from .models import Video
from .tasks import convert_video_to_hls, create_thumbnails, delete_original_video
from django.dispatch import receiver
from django.db.models.signals import post_save, post_delete
import os
import django_rq
import shutil

@receiver(post_save, sender=Video)
def video_post_save(sender, instance, created, **kwargs):
    """
    Signal handler for processing a video after saving:
    - Create thumbnails
    - Convert video to different resolutions (HLS)
    - Delete original video
    """
    if not created:
        return

    if instance.file_path and instance.file_name:
        try:
            create_thumbnails(instance, instance.id)

            queue = django_rq.get_queue("default", autocommit=True)
            resolutions = ["1280x720", "640x360", "1920x1080"]
            for resolution in resolutions:
                queue.enqueue(convert_video_to_hls, instance.file_path.path, resolution, instance.id)

            queue.enqueue(delete_original_video, instance.file_path.path)
        
        except Exception as e:
            print(f"Video ID video processing error {instance.id}: {e}")

@receiver(post_delete, sender=Video)
def auto_delete_file_on_delete(sender, instance, **kwargs):
    """
    Deletes the video and all converted files from the file system,
    when the corresponding `Video` object is deleted.
    """
    main_directory = os.path.dirname(instance.file_path.path)
    parent_directory = os.path.dirname(main_directory)
    model_directory = os.path.join(main_directory, str(instance.id))
    thumbnail_directory = os.path.join(parent_directory, 'thumbnails', str(instance.id))

    delete_directory(model_directory)
    delete_directory(thumbnail_directory)

def delete_directory(directory_path):
    """
    Deletes the specified directory recursively.
    """
    if os.path.exists(directory_path):
        shutil.rmtree(directory_path)
    else:
        print(f"Folder not found: {directory_path}")
        
def delete_converted_files(video_file_path):
    """
    Delete all converted video files related to the original video file.
    """
    resolutions = ["360p", "720p", "1080p"]
    for resolution in resolutions:
        converted_video_path = video_file_path + f'_{resolution}.mp4'
        converted_video_path = remove_first_mp4(converted_video_path)
        if os.path.isfile(converted_video_path):
            os.remove(converted_video_path)

def remove_first_mp4(filename):
    """
    Remove the first .mp4 extension from the filename.
    """
    name_part, ext_part = filename.split('.mp4', 1)
    new_filename = name_part + ext_part
    return new_filename