"], tab_id, gi + 1)
                group_map[grp["name"]] = gn["id"]
                nodes.append(gn)

    # Create flow nodes with auto-positioning
    for i, nd in enumerate(flow_def["nodes"]):
        col, row = node_positions.get(nd["id"], (0, i))
        node = make_node(nd, col, row, broker_map, group_map, flow_id)
        nodes.append(node)

    # Wire connections
    wires = flow_def.get("wires", {})
    for src_id, targets in wires.items():
        src = next(n for n in nodes if n.get("id") == src_id or n.get("name", "").lower().replace(" ", "-") == src_id)
        src.setdefault("wires", [])
        src["wires"].append(targets)

    return nodes


def auto_position(flow_def):
    """Simple auto-layout: put each node in a column determined by its role."""
    positions = {}
    col_order = {"mqtt-in": 0, "ui-button": 0, "inject": 0,
                 "debug": 2, "ui-text": 2, "mqtt-out": 2, "ui-chart": 2, "ui-gauge": 2}
    for i, nd in enumerate(flow_def["nodes"]):
        col = col_order.get(nd["type"], 1)
        positions[nd["id"]] = (col, i // 3)
    return positions


def main():
    doc = yaml.safe_load(open(sys.argv[1]))
    all_nodes = []
    for flow_def in doc.get("flows", []):
        positions = auto_position(flow_def)
        all_nodes += build_flow(doc, flow_def, positions)
    json.dump(all_nodes, sys.stdout, indent=2)


if __name__ == "__main__":
    main()