#!/usr/bin/env bash

# Root directory containing subfolders (e.g. mouzaakdung, seoiwuzyun, saamgwokjinji)
BASE_DIR="opus"

# Output file
OUTPUT="metadata.list"

# Constants
SPEAKER="zoengjyutgaai"
LANG="yue"

# 1. FIND all CSV files
mapfile -t CSV_FILES < <(find "$BASE_DIR" -type f -name "metadata.csv")

# 2. COUNT total lines (excluding headers)
TOTAL_LINES=0
for CSV_FILE in "${CSV_FILES[@]}"; do
  # Subtract 1 for the header
  FILE_LINES=$(($(wc -l < "$CSV_FILE") - 1))
  # Make sure to avoid negative in case of an empty file
  if [ "$FILE_LINES" -gt 0 ]; then
    TOTAL_LINES=$((TOTAL_LINES + FILE_LINES))
  fi
done

# Safety check
if [ $TOTAL_LINES -le 0 ]; then
  echo "No data lines found or no CSV files found under $BASE_DIR."
  exit 1
fi

# Truncate or create the output file
> "$OUTPUT"

# 3. PROCESS lines
LINE_COUNT=0  # how many lines processed so far

for CSV_FILE in "${CSV_FILES[@]}"; do

  # Identify subdirectory name
  PARENT_DIR="$(dirname "$CSV_FILE")"
  SUBDIR_NAME="$(basename "$PARENT_DIR")"

  # Skip the CSV header line with tail -n +2
  tail -n +2 "$CSV_FILE" | while IFS=',' read -r id episode_id file_name audio_duration transcription; do
    
    # Increment count
    LINE_COUNT=$((LINE_COUNT + 1))

    # Remove any Windows carriage returns in transcription
    transcription=$(echo "$transcription" | tr -d '\r')

    # Construct output line
    echo "${SPEAKER}/${SUBDIR_NAME}/${file_name}|${SPEAKER}|${LANG}|${transcription}" >> "$OUTPUT"

    # Calculate and print progress
    PERCENT=$(( 100 * LINE_COUNT / TOTAL_LINES ))
    # Use \r to rewrite the same line, and -n to avoid automatic newline
    echo -ne "Processing: $PERCENT% ($LINE_COUNT/$TOTAL_LINES)\r"
  done

done

# After the loop, print a newline to cleanly end the progress line
echo
echo "All metadata has been combined into ${OUTPUT}."