#!/usr/bin/env python3
"""
custodian — CLI for the Custodian State Hub.

Usage:
  custodian register-project [--domain DOMAIN] [--path PATH]

  Run from inside the project directory you want to connect.
  --domain defaults to auto-detection from the project charter.
  --path defaults to current working directory.
"""
from __future__ import annotations

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

STATE_HUB_DIR = Path(__file__).resolve().parent
API_BASE = os.environ.get("API_BASE", "http://127.0.0.1:8000")
TEMPLATE = STATE_HUB_DIR / "scripts" / "project_claude_md.template"
PATCH_CWD = STATE_HUB_DIR / "scripts" / "patch_mcp_cwd.py"

# ── Helpers ────────────────────────────────────────────────────────────────────

def _api_get(path: str) -> object:
    url = API_BASE.rstrip("/") + path
    try:
        with urllib.request.urlopen(url, timeout=10) as r:
            return json.loads(r.read())
    except urllib.error.URLError as e:
        print(f"ERROR: Cannot reach API at {API_BASE}: {e}")
        print(f"  Start it: cd {STATE_HUB_DIR} && make api")
        sys.exit(1)


def _api_post(path: str, body: dict) -> object:
    url = API_BASE.rstrip("/") + path
    data = json.dumps({k: v for k, v in body.items() if v is not None}).encode()
    req = urllib.request.Request(url, data=data, headers={"Content-Type": "application/json"})
    with urllib.request.urlopen(req, timeout=10) as r:
        return json.loads(r.read())


def _detect_domain(project_path: Path) -> str | None:
    """Try to read domain from project charter frontmatter."""
    for charter in project_path.rglob("project_charter_v*.md"):
        text = charter.read_text()
        m = re.search(r"^domain:\s*(\S+)", text, re.MULTILINE)
        if m:
            return m.group(1).strip('"\'')
    return None


def _check_mcp() -> bool:
    claude_json = Path.home() / ".claude.json"
    if not claude_json.exists():
        return False
    config = json.loads(claude_json.read_text())
    return "state-hub" in config.get("mcpServers", {})


# ── Subcommands ────────────────────────────────────────────────────────────────

def cmd_register(args: argparse.Namespace) -> None:
    project_path = Path(args.path).resolve()
    if not project_path.is_dir():
        print(f"ERROR: {project_path} is not a directory.")
        sys.exit(1)

    project_name = project_path.name

    # ── Step 1: API health ─────────────────────────────────────────────────────
    print(f"==> Checking API at {API_BASE} ...")
    _api_get("/state/health")
    print("    API OK")

    # ── Step 2: Domain ─────────────────────────────────────────────────────────
    domain = args.domain
    valid_domains = [d["slug"] for d in _api_get("/domains/?status=active")]
    if not domain:
        print("==> Auto-detecting domain from project charter ...")
        domain = _detect_domain(project_path)
        if domain:
            print(f"    Detected: {domain}")
        else:
            print(f"ERROR: Could not auto-detect domain. Pass --domain explicitly.")
            print(f"  Valid: {', '.join(valid_domains)}")
            sys.exit(1)

    if domain not in valid_domains:
        print(f"ERROR: Unknown domain '{domain}'. Valid: {', '.join(valid_domains)}")
        sys.exit(1)

    # ── Step 3: Topic ID lookup (auto-create if new domain) ───────────────────
    print(f"==> Looking up topic for domain '{domain}' ...")
    topics = _api_get("/topics/?status=active")
    match = next((t for t in topics if t.get("domain_slug") == domain), None)
    if not match:
        print(f"    No topic found — creating one for domain '{domain}' ...")
        slug = re.sub(r"[^a-z0-9]+", "-", domain.lower()).strip("-")
        try:
            match = _api_post("/topics/", {
                "slug": slug,
                "title": project_name,
                "domain": domain,
                "status": "active",
            })
            print(f"    Topic created: {match['title']} ({match['id']})")
        except Exception as e:
            print(f"ERROR: Could not create topic for domain '{domain}': {e}")
            sys.exit(1)
    topic_id = match["id"]
    print(f"    topic_id: {topic_id}")

    # ── Step 4: MCP check ──────────────────────────────────────────────────────
    print("==> Checking MCP server registration ...")
    if _check_mcp():
        print("    MCP OK")
    else:
        print("WARNING: 'state-hub' not in ~/.claude.json.")
        print(f"  See ~/.claude/CLAUDE.md → MCP Server Registration section.")

    # ── Step 5: CLAUDE.md ──────────────────────────────────────────────────────
    claude_md = project_path / "CLAUDE.md"
    if claude_md.exists():
        print(f"==> CLAUDE.md already exists at {claude_md} — skipping.")
    else:
        print(f"==> Writing CLAUDE.md to {claude_md} ...")
        content = TEMPLATE.read_text()
        content = content.replace("{PROJECT_NAME}", project_name)
        content = content.replace("{DOMAIN}", domain)
        content = content.replace("{TOPIC_ID}", topic_id)
        claude_md.write_text(content)
        print("    Written.")

