import asyncio
import atexit
import json
import logging
import os
import shutil
import subprocess
from typing import Annotated, List, Literal, Optional

import psutil
import typer
import uvicorn
from dotenv import load_dotenv, set_key
from rich.panel import Panel
from rich.prompt import Confirm
from starlette.middleware import Middleware

from skyvern.cli.console import console
from skyvern.cli.core.client import close_skyvern
from skyvern.cli.core.mcp_http_auth import MCPAPIKeyMiddleware, close_auth_db
from skyvern.cli.core.session_manager import close_current_session, set_stateless_http_mode
from skyvern.cli.mcp_tools import mcp  # Uses standalone fastmcp (v2.x)
from skyvern.cli.utils import start_services
from skyvern.config import settings
from skyvern.forge.sdk.core import skyvern_context
from skyvern.forge.sdk.forge_log import setup_logger
from skyvern.services.script_service import run_script
from skyvern.utils import detect_os
from skyvern.utils.env_paths import resolve_backend_env_path, resolve_frontend_env_path

run_app = typer.Typer(help="Commands to run Skyvern services such as the API server or UI.")
_mcp_cleanup_done = False


async def _cleanup_mcp_resources() -> None:
    try:
        await close_current_session()
    finally:
        try:
            await close_skyvern()
        finally:
            await close_auth_db()


def _cleanup_mcp_resources_blocking() -> None:
    global _mcp_cleanup_done
    if _mcp_cleanup_done:
        return

    try:
        asyncio.run(_cleanup_mcp_resources())
        _mcp_cleanup_done = True
    except Exception:
        logging.getLogger(__name__).warning("MCP cleanup failed", exc_info=True)


def _cleanup_mcp_resources_sync() -> None:
    """Atexit callback for MCP cleanup. Skips if an event loop is still running
    because asyncio.run() cannot be called inside a running loop. This means
    cleanup is best-effort for signal-based exits (e.g. SIGTERM) that fire atexit
    while the MCP server's loop is still alive -- the finally block in run_mcp()
    handles normal shutdown instead."""
    logger = logging.getLogger(__name__)
    try:
        asyncio.get_running_loop()
    except RuntimeError:
        _cleanup_mcp_resources_blocking()
        return

    logger.debug("Skipping MCP cleanup because event loop is still running")


def get_pids_on_port(port: int) -> List[int]:
    """Return a list of PIDs listening on the given port."""
    pids = []
    try:
        for conn in psutil.net_connections(kind="inet"):
            if conn.laddr and conn.laddr.port == port and conn.pid:
                pids.append(conn.pid)
    except Exception:
        pass
    return list(set(pids))


def kill_pids(pids: List[int]) -> None:
    """Kill the given list of PIDs in a cross-platform way."""
    host_system = detect_os()
    for pid in pids:
        try:
            if host_system in {"windows", "wsl"}:
                subprocess.run(f"taskkill /PID {pid} /F", shell=True, check=False)
            else:
                os.kill(pid, 9)
        except Exception:
            console.print(f"[red]Failed to kill process {pid}[/red]")


@run_app.command(name="server")
def run_server() -> None:
    """Run the Skyvern API server."""
    load_dotenv(resolve_backend_env_path())
    from skyvern.config import settings  # noqa: PLC0415

    port = settings.PORT
    console.print(Panel(f"[bold green]Starting Skyvern API Server on port {port}...", border_style="green"))
    uvicorn.run(
        "skyvern.forge.api_app:create_api_app",
        host="0.0.0.0",
        port=port,
        log_level="info",
        factory=True,
    )


@run_app.command(name="ui")
def run_ui() -> None:
    """Run the Skyvern UI server."""
    console.print(Panel("[bold blue]Starting Skyvern UI Server...[/bold blue]", border_style="blue"))
    try:
        with console.status("[bold green]Checking for existing process on port 8080...") as status:
            pids = get_pids_on_port(8080)
            if pids:
                status.stop()
                response = Confirm.ask("Process already running on port 8080. [yellow]Kill it?[/yellow]")
                if response:
                    kill_pids(pids)
                    console.print("✅ [green]Process killed.[/green]")
                else:
                    console.print("[yellow]UI server not started. Process already running on port 8080.[/yellow]")
                    return
            status.stop()
    except Exception as e:  # pragma: no cover - CLI safeguards
        console.print(f"[red]Error checking for process: {e}[/red]")

    frontend_env_path = resolve_frontend_env_path()
    if frontend_env_path is None:
        console.print("[bold red]ERROR: Skyvern Frontend directory not found.[/bold red]")
        return

