import os
import json

from datetime import datetime
from string import Template
from typing import List, Tuple, Iterator, Optional, Mapping

from core.schema import Link, ArchiveResult
from core.config import (
    OUTPUT_DIR,
    TEMPLATES_DIR,
    VERSION,
    GIT_SHA,
    FOOTER_INFO,
    TIMEOUT,
)
from core.util import (
    ts_to_date,
    merge_links,
    urlencode,
    htmlencode,
    urldecode,
    derived_link_info,
    wget_output_path,
    enforce_types,
    TimedProgress,
    copy_and_overwrite,
    atomic_write,
)
from core.parse import parse_links
from core.links import validate_links
from core.logs import (
    log_indexing_process_started,
    log_indexing_started,
    log_indexing_finished,
    log_parsing_started,
    log_parsing_finished,
)

TITLE_LOADING_MSG = 'Not yet archived...'




### Homepage index for all the links

@enforce_types
def write_links_index(links: List[Link], out_dir: str=OUTPUT_DIR, finished: bool=False) -> None:
    """create index.html file for a given list of links"""

    log_indexing_process_started()

    log_indexing_started(out_dir, 'index.json')
    timer = TimedProgress(TIMEOUT * 2, prefix='      ')
    write_json_links_index(links, out_dir=out_dir)
    timer.end()
    log_indexing_finished(out_dir, 'index.json')
    
    log_indexing_started(out_dir, 'index.html')
    timer = TimedProgress(TIMEOUT * 2, prefix='      ')
    write_html_links_index(links, out_dir=out_dir, finished=finished)
    timer.end()
    log_indexing_finished(out_dir, 'index.html')


@enforce_types
def load_links_index(out_dir: str=OUTPUT_DIR, import_path: Optional[str]=None) -> Tuple[List[Link], List[Link]]:
    """parse and load existing index with any new links from import_path merged in"""

    existing_links: List[Link] = []
    if out_dir:
        existing_links = list(parse_json_links_index(out_dir))

    new_links: List[Link] = []
    if import_path:
        # parse and validate the import file
        log_parsing_started(import_path)
        raw_links, parser_name = parse_links(import_path)
        new_links = list(validate_links(raw_links))

    # merge existing links in out_dir and new links
    all_links = list(validate_links(existing_links + new_links))

    if import_path and parser_name:
        num_parsed = len(raw_links)
        num_new_links = len(all_links) - len(existing_links)
        log_parsing_finished(num_parsed, num_new_links, parser_name)

    return all_links, new_links


@enforce_types
def write_json_links_index(links: List[Link], out_dir: str=OUTPUT_DIR) -> None:
    """write the json link index to a given path"""

    assert isinstance(links, List), 'Links must be a list, not a generator.'
    assert isinstance(links[0].history, dict)
    assert isinstance(links[0].sources, list)

    if links[0].history.get('title'):
        assert isinstance(links[0].history['title'][0], ArchiveResult)

    if links[0].sources:
        assert isinstance(links[0].sources[0], str)

    path = os.path.join(out_dir, 'index.json')

    index_json = {
        'info': 'ArchiveBox Index',
        'source': 'https://github.com/pirate/ArchiveBox',
        'docs': 'https://github.com/pirate/ArchiveBox/wiki',
        'version': VERSION,
        'num_links': len(links),
        'updated': datetime.now(),
        'links': links,
    }
    atomic_write(index_json, path)


@enforce_types
def parse_json_links_index(out_dir: str=OUTPUT_DIR) -> Iterator[Link]:
    """parse a archive index json file and return the list of links"""

    index_path = os.path.join(out_dir, 'index.json')
    if os.path.exists(index_path):
        with open(index_path, 'r', encoding='utf-8') as f:
            links = json.load(f)['links']
            for link_json in links:
                yield Link.from_json(link_json)

    return ()


@enforce_types
def write_html_links_index(links: List[Link], out_dir: str=OUTPUT_DIR, finished: bool=False) -> None:
    """write the html link index to a given path"""

    copy_and_overwrite(
        os.path.join(TEMPLATES_DIR, 'static'),
        os.path.join(out_dir, 'static'),
    )

    atomic_write('User-agent: *\nDisallow: /', os.path.join(out_dir, 'robots.txt'))

    with open(os.path.join(TEMPLATES_DIR, 'index.html'), 'r', encoding='utf-8') as f:
        index_html = f.read()

    with open(os.path.join(TEMPLATES_DIR, 'index_row.html'), 'r', encoding='utf-8') as f:
        link_row_html = f.read()

