"""Native Messaging host installation command."""
from __future__ import annotations

import json
import sys
from pathlib import Path

import click
from rich.console import Console

from browser_cli.constants import (
  ALLOWED_EXTENSION_IDS,
  EXTENSION_ID,
  NATIVE_HOST_DIRS,
  NATIVE_HOST_NAME,
  SUPPORTED_BROWSERS,
  WEBSTORE_EXTENSION_ID,
  WINDOWS_NATIVE_HOST_REGISTRY_KEYS,
)
from browser_cli.platform import install_base_dir, is_windows

console = Console()

def native_host_exe() -> Path:
  base = install_base_dir()
  if is_windows():
    return base / "libexec" / "browser-cli-native-host.cmd"
  return base / "libexec" / "browser-cli-native-host"

def write_native_host_exe(path: Path) -> None:
  path.parent.mkdir(parents=True, exist_ok=True)
  if is_windows():
    path.write_text(
      f'@echo off\r\n"{sys.executable}" -c "from browser_cli.native.host import main; main()" %*\r\n',
      encoding="utf-8",
    )
  else:
    path.write_text(f'#!{sys.executable}\nfrom browser_cli.native.host import main\nmain()\n')
    path.chmod(path.stat().st_mode | 0o111)

def _windows_registry_views():
  import winreg
  return [0, getattr(winreg, "KEY_WOW64_32KEY", 0), getattr(winreg, "KEY_WOW64_64KEY", 0)]

def _register_windows_native_host(browser: str, manifest_path: Path) -> list[str]:
  import winreg

  installed = []
  for key_path in WINDOWS_NATIVE_HOST_REGISTRY_KEYS[browser]:
    full_key = f"{key_path}\\{NATIVE_HOST_NAME}"
    for view in _windows_registry_views():
      try:
        access = winreg.KEY_WRITE | view
        key = winreg.CreateKeyEx(winreg.HKEY_CURRENT_USER, full_key, 0, access)
        with key:
          winreg.SetValueEx(key, "", 0, winreg.REG_SZ, str(manifest_path))
        installed.append(f"HKCU\\{full_key}")
      except OSError as e:
        console.print(f"[yellow]Could not write registry key {full_key}: {e}[/yellow]")
  return installed

@click.command("install")
@click.argument("browser", type=click.Choice(SUPPORTED_BROWSERS), default="chrome")
def cmd_install(browser):
  """Register the native messaging host and print extension load instructions."""
  host_exe = native_host_exe()
  write_native_host_exe(host_exe)

  ext_url = {
    "chrome": "chrome://extensions",
    "chromium": "chrome://extensions",
    "brave": "brave://extensions",
    "edge": "edge://extensions",
    "vivaldi": "vivaldi://extensions",
  }[browser]
  console.print("\n[bold]Step 1:[/bold] Load the extension in your browser")
  console.print(f"  1. Open [cyan]{ext_url}[/cyan]")
  console.print("  2. Enable [bold]Developer mode[/bold] (top-right toggle)")
  console.print(f"  3. Click [bold]Load unpacked[/bold] → select: [cyan]{Path(__file__).parent.parent.parent / 'extension'}[/cyan]")
  console.print(f"  4. Testing extension ID will be [cyan]{EXTENSION_ID}[/cyan] (fixed by built-in key)")
  console.print(f"     Chrome Web Store extension ID is [cyan]{WEBSTORE_EXTENSION_ID}[/cyan]\n")

  manifest = {
    "name": NATIVE_HOST_NAME,
    "description": "browser-cli native messaging host",
    "path": str(host_exe),
    "type": "stdio",
    "allowed_origins": [f"chrome-extension://{extension_id}/" for extension_id in ALLOWED_EXTENSION_IDS],
  }
  installed = _install_manifest(browser, host_exe, manifest)
  if not installed:
    console.print("[red]Failed to install native host manifest[/red]")
    sys.exit(1)

  for p in installed:
    label = "Registered native host" if is_windows() else "Wrote native host manifest"
    console.print(f"[green]✓[/green] {label}: {p}")
  console.print(f"[green]✓[/green] Installed native host: {host_exe}")
  console.print(f"\n[bold]Step 2:[/bold] Restart {browser.capitalize()} completely (quit app, then reopen)")
  console.print("\n[green bold]✓ Installation complete![/green bold]")
  console.print("  After restarting the browser, try: [cyan]browser-cli tabs list[/cyan]")

def _install_manifest(browser: str, host_exe: Path, manifest: dict) -> list:
  if is_windows():
    manifest_dir = host_exe.parent
    manifest_dir.mkdir(parents=True, exist_ok=True)
    manifest_path = manifest_dir / f"{NATIVE_HOST_NAME}.json"
    manifest_path.write_text(json.dumps(manifest, indent=2), encoding="utf-8")
    return _register_windows_native_host(browser, manifest_path)

  platform = "darwin" if sys.platform == "darwin" else "linux"
  installed = []
  for directory in NATIVE_HOST_DIRS[browser][platform]:
    try:
      directory.mkdir(parents=True, exist_ok=True)
      manifest_path = directory / f"{NATIVE_HOST_NAME}.json"
      manifest_path.write_text(json.dumps(manifest, indent=2))
      installed.append(manifest_path)
    except Exception as e:
      console.print(f"[yellow]Could not write to {directory}: {e}[/yellow]")
  return installed