CONFIG_FILE: str = "libconv.ini"
CUE_SHEET_EXTENSION: str = ".cue"

import os
import shutil
import logging
import subprocess
from configparser import ConfigParser
from copy import deepcopy
from pathlib import Path
from typing import List, Optional, Tuple
 
LOGGER = logging.getLogger(__name__)

config = ConfigParser()
config.read(CONFIG_FILE)
source_folder: str = config.get("libconv", "source_folder")
destination_folder: str = config.get("libconv", "destination_folder")
source_file_extensions: List[str] = config.get("libconv", "source_file_extensions").split(",")
destination_extension: str = config.get("libconv", "destination_extension")
ffmpeg_options: str = config.get("libconv", "ffmpeg_options")
ffmpeg_location: str = config.get("libconv", "ffmpeg_location")
folder_icon_extensions: List[str] = config.get("libconv", "folder_icon_extensions").split(",")
overwrite: bool = config.get("libconv", "overwrite_files") == "true"
dry_run: bool = config.get("libconv", "dry_run") != "false"

# ----------------------------------------------------------------- #
# file and folder operations

def copy(src: str, dst: str):
    if (dry_run):
        LOGGER.debug(f"copy {src} to {dst}")
    else:
        shutil.copyfile(src, dst, follow_symlinks=True)

def mkdir(path: str):
    if (dry_run):
        LOGGER.debug(f"mkdir -r {path}")
    else:
        os.makedirs(path, exist_ok=True)

def execute(command: str):
    if (dry_run):
        LOGGER.debug(f"execute: {command}")
    else:
        subprocess.run(command)

# ----------------------------------------------------------------- #
# cue sheet processing

def cue_sheet_processor(path: str):
    dst_folder = prepare_destination(path)
    sheet = get_files_with_ext(path, [CUE_SHEET_EXTENSION])

    if (len(sheet) != 1):
        LOGGER.debug(f"ERR: Expected exactly one but {path} contains {len(sheet)} cue sheets")
        exit(-1)

# ----------------------------------------------------------------- #
# basic "folder contains audio files" processing

def file_processor(path: str):
    dst_folder = prepare_destination(path)
    files = get_files_with_ext(path, source_file_extensions)

    for file in files:
        filename = get_filename(file, path)
        execute(f"{ffmpeg_location} -i {file} {ffmpeg_options} {dst_folder + filename}.{destination_extension}")

# ----------------------------------------------------------------- #
# Iteration over library folders and preparation

def contains_extension(path: str, extensions: List[str]) -> bool:
    for root, dirs, files in os.walk(path):
        for file in files:
            for ext in extensions:
                if file.endswith(ext):
                    return True
    return False

def get_files_with_ext(path: str, extensions: List[str]) -> List[str]:
    files = []
    for root, dirs, files in os.walk(path):
        for file in files:
            for ext in extensions:
                if file.endswith(ext):
                    files.append(os.path.join(root, file))
    return files

def prepare_destination(path: str) -> str:
    images = get_files_with_ext(path, folder_icon_extensions)

    sub_path = path.replace(source_folder, "")
    new_path = destination_folder + sub_path
    mkdir(new_path)

    for img in images:
        img_name = img.replace(path, "")
        new_img_path = new_path + img_name
        copy(img, new_img_path)

    return new_path
        
def get_filename(file: str, path: str) -> str:
    fname = file.replace(path, "")
    for ext in source_file_extensions:
        fname = fname.replace("." + ext, "")
    return fname

def scan_folder(path: str):
    for root, dirs, files in os.walk(path):
        for directory in dirs:
            process_folder(os.path.join(root, directory))

def process_folder(path: str):
    if contains_extension(path, [CUE_SHEET_EXTENSION]):
        cue_sheet_processor(path)
    elif contains_extension(path, source_file_extensions):
        file_processor(path)
    else:
        scan_folder(path)

if __name__ == "__main__":
    process_folder(source_folder)