    link_rows = []
    for link in links:
        template_row_vars: Mapping[str, str] = {
            **derived_link_info(link),
            'title': (
                link.title
                or (link.base_url if link.is_archived else TITLE_LOADING_MSG)
            ),
            'tags': (link.tags or '') + (' {}'.format(link.extension) if link.is_static else ''),
            'favicon_url': (
                os.path.join('archive', link.timestamp, 'favicon.ico')
                # if link['is_archived'] else 'data:image/gif;base64,R0lGODlhAQABAAD/ACwAAAAAAQABAAACADs='
            ),
            'archive_url': urlencode(
                wget_output_path(link) or 'index.html'
            ),
        }
        link_rows.append(Template(link_row_html).substitute(**template_row_vars))

    template_vars: Mapping[str, str] = {
        'num_links': str(len(links)),
        'date_updated': datetime.now().strftime('%Y-%m-%d'),
        'time_updated': datetime.now().strftime('%Y-%m-%d %H:%M'),
        'footer_info': FOOTER_INFO,
        'version': VERSION,
        'git_sha': GIT_SHA,
        'rows': '\n'.join(link_rows),
        'status': 'finished' if finished else 'running',
    }
    template_html = Template(index_html).substitute(**template_vars)

    atomic_write(template_html, os.path.join(out_dir, 'index.html'))



@enforce_types
def patch_links_index(link: Link, out_dir: str=OUTPUT_DIR) -> None:
    """hack to in-place update one row's info in the generated index html"""

    title = link.title or link.latest_outputs()['title']
    successful = link.num_outputs

    # Patch JSON index
    json_file_links = parse_json_links_index(out_dir)
    patched_links = []
    for saved_link in json_file_links:
        if saved_link.url == link.url:
            patched_links.append(saved_link.overwrite(
                title=title,
                history=link.history,
                updated=link.updated,
            ))
        else:
            patched_links.append(saved_link)
    
    write_json_links_index(patched_links, out_dir=out_dir)

    # Patch HTML index
    html_path = os.path.join(out_dir, 'index.html')
    html = open(html_path, 'r').read().split('\n')
    for idx, line in enumerate(html):
        if title and ('<span data-title-for="{}"'.format(link.url) in line):
            html[idx] = '<span>{}</span>'.format(title)
        elif successful and ('<span data-number-for="{}"'.format(link.url) in line):
            html[idx] = '<span>{}</span>'.format(successful)
            break

    atomic_write('\n'.join(html), html_path)


### Individual link index

@enforce_types
def write_link_index(link: Link, link_dir: Optional[str]=None) -> None:
    link_dir = link_dir or link.link_dir

    write_json_link_index(link, link_dir)
    write_html_link_index(link, link_dir)


@enforce_types
def write_json_link_index(link: Link, link_dir: Optional[str]=None) -> None:
    """write a json file with some info about the link"""
    
    link_dir = link_dir or link.link_dir
    path = os.path.join(link_dir, 'index.json')

    atomic_write(link._asdict(), path)


@enforce_types
def parse_json_link_index(link_dir: str) -> Optional[Link]:
    """load the json link index from a given directory"""
    existing_index = os.path.join(link_dir, 'index.json')
    if os.path.exists(existing_index):
        with open(existing_index, 'r', encoding='utf-8') as f:
            link_json = json.load(f)
            return Link.from_json(link_json)
    return None


@enforce_types
def load_json_link_index(link: Link, link_dir: Optional[str]=None) -> Link:
    """check for an existing link archive in the given directory, 
       and load+merge it into the given link dict
    """
    link_dir = link_dir or link.link_dir
    existing_link = parse_json_link_index(link_dir)
    if existing_link:
        return merge_links(existing_link, link)
    return link


@enforce_types
def write_html_link_index(link: Link, link_dir: Optional[str]=None) -> None:
    link_dir = link_dir or link.link_dir

    with open(os.path.join(TEMPLATES_DIR, 'link_index.html'), 'r', encoding='utf-8') as f:
        link_html = f.read()

    path = os.path.join(link_dir, 'index.html')

    template_vars: Mapping[str, str] = {
        **derived_link_info(link),
        'title': (
            link.title
            or (link.base_url if link.is_archived else TITLE_LOADING_MSG)
        ),
        'url_str': htmlencode(urldecode(link.base_url)),
        'archive_url': urlencode(
            wget_output_path(link)
            or (link.domain if link.is_archived else 'about:blank')
        ),
        'extension': link.extension or 'html',
        'tags': link.tags or 'untagged',
        'status': 'archived' if link.is_archived else 'not yet archived',
        'status_color': 'success' if link.is_archived else 'danger',
        'oldest_archive_date': ts_to_date(link.oldest_archive_date),
    }

    html_index = Template(link_html).substitute(**template_vars)

    atomic_write(html_index, path)