package main

import (
    "fmt"
    "io"
    "log"
    "net/http"
    "strings"
    "time"
)

func main() {
    // Handler untuk proxy video
    http.HandleFunc("/proxy", proxyHandler)
    
    // Serve HTML generator
    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        http.ServeFile(w, r, "index.html")
    })

    log.Println("🚀 Server running on :7860")
    log.Println("📡 Proxy endpoint: http://localhost:7860/proxy")
    log.Println("🌐 CORS enabled for all origins")
    log.Fatal(http.ListenAndServe(":7860", nil))
}

func proxyHandler(w http.ResponseWriter, r *http.Request) {
    // ============ CORS HEADERS ============
    // Allow all origins untuk remote upload
    w.Header().Set("Access-Control-Allow-Origin", "*")
    w.Header().Set("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS, HEAD")
    w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization, accept, origin, Cache-Control, X-Requested-With, Range")
    w.Header().Set("Access-Control-Expose-Headers", "Content-Length, Content-Range, Content-Disposition, Accept-Ranges")
    w.Header().Set("Access-Control-Allow-Credentials", "true")
    w.Header().Set("Access-Control-Max-Age", "86400") // 24 jam cache preflight
    
    // Handle preflight OPTIONS request
    if r.Method == "OPTIONS" {
        w.WriteHeader(http.StatusOK)
        return
    }

    // ============ PARSE PARAMETERS ============
    query := r.URL.Query()
    videoParam := query.Get("video")
    exp := query.Get("exp")
    sig := query.Get("sig")
    videoType := query.Get("type") // "mp4" atau "null"
    domain := query.Get("d")       // domain CDN, misal: cdn.xvdhsy.pro

    if videoParam == "" || exp == "" || sig == "" || domain == "" {
        http.Error(w, "Missing parameters: video, exp, sig, d required", http.StatusBadRequest)
        return
    }

    // ============ REKONSTRUKSI URL ============
    // Hapus .mp4 dari video parameter
    videoId := strings.TrimSuffix(videoParam, ".mp4")
    
    // Pastikan domain tidak memiliki protocol
    domain = strings.TrimPrefix(domain, "http://")
    domain = strings.TrimPrefix(domain, "https://")
    domain = strings.TrimSuffix(domain, "/")
    
    // Rekonstruksi URL asli
    // Format: https://{domain}/{videoId}?exp={exp}&sig={sig}
    originalURL := fmt.Sprintf("https://%s/%s?exp=%s&sig=%s", domain, videoId, exp, sig)

    log.Printf("📥 Proxy request: %s -> %s", r.URL.String(), originalURL)

    // ============ BUAT REQUEST ============
    client := &http.Client{
        Timeout: 120 * time.Second, // Timeout lebih lama untuk video besar
    }

    req, err := http.NewRequest("GET", originalURL, nil)
    if err != nil {
        http.Error(w, "Failed to create request", http.StatusInternalServerError)
        return
    }

    // Set headers untuk request ke CDN
    req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36")
    req.Header.Set("Accept", "*/*")
    req.Header.Set("Accept-Encoding", "gzip, deflate, br")
    req.Header.Set("Accept-Language", "en-US,en;q=0.9")
    req.Header.Set("Connection", "keep-alive")
    req.Header.Set("Sec-Fetch-Dest", "video")
    req.Header.Set("Sec-Fetch-Mode", "cors")
    req.Header.Set("Sec-Fetch-Site", "cross-site")
    
    // Copy Range header untuk support streaming
    if rangeHeader := r.Header.Get("Range"); rangeHeader != "" {
        req.Header.Set("Range", rangeHeader)
        log.Printf("📊 Range request: %s", rangeHeader)
    }

    // ============ EKSEKUSI REQUEST ============
    resp, err := client.Do(req)
    if err != nil {
        log.Printf("❌ Error fetching video: %v", err)
        http.Error(w, "Failed to fetch video", http.StatusInternalServerError)
        return
    }
    defer resp.Body.Close()

    log.Printf("✅ Response status: %s, Content-Length: %s", resp.Status, resp.Header.Get("Content-Length"))

    // ============ SET RESPONSE HEADERS ============
    // CORS headers (already set above)
    
    // Content Type untuk video
    contentType := resp.Header.Get("Content-Type")
    if contentType == "" || !strings.Contains(contentType, "video") {
        contentType = "video/mp4"
    }
    w.Header().Set("Content-Type", contentType)
    
    // Support range requests (streaming & seeking)
    w.Header().Set("Accept-Ranges", "bytes")
    
    // Copy Content-Length jika ada
    if resp.Header.Get("Content-Length") != "" {
        w.Header().Set("Content-Length", resp.Header.Get("Content-Length"))
    }
    
    // Set Content-Disposition berdasarkan parameter type
    filename := videoId
    if videoType == "mp4" {
        filename = videoId + ".mp4"
    }
    // Gunakan attachment agar bisa di-download oleh remote upload
    w.Header().Set("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s\"", filename))
    
    // Cache control untuk performance
    w.Header().Set("Cache-Control", "public, max-age=86400")
    
    // Support untuk Doodstream & platform sejenis
    w.Header().Set("X-Content-Type-Options", "nosniff")
    w.Header().Set("X-Frame-Options", "SAMEORIGIN")
    
    // ============ KIRIM RESPONSE ============
    // Copy status code
    w.WriteHeader(resp.StatusCode)
    
    // Copy body dengan buffering untuk performance
    buffer := make([]byte, 32*1024) // 32KB buffer
    io.CopyBuffer(w, resp.Body, buffer)
    
    log.Printf("✅ Stream completed for: %s", videoId)
}