#!/bin/bash
# encode_all encodes the whole library into specified format
#
ulimit -n "$(ulimit -Hn)"
. env_parallel.bash

function ts() {
  date '+%Y-%m-%d_%H:%M'
}

debug_only=false
# debug_only=true
src_dir="$1"
export output_dir="$2"
if [[ -z "$src_dir" || -z "$output_dir" ]]; then
  printf 'Usage:\nencode_dir <input dir> <output dir>\n' >&2
  exit 1
fi

logdir="${HOME}/encoding_logs"
[[ -d "$logdir" ]] || mkdir "$logdir"
start_ts="$(ts)"
log="${logdir}/${start_ts}_encoding_log"
fixes="${logdir}/${start_ts}_fixes.sh"
temp_dir="$(mktemp -d)"

printf '#!/bin/bash\n# FIXES generated by library_works/encode_all\n\n' > "$fixes"

function encode() {
  src_file_and_path="$1"
  src_file="$(basename "$in_file_path")"
  # file is full original path + filename
  src_dir="$(dirname "$src_file_and_path")"
  file_name="$(basename "$src_file_and_path")"
  final_opus="${output_dir}/$(sed -e 's/\.flac$/.opus/' <<< "$file_name")"

  unset tags
  unset dest_dir

  declare -A tags
  while read -r line; do
    tag_type="$(cut -d= -f1 <<< "$line")"
    tag_type="${tag_type^^}"
    tag_val="$(cut -d= -f2- <<< "$line")"
    # TODO: suggest fixes for lower case tags
    tags["$tag_type"]="$tag_val"
  done < <(metaflac --list --block-type='VORBIS_COMMENT' "$src_file_and_path" | \
           grep 'comment\[' | \
           cut -d: -f2- | \
           sed 's/^ //')

  tag_ensure=( 'TRACKNUMBER' 'TITLE' 'ALBUM' 'ARTIST' 'YEAR')
  for tag_type in "${tag_ensure[@]}"; do
    if [[ -z "${tags["$tag_type"]}" ]]; then
      printf '%s is missing tag: %s\n' "$src_file_and_path" "$tag_type" >> "$log"
      tags["$tag_type"]="missing $tag_type"
    fi
  done

  [[ -d "$output_dir" ]] || mkdir -p "$output_dir"
  tag_flags=(
      '--title' "${tags['TITLE']}"
      '--artist' "${tags['ARTIST']}"
      '--album' "${tags['ALBUM']}"
      '--tracknumber' "${tags['TRACKNUMBER']}"
      '--date' "${tags['DATE']}")
  [[ -n "${tags[DISK]}" ]] && tag_flags+=('--comment' "DISK=${tags['DISK']}")
  tags=''
  for tag in "${tag_flags[@]}"; do
    tags+="$(printf '"%s" ' "$tag")"
  done
  cmd=$(printf 'opusenc --downmix-mono --bitrate 48 --speech --quiet --discard-comments --discard-pictures %s "%s" "%s"\n' "$tags" "$src_file_and_path" "$final_opus")
  printf '%s\n' "$cmd"
  eval $cmd

  if [[ -n "$err" ]]; then
    printf '%s\n' "$err" >> "$log"
  fi
}

echo starting processing
# find "$src_dir" -type f -name '*.flac' | while read line; do encode "${line}"; done
# exit 1
# find "$src_dir" -type f -name '*.flac' | while read line; do encode "$line"; done
# wait
find "$src_dir" -type f -name '*.flac' -print0 | env_parallel -P 0 -0 --bar encode {}
echo done processing

echo deleting any empty directories
# find "$output_dir" -empty -type d -delete