added script

scripts/flac2mp3.sh

@@ -0,0 +1,129 @@
+#!/bin/bash
+
+# --- Script Configuration for Robustness ---
+set -euo pipefail # Exit on error, unset variables, and pipe failures
+# set -x # Uncomment this line for debugging output (prints commands as they are executed)
+
+# --- FLAC to MP3 Converter (Bash Script) ---
+#
+# This script converts all FLAC files found in a specified input directory
+# and its subdirectories into MP3 files, saving them to a specified output directory
+# while preserving the original directory structure.
+#
+# Usage: ./convert_flac_to_mp3.sh <input_directory> <output_directory>
+#
+# Arguments:
+#   <input_directory>  : The path to the directory containing FLAC files.
+#   <output_directory> : The path where the converted MP3 files will be saved.
+#
+# Requirements:
+#   - ffmpeg: Must be installed and accessible in your system's PATH.
+#   - realpath: Must be installed and accessible in your system's PATH.
+#               (Typically part of GNU coreutils on Linux. macOS users might need `brew install coreutils`)
+#   - xargs: Standard utility, usually present.
+#
+# Example:
+#   ./convert_flac_to_mp3.sh "/home/user/music/flac albums" "/home/user/music/mp3 converted"
+#
+
+# Check if ffmpeg is installed
+if ! command -v ffmpeg &> /dev/null; then
+    echo "Error: ffmpeg is not installed. Please install it to use this script."
+    exit 1
+fi
+
+# Check if realpath is installed
+if ! command -v realpath &> /dev/null; then
+    echo "Error: realpath command not found. This script requires 'realpath' for robust path handling."
+    echo "Please install it (e.g., 'sudo apt-get install realpath' on Debian/Ubuntu, or 'brew install coreutils' on macOS)."
+    exit 1
+fi
+
+# Check if xargs is installed (should be standard, but good practice)
+if ! command -v xargs &> /dev/null; then
+    echo "Error: xargs command not found. This script requires 'xargs'."
+    echo "Please ensure xargs is installed on your system."
+    exit 1
+fi
+
+# Check for correct number of arguments
+if [ "$#" -ne 2 ]; then
+    echo "Usage: $0 <input_directory> <output_directory>"
+    echo "Example: $0 /path/to/flac_files /path/to/mp3_output"
+    exit 1
+fi
+
+# Resolve input and output directories to their absolute, canonical paths.
+# This makes path handling consistent and robust against symbolic links or relative paths.
+# Export them so they are available in the subshell created by 'xargs'.
+export INPUT_DIR=$(realpath "$1")
+export OUTPUT_DIR=$(realpath "$2")
+
+# Check if resolved input directory exists
+if [ ! -d "$INPUT_DIR" ]; then
+    echo "Error: Input directory '$INPUT_DIR' does not exist or is not a directory."
+    exit 1
+fi
+
+# Create the output directory if it doesn't exist.
+# mkdir -p handles creation of parent directories and doesn't error if it already exists.
+mkdir -p "$OUTPUT_DIR"
+
+echo "Starting FLAC to MP3 conversion..."
+echo "Input Directory (resolved): $INPUT_DIR"
+echo "Output Directory (resolved): $OUTPUT_DIR"
+echo "--------------------------------------------------"
+
+# Define a function to process a single FLAC file.
+# This function will be called by 'xargs' for each file found.
+convert_single_file() {
+    local FLAC_FILEPATH="$1" # The input FLAC file path passed by xargs
+
+    # Ensure FLAC_FILEPATH is an absolute and canonical path.
+    FLAC_FILEPATH_CANONICAL=$(realpath "$FLAC_FILEPATH")
+
+    # Calculate the relative path of the FLAC file from the input directory.
+    # realpath --relative-to is the most robust way to get this.
+    RELATIVE_PATH=$(realpath --relative-to="$INPUT_DIR" "$FLAC_FILEPATH_CANONICAL")
+
+    # Construct the output filename by replacing the .flac extension with .mp3.
+    MP3_FILENAME="${RELATIVE_PATH%.flac}.mp3"
+
+    # Construct the full output path by combining the resolved output directory
+    # with the newly calculated relative MP3 filename.
+    INPUT_BASENAME=$(basename "$INPUT_DIR")
+    OUTPUT_FILEPATH="${OUTPUT_DIR}/${INPUT_BASENAME}/${MP3_FILENAME}"
+
+    # Create the necessary subdirectory structure in the output directory.
+    mkdir -p "$(dirname "$OUTPUT_FILEPATH")"
+
+    echo "Converting: '$FLAC_FILEPATH_CANONICAL'"
+    echo "Saving to:  '$OUTPUT_FILEPATH'"
+
+    # Execute the ffmpeg command for conversion.
+    # We suppress output to keep the main script clean, but errors will still be reported by 'set -euo pipefail'.
+    ffmpeg -i "$FLAC_FILEPATH_CANONICAL" -map 0:a:0 -codec:a libmp3lame -b:a 320k -y "$OUTPUT_FILEPATH" >/dev/null 2>&1
+
+    # Check the exit status of the ffmpeg command.
+    if [ $? -eq 0 ]; then
+        echo "Successfully converted: '$MP3_FILENAME'"
+    else
+        # If ffmpeg fails, print a more specific error message.
+        # Note: 'set -e' will cause the script to exit on the first ffmpeg failure.
+        echo "Error converting: '$FLAC_FILEPATH_CANONICAL'. Check ffmpeg output for details (remove >/dev/null 2>&1 to see)."
+    fi
+    echo "--------------------------------------------------"
+}
+
+# Export the function so xargs can find it.
+export -f convert_single_file
+export INPUT_DIR
+export OUTPUT_DIR
+
+# Find all .flac files recursively starting from the resolved input directory.
+# Pipe the null-delimited list of files to 'xargs -0', which then executes
+# the 'bash -c' command (which calls our defined function) for each file.
+find "$INPUT_DIR" -type f -name "*.flac" -print0 | sort -zV | xargs -0 -I {} bash -c 'convert_single_file "$@"' _ {}
+
+echo "Conversion process completed."
+