package download

import (
	"app/shelfly/internal/debridlink"
	"io"
	"log"
	"net/http"
	"os"
	"path/filepath"
	"regexp"
	"sync"
	"time"

	"gorm.io/gorm"
)

type DownloadJob struct {
	ID         string    `gorm:"primaryKey;column:id"`
	Link       string    `gorm:"column:link"`
	Name       string    `gorm:"column:name"`
	Status     string    `gorm:"column:status"`     // waiting, running, done, failed, paused
	PathID     uint      `gorm:"column:path_id"`
	Size       int64     `gorm:"column:size"`
	Host       string    `gorm:"column:host"`
	Progress   int       `gorm:"column:progress"`   // 0–100
	StreamURL  string    `gorm:"column:stream_url"` // <- nouveau champ
	CreatedAt  time.Time `gorm:"autoCreateTime"`
	UpdatedAt  time.Time `gorm:"autoUpdateTime"`
}


var (
	jobs   = make(map[string]*DownloadJob)
	jobsMu sync.Mutex
)

// Enregistre un job en mémoire et en base
func RegisterJobWithDB(job *DownloadJob, db *gorm.DB) error {
	jobsMu.Lock()
	jobs[job.ID] = job
	jobsMu.Unlock()

	log.Printf("[JOB] Enregistré : %s (%s)\n", job.Name, job.ID)
	return db.Create(job).Error
}

// Charge tous les jobs depuis la base en mémoire (au démarrage)
func InitJobsFromDB(db *gorm.DB) error {
	var jobList []DownloadJob
	if err := db.Find(&jobList).Error; err != nil {
		return err
	}

	jobsMu.Lock()
	defer jobsMu.Unlock()

	for _, j := range jobList {
		jobCopy := j
		jobs[j.ID] = &jobCopy
	}
	log.Printf("[JOB] %d jobs rechargés depuis la base\n", len(jobs))
	return nil
}

// Met à jour le status d’un job et le persiste
func UpdateJobStatus(id string, status string, db *gorm.DB) {
	jobsMu.Lock()
	defer jobsMu.Unlock()

	if job, ok := jobs[id]; ok {
		job.Status = status
		job.UpdatedAt = time.Now()
		if db != nil {
			_ = db.Save(job)
		}
	}
}

// Met à jour la progression d’un job et le persiste
func UpdateJobProgress(id string, progress int, db *gorm.DB) {
	jobsMu.Lock()
	defer jobsMu.Unlock()

	if job, ok := jobs[id]; ok {
		job.Progress = progress
		job.UpdatedAt = time.Now()
		if db != nil {
			_ = db.Save(job)
		}
	}
}

// Supprime un job (mémoire uniquement)
func DeleteJob(id string) {
	jobsMu.Lock()
	defer jobsMu.Unlock()

	delete(jobs, id)
}

// Liste tous les jobs
func ListJobs() []*DownloadJob {
	jobsMu.Lock()
	defer jobsMu.Unlock()

	list := make([]*DownloadJob, 0, len(jobs))
	for _, job := range jobs {
		list = append(list, job)
	}
	return list
}
const downloadDir = "./downloads"

func StartDownload(job *DownloadJob, downloadURL string, client *debridlink.Client, db *gorm.DB) {
	UpdateJobStatus(job.ID, "running", db)

	resp, err := http.Get(downloadURL)
	if err != nil {
		log.Printf("[ERROR] Téléchargement échoué : %v\n", err)
		UpdateJobStatus(job.ID, "failed", db)
		return
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		log.Printf("[ERROR] Erreur HTTP : %s\n", resp.Status)
		UpdateJobStatus(job.ID, "failed", db)
		return
	}

	// Créer le fichier de destination
	if err := os.MkdirAll(downloadDir, os.ModePerm); err != nil {
		log.Printf("[ERROR] Création du dossier %s échouée : %v\n", downloadDir, err)
		UpdateJobStatus(job.ID, "failed", db)
		return
	}
	destPath := filepath.Join(downloadDir, sanitizeFileName(job.Name))
	outFile, err := os.Create(destPath)
	if err != nil {
		log.Printf("[ERROR] Impossible de créer le fichier : %v\n", err)
		UpdateJobStatus(job.ID, "failed", db)
		return
	}
	defer outFile.Close()

	// Taille totale
	totalSize := resp.ContentLength
	if totalSize <= 0 && job.Size > 0 {
		totalSize = job.Size
	}

	// Téléchargement avec suivi de progression
	buf := make([]byte, 32*1024) // 32KB
	var downloaded int64
	lastUpdate := time.Now()

	for {
		n, err := resp.Body.Read(buf)
		if n > 0 {
			if _, writeErr := outFile.Write(buf[:n]); writeErr != nil {
				log.Printf("[ERROR] Écriture échouée : %v\n", writeErr)
				UpdateJobStatus(job.ID, "failed", db)
				return
			}
			downloaded += int64(n)
		}
		if err != nil {
			if err == io.EOF {
				break
			}
			log.Printf("[ERROR] Erreur de lecture : %v\n", err)
			UpdateJobStatus(job.ID, "failed", db)
			return
		}

		// Mise à jour de la progression toutes les 500ms
		if time.Since(lastUpdate) > 500*time.Millisecond && totalSize > 0 {
			progress := int((downloaded * 100) / totalSize)
			UpdateJobProgress(job.ID, progress, db)
			lastUpdate = time.Now()
		}
	}

	// 100% si on arrive ici
	UpdateJobProgress(job.ID, 100, db)
	UpdateJobStatus(job.ID, "done", db)
	log.Printf("[OK] Fichier téléchargé : %s\n", destPath)
}
func sanitizeFileName(name string) string {
	re := regexp.MustCompile(`[^\w\-.]`)
	return re.ReplaceAllString(name, "_")
}
//***//