package services

import (
	"context"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"sync"
	"time"
)

func CheckWorkshopMod(serverfileDir, modID string) bool {
	if modID == "" {
		return false
	}
	p := filepath.Join(serverfileDir, "steamapps", "workshop", "content", "107410", modID)
	fi, err := os.Stat(p)
	return err == nil && fi.IsDir()
}

const arma3AppID = "233780"

type SteamCmdManager struct {
	serverfileDir string
	streamer      *LogStreamer
	mu            sync.Mutex
	cancel        context.CancelFunc
	running       bool
}

func NewSteamCmdManager(serverfileDir string, streamer *LogStreamer) *SteamCmdManager {
	return &SteamCmdManager{
		serverfileDir: serverfileDir,
		streamer:      streamer,
	}
}

func (s *SteamCmdManager) IsRunning() bool {
	s.mu.Lock()
	defer s.mu.Unlock()
	return s.running
}

func (s *SteamCmdManager) UpdateGame(branch, user string) error {
	s.mu.Lock()
	if s.running {
		s.mu.Unlock()
		return fmt.Errorf("steamcmd already running")
	}
	s.mu.Unlock()

	args := []string{
		"+force_install_dir", s.serverfileDir,
		"+login", user,
		"+app_update", arma3AppID,
	}
	if branch != "" && branch != "stable" {
		args = append(args, "-beta", branch)
	}
	args = append(args, "validate", "+quit")

	return s.run("Game update", args)
}

func (s *SteamCmdManager) DownloadMod(modID string) error {
	return s.DownloadMods([]string{modID})
}

func (s *SteamCmdManager) DownloadMods(modIDs []string) error {
	s.mu.Lock()
	if s.running {
		s.mu.Unlock()
		return fmt.Errorf("steamcmd already running")
	}
	s.mu.Unlock()

	if len(modIDs) == 0 {
		return fmt.Errorf("no mod ids provided")
	}

	args := []string{
		"+force_install_dir", s.serverfileDir,
		"+login", "anonymous",
	}
	for _, id := range modIDs {
		args = append(args, "+workshop_download_item", "107410", id)
	}
	args = append(args, "+quit")

	label := fmt.Sprintf("Download %d mod(s)", len(modIDs))
	return s.run(label, args)
}

const steamcmdTimeout = 10 * time.Minute

func (s *SteamCmdManager) run(label string, args []string) error {
	ctx, cancel := context.WithTimeout(context.Background(), steamcmdTimeout)

	s.streamer.Broadcast("steamcmd", "[STEAMCMD] "+label+" starting...")

	cmd := exec.CommandContext(ctx, "steamcmd", args...)

	stdout, err := cmd.StdoutPipe()
	if err != nil {
		cancel()
		return fmt.Errorf("stdout pipe: %w", err)
	}
	stderr, err := cmd.StderrPipe()
	if err != nil {
		cancel()
		return fmt.Errorf("stderr pipe: %w", err)
	}

	if err := cmd.Start(); err != nil {
		cancel()
		return fmt.Errorf("start steamcmd: %w", err)
	}

	s.mu.Lock()
	s.running = true
	s.cancel = cancel
	s.mu.Unlock()

	go s.streamer.Stream("steamcmd", stdout, "")
	go s.streamer.Stream("steamcmd", stderr, "")

	go func() {
		err := cmd.Wait()
		s.mu.Lock()
		s.running = false
		s.cancel = nil
		s.mu.Unlock()
		if err == nil {
			s.streamer.Broadcast("steamcmd", "[STEAMCMD] SUCCESS: "+label+" finished")
		} else {
			s.streamer.Broadcast("steamcmd", "[STEAMCMD] ERROR: "+label+" failed: "+err.Error())
		}
	}()

	return nil
}