    # ── Step 6: Progress event ─────────────────────────────────────────────────
    print("==> Recording registration event ...")
    try:
        _api_post("/progress/", {
            "topic_id": topic_id,
            "event_type": "milestone",
            "summary": f"Project registered with State Hub: {project_name} ({domain})",
            "author": "custodian",
            "detail": {
                "project_path": str(project_path),
                "claude_md": str(claude_md),
                "domain": domain,
            },
        })
        print("    Event recorded.")
    except Exception as e:
        print(f"    WARNING: Could not record progress event: {e}")

    print()
    print("Registration complete!")
    print(f"  Project:   {project_name}")
    print(f"  Domain:    {domain}")
    print(f"  Topic ID:  {topic_id}")
    print(f"  CLAUDE.md: {claude_md}")
    print()
    print("Next: restart Claude Code for the MCP server to be active in this project.")


def cmd_create_workstream(args: argparse.Namespace) -> None:
    """Create a workstream under a domain's topic."""
    _api_get("/state/health")

    # Resolve topic_id from domain
    topics = _api_get("/topics/?status=active")
    match = next((t for t in topics if t.get("domain_slug") == args.domain), None)
    if not match:
        print(f"ERROR: No active topic for domain '{args.domain}'.")
        sys.exit(1)
    topic_id = match["id"]

    slug = args.slug or re.sub(r"[^a-z0-9]+", "-", args.title.lower()).strip("-")

    ws = _api_post("/workstreams/", {
        "topic_id": topic_id,
        "title": args.title,
        "slug": slug,
        "description": args.description,
        "owner": args.owner,
        "status": "active",
    })
    _api_post("/progress/", {
        "topic_id": topic_id,
        "workstream_id": ws["id"],
        "event_type": "workstream_created",
        "summary": f"Workstream created: {args.title}",
        "author": "custodian",
        "detail": {"owner": args.owner, "slug": slug},
    })
    print(f"Created workstream: {ws['title']}")
    print(f"  id:     {ws['id']}")
    print(f"  slug:   {ws['slug']}")
    print(f"  domain: {args.domain}")
    print(f"  owner:  {ws.get('owner') or '—'}")


def cmd_create_task(args: argparse.Namespace) -> None:
    """Create a task under a workstream (by ID or slug)."""
    _api_get("/state/health")

    # Resolve workstream: accept UUID or slug
    workstream_id = args.workstream
    if not _is_uuid(workstream_id):
        wss = _api_get("/workstreams/")
        match = next((w for w in wss if w.get("slug") == workstream_id), None)
        if not match:
            print(f"ERROR: No workstream found with slug '{workstream_id}'.")
            print("  Use 'custodian status' or check the dashboard for valid slugs.")
            sys.exit(1)
        workstream_id = match["id"]

    task = _api_post("/tasks/", {
        "workstream_id": workstream_id,
        "title": args.title,
        "priority": args.priority,
        "description": args.description,
        "assignee": args.assignee,
    })
    _api_post("/progress/", {
        "workstream_id": workstream_id,
        "task_id": task["id"],
        "event_type": "task_created",
        "summary": f"Task created: {args.title}",
        "author": "custodian",
        "detail": {"priority": args.priority},
    })
    print(f"Created task: {task['title']}")
    print(f"  id:       {task['id']}")
    print(f"  priority: {task['priority']}")
    print(f"  status:   {task['status']}")


def _is_uuid(s: str) -> bool:
    import uuid as _uuid
    try:
        _uuid.UUID(s)
        return True
    except ValueError:
        return False


def cmd_status(_args: argparse.Namespace) -> None:
    """Quick status: API health + summary totals."""
    health = _api_get("/state/health")
    print(f"API: {health.get('status', '?')}  DB: {health.get('db', '?')}")
    summary = _api_get("/state/summary")
    t = summary["totals"]
    print(f"Topics: {t['topics']['active']} active")
    print(f"Workstreams: {t['workstreams']['active']} active, {t['workstreams']['blocked']} blocked")
    print(f"Tasks: {t['tasks']['in_progress']} in-progress, {t['tasks']['todo']} todo, {t['tasks']['blocked']} blocked")
    print(f"Decisions: {t['decisions']['open']} open, {t['decisions']['escalated']} escalated")
    blocking = summary.get("blocking_decisions", [])
    if blocking:
        print(f"\nBlocking decisions ({len(blocking)}):")
        for d in blocking:
            deadline = d.get("deadline") or "no deadline"
            print(f"  [{deadline}] {d['title']}")


# ── Entry point ────────────────────────────────────────────────────────────────

def main() -> None:
    parser = argparse.ArgumentParser(
        prog="custodian",
        description="Custodian State Hub CLI",
    )
    sub = parser.add_subparsers(dest="command", required=True)

    # register-project
    reg = sub.add_parser("register-project", help="Register a project with the State Hub")
    reg.add_argument(
        "--domain",
        default=None,
        help="Project domain slug (auto-detected from charter if omitted)",
    )
    reg.add_argument(
        "--path",
        default=os.getcwd(),
        help="Project directory (defaults to current directory)",
    )

    # create-workstream
    cws = sub.add_parser("create-workstream", help="Create a workstream under a domain topic")
    cws.add_argument("--domain", required=True, help="Domain slug to create the workstream under")
    cws.add_argument("--title", required=True, help="Workstream title")
    cws.add_argument("--slug", default=None, help="URL slug (auto-generated from title if omitted)")
    cws.add_argument("--owner", default=None, help="Owner name")
    cws.add_argument("--description", default=None, help="Optional description")

    # create-task
    ctask = sub.add_parser("create-task", help="Create a task under a workstream")
    ctask.add_argument("--workstream", required=True, metavar="ID_OR_SLUG", help="Workstream UUID or slug")
    ctask.add_argument("--title", required=True, help="Task title")
    ctask.add_argument("--priority", choices=["low", "medium", "high", "critical"], default="medium")
    ctask.add_argument("--assignee", default=None)
    ctask.add_argument("--description", default=None)

    # status
    sub.add_parser("status", help="Show State Hub health and summary totals")

    args = parser.parse_args()

    if args.command == "register-project":
        cmd_register(args)
    elif args.command == "create-workstream":
        cmd_create_workstream(args)
    elif args.command == "create-task":
        cmd_create_task(args)
    elif args.command == "status":
        cmd_status(args)


if __name__ == "__main__":
    main()