#!/usr/bin/env python3

from dataclasses import dataclass, field
import inspect
import os
import re
import sys
from typing import List

def log(message):
    open('log.txt', 'a').write('{}: {}\n'.format(inspect.currentframe().f_back.f_lineno, message))

def log_flush():
    open('log.txt', 'w').write('')

# TODO: Use regex, something like : list(filter(re.compile(FILE_EXCLUDE).match, ['phabricator.schema.json']))
FILE_EXCLUDE = ['.DS_Store', '.mypy_cache', 'index.md', 'img', 'aws_codecommit.schema.json', 'other_external_service.schema.json', 'bitbucket_server.schema.json', 'phabricator.schema.json', 'gitolite.schema.json', 'github.schema.json', 'gitlab.schema.json', 'critical.schema.json', 'site.schema.json']
DIR_EXCLUDE = ['_resources']

class NoPageTitleError(Exception):
    pass

SECTION_TEMPLATE = '''<ul class="content-nav-section expandable" data-nav-section="{section}">
  <button class="content-nav-button"></button>
  <div class="close--icon">
    <svg class="mdi-icon material-icons" width="24" height="24" fill="#000" viewBox="0 0 24 24">
        <path d="M19,6.41L17.59,5L12,10.59L6.41,5L5,6.41L10.59,12L5,17.59L6.41,19L12,13.41L17.59,19L19,17.59L13.41,12L19,6.41Z"></path>
    </svg>
  </div>
  <li class="content-nav-no-hover">
    <a class="content-nav-section-header" href="/{section}">{section_title}</a>
    <ul class="content-nav-section-group">
        {section_group_items}
    </ul>
  </li>
</ul>'''

SECTION_GROUP_ITEM_TEMPLATE = '''<li><a href="{section_group_item_url}">{section_group_item_title}</a></li>
<li class="content-nav-no-hover">
    <ul class="content-nav-section-subsection">
        {section_group_items}
    </ul>
</li>'''

SUB_SECTION_TEMPLATE = '''<li><a href="{section_group_subsection_item_url}">{section_group_subsection_item_title}</a></li>
<li class="content-nav-no-hover" data-sub-section-item="{section_group_subsection_item_title}")>
    <ul>
        {section_group_subsection_items}
    </ul>
</li>'''

@dataclass
class MenuItem:
    title: str
    content: str

@dataclass
class MenuItems:
    items:List[MenuItem] = field(default_factory=list)

    def add(self, item:MenuItem):
        if type(item) == str:
            raise Exception

        self.items.append(item)

    def sorted(self) -> List[MenuItem]:
        return sorted(self.items, key=lambda menu_item: menu_item.title)

    @property
    def count(self) -> int:
        return len(self.items)
    @property
    def contents(self) -> List[str]:
        return [item.content for item in self.sorted()]

def get_sections():
    sections = MenuItems()

    for section in os.listdir('./'):
        if not os.path.isdir(section) or section in DIR_EXCLUDE:
            continue

        section_title = get_title('{}/index.md'.format(section))

        sections.add(
            MenuItem(
                title=section_title,
                content=SECTION_TEMPLATE.format(
                    section=section,
                    section_title=section_title,
                    section_group_items=get_section_items(section).content
                )
            )
        )

    return '\n'.join(sections.contents)

def get_section_items(section):
    section_items = sections = MenuItems()
    section_title = get_title('{}/index.md'.format(section))

    for section_item in os.listdir(section):
        if section_item in FILE_EXCLUDE or section_item in DIR_EXCLUDE:
            continue

        section_item_file_path = '{}/{}'.format(section, section_item)

        if os.path.isdir(section_item_file_path):
            section_items.add(
                get_section_group_item(section, section_item, section_item_file_path)
            )
            continue

        title = get_title(section_item_file_path)
        section_items.add(
            MenuItem(
                title=title,
                content=make_menu_item(file_path_to_url(section_item_file_path), title)
            )
        )

    return MenuItem(
        title=section_title,
        content='\n'.join(section_items.contents)
    )

def get_section_group_item(section, section_item, url) -> str:
    section_group_items = MenuItems()

    section_group_item_file_path = '{}/{}'.format(section, section_item, section_item)
    section_group_item_title = get_title('{}/index.md'.format(section_group_item_file_path))
    section_group_item_url = file_path_to_url(section_group_item_file_path)

    for section_group_item_child in os.listdir('{}/{}'.format(section, section_item)):
        if section_group_item_child in FILE_EXCLUDE:
            continue

        section_group_item_child_path = '{}/{}/{}'.format(section, section_item, section_group_item_child)
        section_group_item_child_url = file_path_to_url(section_group_item_child_path)

        if os.path.isdir(section_group_item_child_path):
            section_group_items.add(
                get_section_group_subsection_item(section, section_item, section_group_item_child)
            )
            continue

        else:
            section_group_item_child_title = get_title(section_group_item_child_path)
            section_group_items.add(
                MenuItem(
                    title=section_group_item_child_title,
                    content=make_menu_item(section_group_item_child_url, section_group_item_child_title)
                )
            )

    if section_group_items.count <= 1:
        return MenuItem(
            title=section_group_item_title,
            content=make_menu_item(section_group_item_url, section_group_item_title)
        )

    return MenuItem(
        title=section_group_item_title,
        content=SECTION_GROUP_ITEM_TEMPLATE.format(
            section_group_item_title=section_group_item_title,
            section_group_item_url=section_group_item_url,
            section_group_items='\n'.join(section_group_items.contents)
        )
    )

def get_section_group_subsection_item(section, section_item, section_group_item_child) -> str:
    section_group_subsection_items = MenuItems()

    section_group_subsection_item_file_path = '{}/{}/{}'.format(section, section_item, section_group_item_child)
    section_group_subsection_item_title = get_title('{}/index.md'.format(section_group_subsection_item_file_path))
    section_group_subsection_item_url = file_path_to_url(section_group_subsection_item_file_path)

    for section_group_subsection_item_child in os.listdir('{}/{}/{}'.format(section, section_item, section_group_item_child)):
        section_group_subsection_item_child_path = '{}/{}/{}/{}'.format(section, section_item, section_group_item_child, section_group_subsection_item_child)
        section_group_subsection_item_child_url = file_path_to_url(section_group_subsection_item_child_path)

        if section_group_subsection_item_child in FILE_EXCLUDE or os.path.isdir(section_group_subsection_item_child_path):
            continue

        section_group_subsection_item_child_title = get_title(section_group_subsection_item_child_path)

        section_group_subsection_items.add(
            MenuItem(
                title=section_group_subsection_item_child_title,
                content=make_menu_item(section_group_subsection_item_child_url, get_title(section_group_subsection_item_child_path))
            )
        )

    return MenuItem(
        title=section_group_subsection_item_title,
        content=SUB_SECTION_TEMPLATE.format(
            section_group_subsection_item_url=section_group_subsection_item_url,
            section_group_subsection_item_title=section_group_subsection_item_title,
            section_group_subsection_items='\n'.join(section_group_subsection_items.contents)
    ))

def make_menu_item(url:str, text:str) -> str:
    return '<li><a href="{}">{}</a></li>'.format(url, text)

def get_title(file_path:str) -> str:
    for line in open(file_path).read().split('\n'):
        try:
            return re.search('^# (.*)$', line).groups()[0]
        except Exception:
            continue

    raise NoPageTitleError('No page title found for file {}'.format(file_path))

def file_path_to_url(file_path):
    return '/{}'.format(file_path.replace('.md', ''))

if __name__ == '__main__':
    log_flush()
    sys.stdout.write(get_sections())