import os
import subprocess
import re
from PyQt6.QtCore import QThread, pyqtSignal

class VideoDownloader(QThread):
    progress_signal = pyqtSignal(str)
    finished_signal = pyqtSignal(bool, str)

    def __init__(self, url, download_path, bin_dir="bin"):
        super().__init__()
        self.url = url
        self.download_path = download_path
        self.bin_dir = os.path.abspath(bin_dir)

    def run(self):
        ytdlp_exe = os.path.join(self.bin_dir, "yt-dlp.exe")
        ffmpeg_exe = os.path.join(self.bin_dir, "ffmpeg.exe")

        if not os.path.exists(ytdlp_exe):
            self.finished_signal.emit(False, f"No se encontró yt-dlp.exe en: {ytdlp_exe}")
            return

        if not os.path.exists(ffmpeg_exe):
            self.finished_signal.emit(False, f"No se encontró ffmpeg.exe en: {ffmpeg_exe}")
            return

        # Creamos una copia del entorno de sistema y añadimos la carpeta 'bin' al PATH
        # Esto asegura que tanto yt-dlp como subprocess encuentren ffmpeg y ffprobe sin fallar
        env = os.environ.copy()
        env["PATH"] = self.bin_dir + os.pathsep + env.get("PATH", "")

        # Comando idéntico a tu terminal
        command = [
            ytdlp_exe,
            "-f", "bestvideo[ext=mp4]+bestaudio[ext=m4a]/bestvideo+bestaudio",
            "--merge-output-format", "mp4",
            "--ffmpeg-location", self.bin_dir,
            "-P", self.download_path,
            self.url
        ]

        try:
            startupinfo = None
            if os.name == 'nt':
                startupinfo = subprocess.STARTUPINFO()
                startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW

            process = subprocess.Popen(
                command,
                stdout=subprocess.PIPE,
                stderr=subprocess.STDOUT,
                text=True,
                startupinfo=startupinfo,
                env=env,  # Le pasamos el entorno enriquecido con el PATH a bin
                encoding='utf-8',
                errors='replace'
            )

            for line in process.stdout:
                line_str = line.strip()
                if line_str:
                    # Imprime en la consola de Python para poder ver cualquier advertencia de yt-dlp
                    print(line_str)
                    
                    if "[download]" in line_str and "%" in line_str:
                        match = re.search(r'(\d+\.\d+%)', line_str)
                        if match:
                            self.progress_signal.emit(f"Descargando: {match.group(1)}")
                    elif "[Merger]" in line_str or "Merging" in line_str:
                        self.progress_signal.emit("Uniendo vídeo y audio en MP4...")

            process.wait()

            if process.returncode == 0:
                self.finished_signal.emit(True, "¡Vídeo descargado y unido correctamente!")
            else:
                self.finished_signal.emit(False, "Error durante la descarga o la fusión.")

        except Exception as e:
            self.finished_signal.emit(False, f"Error de ejecución: {str(e)}")