#!/usr/bin/env python3
"""
Sync intelligence-router model list into Hermes custom_providers.

Usage:
    # One-shot: discover models from the router and update Hermes config
    python3 scripts/sync_models.py

    # Cron mode (auto): set up via:
    #   cp scripts/sync_models.py ~/.hermes/scripts/
    #   hermes cron create --schedule "every 30m" --no-agent --script sync_models.py

Silent exit when nothing changed. Prints a summary + restarts the gateway when
the model list differs.
"""

import json
import os
import subprocess
import sys
import urllib.error
import urllib.request
from pathlib import Path

# ── CONFIGURE THESE ──────────────────────────────────────────────────
ROUTER_BASE_URL = "http://10.0.4.100:9001/v1"
PROVIDER_NAME = "intelligence_router"
GATEWAY_SERVICE = "hermes-gateway"
# ─────────────────────────────────────────────────────────────────────

MODELS_URL = f"{ROUTER_BASE_URL}/models"
CONFIG_PATH = Path(os.path.expanduser("~/.hermes/config.yaml"))


def fetch_models() -> list[str] | None:
    try:
        req = urllib.request.Request(MODELS_URL, headers={"Accept": "application/json"})
        with urllib.request.urlopen(req, timeout=10) as resp:
            data = json.loads(resp.read().decode())
        models = sorted(m["id"] for m in data.get("data", []) if isinstance(m, dict))
        return models if models else None
    except (urllib.error.URLError, TimeoutError, json.JSONDecodeError, OSError) as e:
        print(f"ERROR: Failed to fetch models from {MODELS_URL}: {e}", file=sys.stderr)
        return None


def read_current_models() -> list[str]:
    """Parse current custom_providers entries for our provider name."""
    if not CONFIG_PATH.exists():
        return []

    models = []
    with open(CONFIG_PATH) as f:
        content = f.read()

    idx = content.find("custom_providers:")
    if idx == -1:
        return []

    section = content[idx:]
    lines = section.split("\n")

    current_entry = {}
    for line in lines:
        s = line.strip()
        if s.startswith("- base_url:"):
            if current_entry.get("name") == PROVIDER_NAME:
                m = current_entry.get("model", "")
                if m:
                    models.append(m)
            current_entry = {}
        elif s.startswith("model:"):
            current_entry["model"] = s.split("model:", 1)[1].strip().strip("'\"")
        elif s.startswith("name:"):
            current_entry["name"] = s.split("name:", 1)[1].strip().strip("'\"")
        elif s and not s.startswith(("-", " ")):
            break

    # Don't forget the last entry
    if current_entry.get("name") == PROVIDER_NAME:
        m = current_entry.get("model", "")
        if m:
            models.append(m)

    return sorted(models)


def generate_block(models: list[str]) -> str:
    lines = ["custom_providers:"]
    for m in models:
        lines.append(f"- base_url: {ROUTER_BASE_URL}")
        lines.append(f"  model: {m}")
        lines.append(f"  name: {PROVIDER_NAME}")
    return "\n".join(lines)


def replace_section(models: list[str]) -> bool:
    """Replace the custom_providers section in-place. Returns True if changed."""
    if not CONFIG_PATH.exists():
        return False

    import yaml

    content = CONFIG_PATH.read_text()
    config = yaml.safe_load(content)

    new_entries = [
        {"base_url": ROUTER_BASE_URL, "model": m, "name": PROVIDER_NAME}
        for m in models
    ]

    if config.get("custom_providers") == new_entries:
        return False

    config["custom_providers"] = new_entries
    CONFIG_PATH.write_text(yaml.dump(config, default_flow_style=False, sort_keys=False))
    return True


def restart_gateway() -> bool:
    try:
        r = subprocess.run(
            ["systemctl", "--user", "restart", GATEWAY_SERVICE],
            capture_output=True, text=True, timeout=30,
        )
        return r.returncode == 0
    except Exception:
        return False


def main():
    models = fetch_models()
    if models is None:
        sys.exit(1)

    current = read_current_models()
    if current == models:
        print("Model list unchanged — nothing to do.")
        return

    added = set(models) - set(current)
    removed = set(current) - set(models)
    print(f"Model list changed! {len(current)} → {len(models)} models")
    if added:
        print(f"  Added:   {sorted(added)}")
    if removed:
        print(f"  Removed: {sorted(removed)}")

    if not replace_section(models):
        print("ERROR: Config update failed")
        return

    print("Config updated. Restarting gateway...")
    if restart_gateway():
        print("Gateway restarted successfully.")
    else:
        print("WARNING: Gateway restart failed — restart manually.")


if __name__ == "__main__":
    main()