package cmd

import (
	"context"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"strings"

	"github.com/charmbracelet/huh"
	"github.com/fatih/color"
	"github.com/google/uuid"
	"github.com/spf13/cobra"
	"github.com/torrentclaw/torrentclaw-cli/internal/agent"
	"github.com/torrentclaw/torrentclaw-cli/internal/config"
)

func newSetupCmd() *cobra.Command {
	var apiURL string

	cmd := &cobra.Command{
		Use:   "setup",
		Short: "First-time configuration wizard",
		Long: `Interactive setup that configures API key, download directory, and
preferred download method.

Opens your browser to create/copy your API key, then walks you through
choosing a download directory, method (torrent, debrid, usenet), and
device name. Validates the API key against the server before saving.

Run this once after installing unarr. To change settings later,
use 'unarr config' or edit ~/.config/unarr/config.toml directly.`,
		Example: `  unarr setup
  unarr setup --api-url https://custom.server.com`,
		RunE: func(cmd *cobra.Command, args []string) error {
			return runSetup(apiURL)
		},
	}

	cmd.Flags().StringVar(&apiURL, "api-url", "", "API URL override (default: https://torrentclaw.com)")

	return cmd
}

func runSetup(apiURLOverride string) error {
	bold := color.New(color.Bold)
	green := color.New(color.FgGreen)
	cyan := color.New(color.FgCyan)

	fmt.Println()
	bold.Println("  unarr Setup")
	fmt.Println()

	cfg := loadConfig()

	// Determine API URL
	apiURL := cfg.Auth.APIURL
	if apiURLOverride != "" {
		apiURL = apiURLOverride
	}
	if apiURL == "" {
		apiURL = "https://torrentclaw.com"
	}

	// Open browser to API keys page
	keysURL := apiURL + "/profile?tab=apikey"
	fmt.Printf("  Opening %s ...\n", keysURL)
	openBrowser(keysURL)
	fmt.Println()

	// Step 1: API Key
	apiKey := cfg.Auth.APIKey
	err := huh.NewForm(
		huh.NewGroup(
			huh.NewInput().
				Title("API Key").
				Description("Copy it from the page that just opened in your browser").
				Placeholder("tc_...").
				Value(&apiKey).
				Validate(func(s string) error {
					s = strings.TrimSpace(s)
					if s == "" {
						return fmt.Errorf("API key is required")
					}
					if !strings.HasPrefix(s, "tc_") {
						return fmt.Errorf("API key should start with tc_")
					}
					return nil
				}),
		),
	).Run()
	if err != nil {
		return err
	}
	apiKey = strings.TrimSpace(apiKey)

	// Validate API key by registering with the server
	fmt.Print("  Verifying API key... ")

	agentID := cfg.Agent.ID
	if agentID == "" {
		agentID = uuid.New().String()
	}

	hostname, _ := os.Hostname()
	agentName := cfg.Agent.Name
	if agentName == "" {
		agentName = hostname
	}

	ac := agent.NewClient(apiURL, apiKey, "unarr/"+Version)
	resp, err := ac.Register(context.Background(), agent.RegisterRequest{
		AgentID:     agentID,
		Name:        agentName,
		OS:          runtime.GOOS,
		Arch:        runtime.GOARCH,
		Version:     Version,
		DownloadDir: cfg.Download.Dir,
	})
	if err != nil {
		color.Red("FAILED")
		fmt.Println()
		return fmt.Errorf("API key validation failed: %w", err)
	}

	green.Println("OK")
	fmt.Printf("  Connected as %s (%s) [%s]\n", resp.User.Name, resp.User.Email, strings.ToUpper(resp.User.Plan))
	fmt.Println()

	// Step 2: Download directory
	downloadDir := cfg.Download.Dir
	if downloadDir == "" {
		downloadDir = defaultDownloadDir()
	}
	err = huh.NewForm(
		huh.NewGroup(
			huh.NewInput().
				Title("Download Directory").
				Description("Where should downloaded files be saved?").
				Value(&downloadDir),
		),
	).Run()
	if err != nil {
		return err
	}
	downloadDir = expandHome(strings.TrimSpace(downloadDir))

