"""HTML/URL 文件阅读器，支持多种解析方法。"""

import os
from typing import List, Optional, Tuple

from readers.base import BaseReader
from utils import is_html_file, is_url

from . import cleaner
from . import downloader
from . import trafilatura
from . import domscribe
from . import markitdown
from . import html2text


PARSERS = [
    ("trafilatura", lambda c, t: trafilatura.parse(c)),
    ("domscribe", lambda c, t: domscribe.parse(c)),
    ("MarkItDown", lambda c, t: markitdown.parse(c, t)),
    ("html2text", lambda c, t: html2text.parse(c)),
]


class HtmlReader(BaseReader):
    """HTML/URL 文件阅读器"""

    @property
    def supported_extensions(self) -> List[str]:
        return [".html", ".htm"]

    def supports(self, file_path: str) -> bool:
        return is_url(file_path) or is_html_file(file_path)

    def download_and_parse(self, url: str) -> Tuple[Optional[str], List[str]]:
        """下载 URL 并解析"""
        all_failures = []

        # 下载 HTML
        html_content, download_failures = downloader.download_html(url)
        all_failures.extend(download_failures)

        if html_content is None:
            return None, all_failures

        # 清理 HTML
        html_content = cleaner.clean_html_content(html_content)

        # 解析 HTML
        content, parse_failures = self._parse_html_content(html_content, None)
        all_failures.extend(parse_failures)

        return content, all_failures

    def _parse_html_content(self, html_content: str, temp_file_path: Optional[str]) -> Tuple[Optional[str], List[str]]:
        """解析 HTML 内容"""
        failures = []
        content = None

        for parser_name, parser_func in PARSERS:
            content, error = parser_func(html_content, temp_file_path)
            if content is not None:
                return content, failures
            else:
                failures.append(f"- {parser_name}: {error}")

        return None, failures

    def parse(self, file_path: str) -> Tuple[Optional[str], List[str]]:
        all_failures = []

        if is_url(file_path):
            return self.download_and_parse(file_path)

        # 读取 HTML 文件
        try:
            with open(file_path, 'r', encoding='utf-8') as f:
                html_content = f.read()
        except Exception as e:
            return None, [f"- 读取文件失败: {str(e)}"]

        # 清理 HTML
        html_content = cleaner.clean_html_content(html_content)

        # 解析 HTML
        content, parse_failures = self._parse_html_content(html_content, file_path)
        all_failures.extend(parse_failures)

        return content, all_failures