#! /usr/bin/env python3

import argparse
import pathlib
import json
from typing import Dict, Any


meshviewer_file_name = 'meshviewer.json'
nodelist_file_name = 'nodelist.json'


def _merge_nodelist(output_file_path: pathlib.PosixPath, input_files: list[pathlib.PosixPath]):
    output_content: Dict[str, Any] = {
        'version': '',
        'updated_at': '',
        'nodes': list()
    }
    for input_file in input_files:
        json_content = json.loads(input_file.read_bytes())
        output_content['version'] = json_content['version']
        output_content['updated_at'] = json_content['updated_at']
        output_content['nodes'].extend(json_content['nodes'])

    with open(output_file_path, 'w') as output_file:
        output_file.write(json.dumps(output_content))


def _merge_meshviewer(output_file_path: pathlib.PosixPath, input_files: list[pathlib.PosixPath]):
    output_content: Dict[str, Any] = {
        'timestamp': '',
        'nodes': list()
    }
    for input_file in input_files:
        json_content = json.loads(input_file.read_bytes())
        output_content['timestamp'] = json_content['timestamp']
        output_content['nodes'].extend(json_content['nodes'])

    with open(output_file_path, 'w') as output_file:
        output_file.write(json.dumps(output_content))


def _merge_files(output_dir: pathlib.PosixPath, dirs: list[pathlib.PosixPath]):
    _merge_nodelist(output_dir.joinpath('nodelist.json'),
                    [dir.joinpath('nodelist.json') for dir in dirs if dir.joinpath('nodelist.json').exists()])
    _merge_meshviewer(output_dir.joinpath('meshviewer.json'),
                      [dir.joinpath('meshviewer.json') for dir in dirs if dir.joinpath('meshviewer.json').exists()])


if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='Mergetool for meshviewer JSON files.')
    parser.add_argument('output_dir', type=pathlib.Path, help='Output directory to receive the merged files.')
    parser.add_argument('input_dir', nargs='+', type=pathlib.Path,
                        help='Directory containing meshviewer.json and modelist.json.')

    args = parser.parse_args()
    _merge_files(args.output_dir, args.input_dir)