#!/bin/bash
#
# Merge an audio asset into the audio track of a video asset
#
# Usage:
#
#    jmergeaudio video-file audio-file out-file [at]
#
# video-file  : input video file
# audio-file  : audio file to insert into video
# out-file    : write output file here
# at          : when (on the video timeline) to start playing the audio
#               If omitted, audio will start when video starts
#
SCRIPT="${0}"
SCRIPT_DIR="$(cd "$(dirname "${SCRIPT}")" && pwd)"
. "${SCRIPT_DIR}"/jvc_common

VIDEO_FILE="${1?no video-file provided}"
AUDIO_FILE="${2?no audio-file provided}"
OUT_FILE="${3?no out-file provided}"
T_START="${4}"

echo "
{
  \"assets\": [
    { \"name\": \"video_file\", \"path\": \"${VIDEO_FILE}\" },
    { \"name\": \"audio_file\", \"path\": \"${AUDIO_FILE}\" }
  ],
  \"operations\": [
    {
      \"operation\": \"merge-audio\",
      \"creates\": {
        \"name\": \"with_audio\",
        \"dest\": \"${OUT_FILE}\"
      },
      \"source\": \"video_file\",
      \"audio\": \"audio_file\"$(if [[ -n "${T_START}" ]] ; then echo ",
      \"at\": \"${T_START}\""; fi)
    }
  ]
}
" | "${SCRIPT_DIR}"/jvc ${JVC_OPTIONS}