# coding=utf-8
"""
频率词配置加载模块

负责从配置文件加载频率词规则，支持：
- 普通词组
- 必须词（+前缀）
- 过滤词（!前缀）
- 全局过滤词（[GLOBAL_FILTER] 区域）
- 最大显示数量（@前缀）
"""

import os
from pathlib import Path
from typing import Dict, List, Tuple, Optional


def load_frequency_words(
    frequency_file: Optional[str] = None,
) -> Tuple[List[Dict], List[str], List[str]]:
    """
    加载频率词配置

    配置文件格式说明：
    - 每个词组由空行分隔
    - [GLOBAL_FILTER] 区域定义全局过滤词
    - [WORD_GROUPS] 区域定义词组（默认）

    词组语法：
    - 普通词：直接写入，任意匹配即可
    - +词：必须词，所有必须词都要匹配
    - !词：过滤词，匹配则排除
    - @数字：该词组最多显示的条数

    Args:
        frequency_file: 频率词配置文件路径，默认从环境变量 FREQUENCY_WORDS_PATH 获取或使用 config/frequency_words.txt

    Returns:
        (词组列表, 词组内过滤词, 全局过滤词)

    Raises:
        FileNotFoundError: 频率词文件不存在
    """
    if frequency_file is None:
        frequency_file = os.environ.get(
            "FREQUENCY_WORDS_PATH", "config/frequency_words.txt"
        )

    frequency_path = Path(frequency_file)
    if not frequency_path.exists():
        raise FileNotFoundError(f"频率词文件 {frequency_file} 不存在")

    with open(frequency_path, "r", encoding="utf-8") as f:
        content = f.read()

    word_groups = [group.strip() for group in content.split("\n\n") if group.strip()]

    processed_groups = []
    filter_words = []
    global_filters = []

    # 默认区域（向后兼容）
    current_section = "WORD_GROUPS"

    for group in word_groups:
        lines = [line.strip() for line in group.split("\n") if line.strip()]

        if not lines:
            continue

        # 检查是否为区域标记
        if lines[0].startswith("[") and lines[0].endswith("]"):
            section_name = lines[0][1:-1].upper()
            if section_name in ("GLOBAL_FILTER", "WORD_GROUPS"):
                current_section = section_name
                lines = lines[1:]  # 移除标记行

        # 处理全局过滤区域
        if current_section == "GLOBAL_FILTER":
            # 直接添加所有非空行到全局过滤列表
            for line in lines:
                # 忽略特殊语法前缀，只提取纯文本
                if line.startswith(("!", "+", "@")):
                    continue  # 全局过滤区不支持特殊语法
                if line:
                    global_filters.append(line)
            continue

        # 处理词组区域
        words = lines

        group_required_words = []
        group_normal_words = []
        group_filter_words = []
        group_max_count = 0  # 默认不限制

        for word in words:
            if word.startswith("@"):
                # 解析最大显示数量（只接受正整数）
                try:
                    count = int(word[1:])
                    if count > 0:
                        group_max_count = count
                except (ValueError, IndexError):
                    pass  # 忽略无效的@数字格式
            elif word.startswith("!"):
                filter_words.append(word[1:])
                group_filter_words.append(word[1:])
            elif word.startswith("+"):
                group_required_words.append(word[1:])
            else:
                group_normal_words.append(word)

        if group_required_words or group_normal_words:
            if group_normal_words:
                group_key = " ".join(group_normal_words)
            else:
                group_key = " ".join(group_required_words)

            processed_groups.append(
                {
                    "required": group_required_words,
                    "normal": group_normal_words,
                    "group_key": group_key,
                    "max_count": group_max_count,
                }
            )

    return processed_groups, filter_words, global_filters


def matches_word_groups(
    title: str,
    word_groups: List[Dict],
    filter_words: List[str],
    global_filters: Optional[List[str]] = None
) -> bool:
    """
    检查标题是否匹配词组规则

    Args:
        title: 标题文本
        word_groups: 词组列表
        filter_words: 过滤词列表
        global_filters: 全局过滤词列表

    Returns:
        是否匹配
    """
    # 防御性类型检查：确保 title 是有效字符串
    if not isinstance(title, str):
        title = str(title) if title is not None else ""
    if not title.strip():
        return False

    title_lower = title.lower()

    # 全局过滤检查（优先级最高）
    if global_filters:
        if any(global_word.lower() in title_lower for global_word in global_filters):
            return False

    # 如果没有配置词组，则匹配所有标题（支持显示全部新闻）
    if not word_groups:
        return True

    # 过滤词检查
    if any(filter_word.lower() in title_lower for filter_word in filter_words):
        return False

    # 词组匹配检查
    for group in word_groups:
        required_words = group["required"]
        normal_words = group["normal"]

        # 必须词检查
        if required_words:
            all_required_present = all(
                req_word.lower() in title_lower for req_word in required_words
            )
            if not all_required_present:
                continue

        # 普通词检查
        if normal_words:
            any_normal_present = any(
                normal_word.lower() in title_lower for normal_word in normal_words
            )
            if not any_normal_present:
                continue

        return True

    return False