#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import argparse
import os
import sys
from pathlib import Path

script_path = Path(__file__).absolute()

sys.path.insert(0, str(script_path.parent.parent))  # to find wireviz module
from wv_helper import open_file_append, open_file_read, open_file_write

from wireviz import APP_NAME, __version__, wireviz

dir = script_path.parent.parent.parent
readme = 'readme.md'
groups = {
    'examples': {
        'path': dir / 'examples',
        'prefix': 'ex',
        readme: [], # Include no files
        'title': 'Example Gallery',
    },
    'tutorial' : {
        'path': dir / 'tutorial',
        'prefix': 'tutorial',
        readme: ['md', 'yml'], # Include .md and .yml files
        'title': f'{APP_NAME} Tutorial',
    },
    'demos' : {
        'path': dir / 'examples',
        'prefix': 'demo',
    },
}

input_extensions = ['.yml']
extensions_not_containing_graphviz_output = ['.gv', '.bom.tsv']
extensions_containing_graphviz_output = ['.png', '.svg', '.html']
generated_extensions = extensions_not_containing_graphviz_output + extensions_containing_graphviz_output


def collect_filenames(description, groupkey, ext_list):
    path = groups[groupkey]['path']
    patterns = [f"{groups[groupkey]['prefix']}*{ext}" for ext in ext_list]
    if ext_list != input_extensions and readme in groups[groupkey]:
        patterns.append(readme)
    print(f'{description} {groupkey} in "{path}"')
    return sorted([filename for pattern in patterns for filename in path.glob(pattern)])


def build_generated(groupkeys):
    for key in groupkeys:
        # preparation
        path = groups[key]['path']
        build_readme = readme in groups[key]
        if build_readme:
            include_readme = 'md' in groups[key][readme]
            include_source = 'yml' in groups[key][readme]
            with open_file_write(path / readme) as out:
                out.write(f'# {groups[key]["title"]}\n\n')
        # collect and iterate input YAML files
        for yaml_file in collect_filenames('Building', key, input_extensions):
            print(f'  "{yaml_file}"')
            wireviz.parse_file(yaml_file)

            if build_readme:
                i = ''.join(filter(str.isdigit, yaml_file.stem))

                with open_file_append(path / readme) as out:
                    if include_readme:
                        with open_file_read(yaml_file.with_suffix('.md')) as info:
                            for line in info:
                                out.write(line.replace('## ', f'## {i} - '))
                            out.write('\n\n')
                    else:
                        out.write(f'## Example {i}\n')

                    if include_source:
                        with open_file_read(yaml_file) as src:
                            out.write('```yaml\n')
                            for line in src:
                                out.write(line)
                            out.write('```\n')
                        out.write('\n')

                    out.write(f'![]({yaml_file.stem}.png)\n\n')
                    out.write(f'[Source]({yaml_file.name}) - [Bill of Materials]({yaml_file.stem}.bom.tsv)\n\n\n')


def clean_generated(groupkeys):
    for key in groupkeys:
        # collect and remove files
        for filename in collect_filenames('Cleaning', key, generated_extensions):
            if filename.is_file():
                print(f'  rm "{filename}"')
                Path(filename).unlink()


def compare_generated(groupkeys, branch = '', include_graphviz_output = False):
    if branch:
        branch = f' {branch.strip()}'
    compare_extensions = generated_extensions if include_graphviz_output else extensions_not_containing_graphviz_output
    for key in groupkeys:
        # collect and compare files
        for filename in collect_filenames('Comparing', key, compare_extensions):
            cmd = f'git --no-pager diff{branch} -- "{filename}"'
            print(f'  {cmd}')
            os.system(cmd)


def restore_generated(groupkeys, branch = ''):
    if branch:
        branch = f' {branch.strip()}'
    for key in groupkeys:
        # collect input YAML files
        filename_list = collect_filenames('Restoring', key, input_extensions)
        # collect files to restore
        filename_list = [fn.with_suffix(ext) for fn in filename_list for ext in generated_extensions]
        if readme in groups[key]:
            filename_list.append(groups[key]['path'] / readme)
        # restore files
        for filename in filename_list:
            cmd = f'git checkout{branch} -- "{filename}"'
            print(f'  {cmd}')
            os.system(cmd)


def parse_args():
    parser = argparse.ArgumentParser(description=f'{APP_NAME} Example Manager',)
    parser.add_argument('-V', '--version', action='version', version=f'%(prog)s - {APP_NAME} {__version__}')
    parser.add_argument('action', nargs='?', action='store',
                        choices=['build','clean','compare','diff','restore'], default='build',
                        help='what to do with the generated files (default: build)')
    parser.add_argument('-c', '--compare-graphviz-output', action='store_true',
                        help='the Graphviz output is also compared (default: False)')
    parser.add_argument('-b', '--branch', action='store', default='',
                        help='branch or commit to compare with or restore from')
    parser.add_argument('-g', '--groups', nargs='+',
                        choices=groups.keys(), default=groups.keys(),
                        help='the groups of generated files (default: all)')
    return parser.parse_args()


def main():
    args = parse_args()
    if args.action == 'build':
        build_generated(args.groups)
    elif args.action == 'clean':
        clean_generated(args.groups)
    elif args.action == 'compare' or args.action == 'diff':
        compare_generated(args.groups, args.branch, args.compare_graphviz_output)
    elif args.action == 'restore':
        restore_generated(args.groups, args.branch)


if __name__ == '__main__':
    main()