#!/bin/bash

#merges videos/output_n.mp4 with audios/audio_n.mp3 -> merged/merged_n.mp4
BASE_DIR="/home/madina/projects/short_videos"
VIDEOS_DIR="$BASE_DIR/videos"
AUDIOS_DIR="$BASE_DIR/audios"
OUTPUT_DIR="$BASE_DIR/merged"

mkdir -p "$OUTPUT_DIR"

for video in "$VIDEOS_DIR"/output_*.mp4; do
    num=$(basename "$video" | sed 's/output_\([0-9]*\)\.mp4/\1/')
    audio="$AUDIOS_DIR/output_${num}.mp3"
    output="$OUTPUT_DIR/merged_${num}.mp4"

    if [ ! -f "$audio" ]; then
        echo "WARNING: No audio found for shot $num ($audio); skipped"
        continue
    fi

    if [ -f "$output" ]; then
        echo "Already exists; skipped the shot $num."
        continue
    fi

    echo "Merging shot $num: $video + $audio -> $output"
    ffmpeg -i "$video" -i "$audio" \
        -c:v copy \
        -c:a aac \
        -shortest \
        -y "$output"

    echo "Done: $output"
done