    frontend_dir = frontend_env_path.parent
    if not frontend_env_path.exists():
        console.print("[bold blue]Setting up frontend .env file...[/bold blue]")
        shutil.copy(frontend_dir / ".env.example", frontend_env_path)
        console.print("✅ [green]Successfully set up frontend .env file[/green]")

    backend_env_path = resolve_backend_env_path()
    if backend_env_path.exists():
        load_dotenv(backend_env_path)
        skyvern_api_key = os.getenv("SKYVERN_API_KEY")
        if skyvern_api_key:
            set_key(frontend_env_path, "VITE_SKYVERN_API_KEY", skyvern_api_key)
        else:
            console.print("[red]ERROR: SKYVERN_API_KEY not found in .env file[/red]")
    else:
        console.print(f"[red]ERROR: Backend .env file not found at {backend_env_path}[/red]")

    os.chdir(frontend_dir)

    try:
        console.print("📦 [bold blue]Running npm install...[/bold blue]")
        subprocess.run("npm install --silent", shell=True, check=True)
        console.print("✅ [green]npm install complete.[/green]")
        console.print("🚀 [bold blue]Starting npm UI server...[/bold blue]")
        subprocess.run("npm run start", shell=True, check=True)
    except subprocess.CalledProcessError as e:
        console.print(f"[bold red]Error running UI server: {e}[/bold red]")
        return


@run_app.command(name="ui-dev")
def run_ui_dev() -> None:
    """Run the Skyvern UI server in development mode (npm run start-local)."""
    console.print(Panel("[bold blue]Starting Skyvern UI Server (dev mode)...[/bold blue]", border_style="blue"))
    try:
        with console.status("[bold green]Checking for existing process on port 8080...") as status:
            pids = get_pids_on_port(8080)
            if pids:
                status.stop()
                response = Confirm.ask("Process already running on port 8080. [yellow]Kill it?[/yellow]")
                if response:
                    kill_pids(pids)
                    console.print("✅ [green]Process killed.[/green]")
                else:
                    console.print("[yellow]UI server not started. Process already running on port 8080.[/yellow]")
                    return
            status.stop()
    except Exception as e:  # pragma: no cover - CLI safeguards
        console.print(f"[red]Error checking for process: {e}[/red]")

    frontend_env_path = resolve_frontend_env_path()
    if frontend_env_path is None:
        console.print("[bold red]ERROR: Skyvern Frontend directory not found.[/bold red]")
        return

    frontend_dir = frontend_env_path.parent

    os.chdir(frontend_dir)

    try:
        console.print("📦 [bold blue]Running npm ci...[/bold blue]")
        subprocess.run("npm ci", shell=True, check=True)
        console.print("✅ [green]npm ci complete.[/green]")
        console.print("🚀 [bold blue]Starting npm UI server (start-local)...[/bold blue]")
        subprocess.run("npm run start-local", shell=True, check=True)
    except subprocess.CalledProcessError as e:
        console.print(f"[bold red]Error running UI server: {e}[/bold red]")
        return


@run_app.command(name="all")
def run_all() -> None:
    """Run the Skyvern API server and UI server in parallel."""
    asyncio.run(start_services())


@run_app.command(name="dev")
def run_dev() -> None:
    """Run the Skyvern API server and UI server in the background (detached).

    This command starts both services and immediately returns control to your terminal.
    Use 'skyvern stop all' to stop the services.
    """
    load_dotenv(resolve_backend_env_path())
    from skyvern.config import settings as skyvern_settings  # noqa: PLC0415

    console.print(Panel("[bold green]Starting Skyvern in development mode...[/bold green]", border_style="green"))

    # Start server in background (detached) - call uvicorn directly
    server_process = subprocess.Popen(
        [
            "uvicorn",
            "skyvern.forge.api_app:create_api_app",
            "--host",
            "0.0.0.0",
            "--port",
            str(skyvern_settings.PORT),
            "--factory",
        ],
        stdout=subprocess.DEVNULL,
        stderr=subprocess.DEVNULL,
        start_new_session=True,
    )
    console.print(f"✅ [green]Server started in background (PID: {server_process.pid})[/green]")