	// Step 3: Preferred download method
	method := cfg.Download.PreferredMethod
	if method == "" {
		method = "auto"
	}

	methodOptions := []huh.Option[string]{
		huh.NewOption("Auto (torrent, debrid when available)", "auto"),
		huh.NewOption("Torrent only (BitTorrent P2P)", "torrent"),
	}
	if resp.Features.Debrid {
		methodOptions = append(methodOptions,
			huh.NewOption("Debrid only (Real-Debrid, AllDebrid...)", "debrid"),
		)
	}
	if resp.Features.Usenet {
		methodOptions = append(methodOptions,
			huh.NewOption("Usenet only (requires Pro)", "usenet"),
		)
	}

	err = huh.NewForm(
		huh.NewGroup(
			huh.NewSelect[string]().
				Title("Download Method").
				Description("How do you want to download?").
				Options(methodOptions...).
				Value(&method),
		),
	).Run()
	if err != nil {
		return err
	}

	// Step 4: Agent name
	err = huh.NewForm(
		huh.NewGroup(
			huh.NewInput().
				Title("Device Name").
				Description("A name for this machine (shown in the web dashboard)").
				Value(&agentName),
		),
	).Run()
	if err != nil {
		return err
	}

	// Save config
	cfg.Auth.APIKey = apiKey
	cfg.Auth.APIURL = apiURL
	cfg.Agent.ID = agentID
	cfg.Agent.Name = strings.TrimSpace(agentName)
	cfg.Download.Dir = downloadDir
	cfg.Download.PreferredMethod = method

	// Set organize dirs based on download dir
	if cfg.Organize.MoviesDir == "" {
		cfg.Organize.MoviesDir = filepath.Join(downloadDir, "Movies")
	}
	if cfg.Organize.TVShowsDir == "" {
		cfg.Organize.TVShowsDir = filepath.Join(downloadDir, "TV Shows")
	}

	// Validate paths before saving
	if err := cfg.ValidatePaths(); err != nil {
		return fmt.Errorf("unsafe configuration: %w", err)
	}

	configPath := config.FilePath()
	if cfgFile != "" {
		configPath = cfgFile
	}

	if err := config.Save(cfg, configPath); err != nil {
		return fmt.Errorf("save config: %w", err)
	}

	// Summary
	fmt.Println()
	green.Println("  Setup complete!")
	fmt.Println()
	fmt.Printf("  User:      %s (%s) [%s]\n", resp.User.Name, resp.User.Email, strings.ToUpper(resp.User.Plan))
	fmt.Printf("  Downloads: %s\n", downloadDir)
	fmt.Printf("  Method:    %s\n", method)
	fmt.Printf("  Agent:     %s (%s)\n", agentName, agentID[:8]+"...")
	fmt.Printf("  Config:    %s\n", configPath)
	fmt.Println()

	// Features summary
	features := []string{}
	if resp.Features.Torrent {
		features = append(features, "Torrent")
	}
	if resp.Features.Debrid {
		features = append(features, "Debrid")
	}
	if resp.Features.Usenet {
		features = append(features, "Usenet")
	}
	cyan.Printf("  Available: %s\n", strings.Join(features, ", "))
	fmt.Println()
	fmt.Println("  Next: run", bold.Sprint("unarr start"), "to begin downloading")
	fmt.Println()

	return nil
}

// openBrowser opens a URL in the default browser.
func openBrowser(url string) {
	var cmd *exec.Cmd
	switch runtime.GOOS {
	case "darwin":
		cmd = exec.Command("open", url)
	case "windows":
		cmd = exec.Command("rundll32", "url.dll,FileProtocolHandler", url)
	default: // linux, freebsd
		cmd = exec.Command("xdg-open", url)
	}
	cmd.Start() // fire and forget
}

func defaultDownloadDir() string {
	home, _ := os.UserHomeDir()
	candidates := []string{
		filepath.Join(home, "Media"),
		filepath.Join(home, "Downloads", "unarr"),
	}
	for _, d := range candidates {
		if fi, err := os.Stat(d); err == nil && fi.IsDir() {
			return d
		}
	}
	return filepath.Join(home, "Media")
}

func expandHome(path string) string {
	if strings.HasPrefix(path, "~/") {
		home, _ := os.UserHomeDir()
		return filepath.Join(home, path[2:])
	}
	return path
}