#!/usr/bin/env python3
"""
Cauldron Cloud MCP — Setup wizard
Creates a local virtual environment, installs dependencies,
and writes Claude Desktop config automatically.
"""

import json
import os
import platform
import shutil
import subprocess
import sys
import webbrowser
from pathlib import Path

# ── Colours ──────────────────────────────────────────────────────────────────

def _supports_colour() -> bool:
    return sys.stdout.isatty() and platform.system() != "Windows"

if _supports_colour():
    RESET  = "\033[0m"
    BOLD   = "\033[1m"
    GREEN  = "\033[32m"
    YELLOW = "\033[33m"
    RED    = "\033[31m"
    CYAN   = "\033[36m"
else:
    RESET = BOLD = GREEN = YELLOW = RED = CYAN = ""

def ok(msg: str)   -> None: print(f"{GREEN}  ✓  {RESET}{msg}")
def info(msg: str) -> None: print(f"{CYAN}  →  {RESET}{msg}")
def warn(msg: str) -> None: print(f"{YELLOW}  ⚠  {RESET}{msg}")
def err(msg: str)  -> None: print(f"{RED}  ✗  {RESET}{msg}")
def bold(msg: str) -> str:  return f"{BOLD}{msg}{RESET}"

# ── Paths ─────────────────────────────────────────────────────────────────────

REPO_DIR   = Path(__file__).resolve().parent
VENV_DIR   = REPO_DIR / ".venv"
SERVER_PY  = REPO_DIR / "server.py"
PACKAGES   = ["mcp>=1.0.0", "httpx>=0.27.0"]


def _venv_python() -> Path:
    """Path to the Python executable inside the local venv."""
    if platform.system() == "Windows":
        return VENV_DIR / "Scripts" / "python.exe"
    return VENV_DIR / "bin" / "python"


def _config_path() -> Path:
    system = platform.system()
    if system == "Windows":
        base = Path(os.environ.get("APPDATA", "~")).expanduser()
        return base / "Claude" / "claude_desktop_config.json"
    if system == "Darwin":
        return Path.home() / "Library" / "Application Support" / "Claude" / "claude_desktop_config.json"
    xdg = os.environ.get("XDG_CONFIG_HOME", "")
    base = Path(xdg) if xdg else Path.home() / ".config"
    return base / "Claude" / "claude_desktop_config.json"


def _read_config(path: Path) -> dict:
    if path.exists():
        try:
            return json.loads(path.read_text(encoding="utf-8"))
        except json.JSONDecodeError:
            warn("Existing config file contains invalid JSON — backing it up.")
            backup = path.with_suffix(".json.bak")
            shutil.copy(path, backup)
            info(f"Backup saved to {backup}")
    return {}


def _write_config(path: Path, data: dict) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(json.dumps(data, indent=2, ensure_ascii=False), encoding="utf-8")


def _validate_key(key: str) -> bool:
    key = key.strip()
    return key.startswith("cldrn_") and len(key) >= 20


# ── Venv + deps ───────────────────────────────────────────────────────────────

def _create_venv() -> bool:
    info(f"Creating virtual environment in {VENV_DIR} ...")
    result = subprocess.run(
        [sys.executable, "-m", "venv", str(VENV_DIR)],
        capture_output=True, text=True,
    )
    if result.returncode != 0:
        err("Could not create virtual environment:")
        print(result.stderr.strip())
        return False
    return True


def _install_deps() -> bool:
    python = _venv_python()
    info("Installing dependencies into virtual environment...")
    result = subprocess.run(
        [str(python), "-m", "pip", "install", "--quiet", "--upgrade", *PACKAGES],
        capture_output=True, text=True,
    )
    if result.returncode != 0:
        err("pip install failed:")
        print(result.stderr.strip())
        return False
    return True


def _deps_ok() -> bool:
    python = _venv_python()
    if not python.exists():
        return False
    result = subprocess.run(
        [str(python), "-c", "import mcp, httpx"],
        capture_output=True,
    )
    return result.returncode == 0


# ── Main ──────────────────────────────────────────────────────────────────────

def main() -> None:
    print()
    print(bold("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"))
    print(bold("  Cauldron Cloud — MCP Server Setup"))
    print(bold("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"))
    print()

    # ── 1. Python version ─────────────────────────────────────────────────────
    if sys.version_info < (3, 10):
        err(f"Python 3.10+ required (you have {platform.python_version()}).")
        sys.exit(1)
    ok(f"Python {platform.python_version()}")

    # ── 2. server.py present ──────────────────────────────────────────────────
    if not SERVER_PY.exists():
        err(f"server.py not found at {SERVER_PY}")
        sys.exit(1)
    ok(f"Server script: {SERVER_PY}")

    # ── 3. Virtual environment + dependencies ─────────────────────────────────
    if _deps_ok():
        ok("Virtual environment already set up")
    else:
        if VENV_DIR.exists():
            info("Refreshing existing virtual environment...")
        elif not _create_venv():
            sys.exit(1)

        if not _install_deps() or not _deps_ok():
            err("Could not install dependencies. Check your Python installation.")
            sys.exit(1)
        ok("Dependencies installed (mcp, httpx)")

    python_cmd = str(_venv_python())

    # ── 4. API key ────────────────────────────────────────────────────────────
    print()
    print(bold("  Step: Generate your API key"))
    print()
    print("  A browser window will open to the Cauldron portal.")
    print("  Log in, click  Generate , copy the key and paste it below.")
    print()
    input("  Press ENTER to open the browser...")

    webbrowser.open("https://cauldron.cloud/mcpKeys")
    info("Opened: https://cauldron.cloud/mcpKeys")
    print()

    api_key = ""
    for _ in range(3):
        raw = input("  Paste your API key here: ").strip()
        if _validate_key(raw):
            api_key = raw
            break
        err("Key must start with  cldrn_  and be at least 20 characters. Try again.")
    else:
        err("No valid key provided. Run setup.py again when you have a key.")
        sys.exit(1)

    ok(f"Key accepted: {api_key[:14]}…")

    # ── 5. Write Claude Desktop config ────────────────────────────────────────
    config_path = _config_path()
    print()
    info(f"Config file: {config_path}")

    config  = _read_config(config_path)
    existing = config.get("mcpServers", {}).get("cauldron")

    config.setdefault("mcpServers", {})["cauldron"] = {
        "command": python_cmd,
        "args":    [str(SERVER_PY)],
        "env":     {"CAULDRON_API_KEY": api_key},
    }

    _write_config(config_path, config)

    if existing:
        ok("Updated existing  cauldron  entry in Claude Desktop config")
    else:
        ok("Added  cauldron  entry to Claude Desktop config")

    # ── 6. Done ───────────────────────────────────────────────────────────────
    print()
    print(bold("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"))
    print(bold("  Setup complete!"))
    print(bold("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"))
    print()
    print("  Next steps:")
    print(f"  1. {bold('Restart Claude Desktop')}")
    print("  2. Open a new Chat")
    print("  3. Look for the 🔌 icon — cauldron should appear in the tool list")
    print()
    print("  Try asking Claude:")
    print(f"    {CYAN}\"Show me all open Sell Side deals in the Automotive sector\"{RESET}")
    print(f"    {CYAN}\"Are there any incoming Requests for Help we haven't answered?\"{RESET}")
    print()
    print(f"  To update in the future:  {bold('git pull')}  (then restart Claude Desktop)")
    print()


if __name__ == "__main__":
    main()