    # Start UI (dev mode) in background (detached) - call npm directly
    frontend_env_path = resolve_frontend_env_path()
    if frontend_env_path is None:
        console.print("[bold red]ERROR: Skyvern Frontend directory not found.[/bold red]")
        return
    frontend_dir = frontend_env_path.parent

    ui_process = subprocess.Popen(
        ["npm", "run", "start-local"],
        cwd=frontend_dir,
        stdout=subprocess.DEVNULL,
        stderr=subprocess.DEVNULL,
        start_new_session=True,
    )
    console.print(f"✅ [green]UI (dev mode) started in background (PID: {ui_process.pid})[/green]")

    console.print("\n🎉 [bold green]Skyvern is starting![/bold green]")
    console.print(f"🌐 [bold]API server:[/bold] [cyan]http://localhost:{skyvern_settings.PORT}[/cyan]")
    console.print("🖥️  [bold]UI:[/bold] [cyan]http://localhost:8080[/cyan]")
    console.print("\n[dim]Use 'skyvern stop all' to stop the services.[/dim]")


@run_app.command(name="mcp")
def run_mcp(
    transport: Annotated[
        Literal["stdio", "sse", "streamable-http"],
        typer.Option(
            "--transport",
            help="MCP transport: stdio (default), sse, or streamable-http.",
        ),
    ] = "stdio",
    host: Annotated[str, typer.Option("--host", help="Host for HTTP transports.")] = "0.0.0.0",
    port: Annotated[int, typer.Option("--port", help="Port for HTTP transports.")] = 8000,
    path: Annotated[str, typer.Option("--path", help="HTTP endpoint path for MCP transport.")] = "/mcp",
    stateless_http: Annotated[
        bool,
        typer.Option(
            "--stateless-http/--no-stateless-http",
            help="Use stateless HTTP semantics for HTTP transports (ignored for stdio).",
        ),
    ] = True,
) -> None:
    """Run the MCP server with configurable transport for local or remote hosting."""
    path = _normalize_mcp_path(path)
    stateless_http_enabled = transport != "stdio" and stateless_http
    # atexit covers signal-based exits (SIGTERM); finally covers normal
    # mcp.run() completion or unhandled exceptions. Both are needed because
    # atexit doesn't fire on normal return and finally doesn't fire on signals.
    atexit.register(_cleanup_mcp_resources_sync)
    set_stateless_http_mode(stateless_http_enabled)
    try:
        if transport == "stdio":
            mcp.run(transport="stdio")
            return

        middleware = [Middleware(MCPAPIKeyMiddleware)]
        mcp.run(
            transport=transport,
            host=host,
            port=port,
            path=path,
            middleware=middleware,
            stateless_http=stateless_http_enabled,
        )
    finally:
        set_stateless_http_mode(False)
        _cleanup_mcp_resources_blocking()


def _normalize_mcp_path(path: str) -> str:
    path = path.strip()
    if not path:
        return "/mcp"
    if not path.startswith("/"):
        return f"/{path}"
    return path


@run_app.command(
    name="code",
    context_settings={"allow_interspersed_args": False},
)
def run_code(
    script_path: str = typer.Argument(..., help="Path to the Python script to run"),
    params: List[str] = typer.Option([], "-p", help="Parameters in format param=value (without leading dash)"),
    params_json: str = typer.Option(None, "--params", help="JSON string of parameters"),
    params_file: str = typer.Option(None, "--params-file", help="Path to JSON file with parameters"),
    ai: Optional[str] = typer.Option(
        "fallback", "--ai", help="AI mode to use for the script. Options: fallback, proactive or None"
    ),
) -> None:
    """Run a Python script with parameters.

    Supports three ways to pass parameters (in order of priority):

    1. JSON file (highest priority):
        skyvern run code main.py --params-file params.json

    2. JSON string:
        skyvern run code main.py --params '{"param1": "val1", "param2": "val2"}'

    3. Individual flags (lowest priority):
        skyvern run code main.py -p param1=val1 -p param2=val2

    Note: For backward compatibility, leading dashes in -p values are automatically stripped.
    """
    # Disable LiteLLM loggers
    os.environ["LITELLM_LOG"] = "CRITICAL"
    import litellm  # noqa: PLC0415

    litellm.suppress_debug_info = True
    litellm.set_verbose = False

    logging.getLogger("LiteLLM").setLevel(logging.CRITICAL)
    logging.getLogger("LiteLLM Router").setLevel(logging.CRITICAL)
    logging.getLogger("LiteLLM Proxy").setLevel(logging.CRITICAL)
    settings.LOG_LEVEL = "CRITICAL"
    setup_logger()

    # Validate script path
    if not script_path:
        console.print("[red]❌ Error: No script path provided[/red]")
        console.print("[yellow]→ Action: Provide a path to your Python script[/yellow]")
        console.print("[blue]Example: skyvern run code main.py -p param1=value1[/blue]")
        raise typer.Exit(code=1)

    if not os.path.exists(script_path):
        console.print("[red]❌ Error: Cannot find script file[/red]")
        console.print(f"[yellow]→ Looked for: {script_path}[/yellow]")
        console.print("[yellow]→ Action: Check that the file exists and the path is correct[/yellow]")
        # Show current directory to help user understand relative paths
        console.print(f"[blue]Current directory: {os.getcwd()}[/blue]")
        raise typer.Exit(code=1)

    if not script_path.endswith(".py"):
        console.print("[red]❌ Error: Invalid file type[/red]")
        console.print(f"[yellow]→ Provided: {script_path}[/yellow]")
        console.print("[yellow]→ Action: Please provide a Python script file ending with .py[/yellow]")
        console.print("[blue]Example: skyvern run code my_script.py[/blue]")
        raise typer.Exit(code=1)

    parameters = {}

    # Priority: params_file > params_json > individual -p flags
    if params_file:
        try:
            with open(params_file) as f:
                parameters = json.load(f)
            console.print(f"[blue]✓ Loaded parameters from file: {params_file}[/blue]")
        except FileNotFoundError:
            console.print("[red]❌ Error: Cannot find parameters file[/red]")
            console.print(f"[yellow]→ Looked for: {params_file}[/yellow]")
            console.print("[yellow]→ Action: Check that the file exists and the path is correct[/yellow]")
            console.print(f"[blue]Current directory: {os.getcwd()}[/blue]")
            raise typer.Exit(code=1)
        except json.JSONDecodeError as e:
            console.print("[red]❌ Error: Invalid JSON format in parameters file[/red]")
            console.print(f"[yellow]→ File: {params_file}[/yellow]")
            console.print(f"[yellow]→ Details: {e}[/yellow]")
            console.print("[yellow]→ Action: Fix the JSON syntax in your parameters file[/yellow]")
            console.print('[blue]Expected format: {{"param1": "value1", "param2": "value2"}}[/blue]')
            raise typer.Exit(code=1)
    elif params_json:
        try:
            parameters = json.loads(params_json)
            console.print("[blue]✓ Loaded parameters from JSON string[/blue]")
        except json.JSONDecodeError as e:
            console.print("[red]❌ Error: Invalid JSON format in --params string[/red]")
            console.print(f"[yellow]→ Details: {e}[/yellow]")
            console.print("[yellow]→ Action: Check your JSON syntax (quotes, brackets, commas)[/yellow]")
            console.print('[blue]Example: --params \'{{"param1": "value1", "param2": "value2"}}\'[/blue]')
            raise typer.Exit(code=1)
    elif params:
        for param in params:
            # Remove leading dash if present (for backward compatibility)
            if param.startswith("-"):
                param = param[1:]

            if "=" in param:
                key, value = param.split("=", 1)
                parameters[key] = value
            else:
                console.print("[yellow]⚠️  Warning: Skipping invalid parameter format[/yellow]")
                console.print(f"[yellow]→ Invalid: {param}[/yellow]")
                console.print("[yellow]→ Expected format: -p param=value[/yellow]")
                console.print("[blue]Example: -p download_start_date=31/07/2025[/blue]")
        console.print("[blue]✓ Loaded parameters from command-line flags[/blue]")

    console.print(Panel(f"[bold green]Running script: {script_path}[/bold green]", border_style="green"))
    if parameters:
        console.print("[blue]📋 Parameters:[/blue]")
        console.print(f"[blue]{json.dumps(parameters, indent=2)}[/blue]")
    else:
        console.print("[blue]ℹ️  Running script without parameters[/blue]")
        console.print("[dim]Tip: Add parameters with -p, --params, or --params-file[/dim]")

    # set up skyvern context

    skyvern_context.set(skyvern_context.SkyvernContext(script_mode=True, ai_mode_override=ai))
    try:
        asyncio.run(run_script(path=script_path, parameters=parameters))
        console.print("✅ [green]Script execution completed successfully![/green]")
    except Exception as e:
        console.print("[red]❌ Error: Script execution failed[/red]")
        console.print(f"[yellow]→ Script: {script_path}[/yellow]")
        console.print(f"[yellow]→ Details: {e}[/yellow]")
        console.print("[yellow]→ Action: Check the error message above and fix any issues in your script[/yellow]")
        raise typer.Exit(code=1)