"""基于规则计算文章热度、重要性、重复性分数"""
import logging
import math
from datetime import datetime, timedelta, timezone
from typing import List

from sqlalchemy.orm import Session

from config import settings
from models import EnrichedArticle, Taxonomy
from app.task_progress import update_progress, report_loop_progress
from app.tagger import _count_matches, _normalize

logger = logging.getLogger(__name__)


# 综合分权重：热度 30%，重要性 50%，重复性 20%
COMPOSITE_WEIGHT_HEAT = 0.3
COMPOSITE_WEIGHT_IMPORTANCE = 0.5
COMPOSITE_WEIGHT_DUPLICATION = 0.2


def _build_text(article: EnrichedArticle) -> str:
    """构建用于打分的文本"""
    return " ".join([
        article.title or "",
        article.ai_summary or article.original_summary or "",
        article.content or "",
    ])


def _score_by_rules(article: EnrichedArticle, rules: List[Taxonomy]) -> float:
    """基于规则关键词匹配计算分数，规则权重越大得分越高"""
    text = _build_text(article)
    if not text.strip() or not rules:
        return 0.0

    score = 0.0
    for rule in rules:
        keywords = rule.keywords or []
        hits = _count_matches(text, keywords)
        if hits > 0:
            score += min(hits, 5) * rule.weight * 10

    return min(score, 100.0)


def _freshness_score(article: EnrichedArticle) -> float:
    """根据发布时间计算新鲜度加成"""
    now = datetime.now(timezone.utc)
    published = article.published_at
    if not published:
        return 0.0

    # 数据库中读出的 published_at 可能为 naive，默认按 UTC 处理
    if published.tzinfo is None:
        published = published.replace(tzinfo=timezone.utc)

    hours_old = (now - published).total_seconds() / 3600
    if hours_old < 0:
        hours_old = 0

    # 24 小时内满分 20 分，超过 72 小时降至 0
    if hours_old <= 24:
        return 20.0
    elif hours_old >= 72:
        return 0.0
    else:
        return 20.0 * (1 - (hours_old - 24) / 48)


def compute_heat_score(article: EnrichedArticle, heat_rules: List[Taxonomy]) -> float:
    """热度分：关键词命中 + 新鲜度"""
    base = _score_by_rules(article, heat_rules)
    fresh = _freshness_score(article)
    return min(base + fresh, 100.0)


def compute_importance_score(article: EnrichedArticle, importance_rules: List[Taxonomy]) -> float:
    """重要性分：关键词命中"""
    return _score_by_rules(article, importance_rules)


def compute_duplication_score(duplicate_count: int, max_count: int = 5) -> float:
    """
    重复性分：同一主题在多个源出现次数越多，重复性分越高。
    出现 1 次为 0 分，>= max_count 为 100 分。
    """
    if duplicate_count <= 1:
        return 0.0
    score = (duplicate_count - 1) / (max_count - 1) * 100.0
    return min(score, 100.0)


def compute_composite_score(heat: float, importance: float, duplication: float) -> float:
    """计算综合分"""
    return round(
        heat * COMPOSITE_WEIGHT_HEAT
        + importance * COMPOSITE_WEIGHT_IMPORTANCE
        + duplication * COMPOSITE_WEIGHT_DUPLICATION,
        2,
    )


def score_articles(
    db: Session,
    article_ids: List[int] = None,
    update_duplication: bool = False,
) -> int:
    """
    对文章计算热度/重要性/综合分。
    若 update_duplication=True，则同时根据重复组更新重复性分数。
    返回处理数量。
    """
    heat_rules = db.query(Taxonomy).filter(Taxonomy.kind == "heat_rule").all()
    importance_rules = db.query(Taxonomy).filter(Taxonomy.kind == "importance_rule").all()

    query = db.query(EnrichedArticle)
    if article_ids:
        query = query.filter(EnrichedArticle.id.in_(article_ids))

    articles = query.all()
    update_progress("tag_score_dedup", status="running", stage="计算分数", current=0, total=len(articles))
    count = 0
    for article in articles:
        article.heat_score = compute_heat_score(article, heat_rules)
        article.importance_score = compute_importance_score(article, importance_rules)

        if update_duplication:
            dup_count = 0
            if article.duplicate_group_id:
                group = article.duplicate_group
                if group and group.member_article_ids:
                    # 非代表成员数量才是真正的重复次数
                    dup_count = max(len(group.member_article_ids) - 1, 0)
            article.duplication_score = compute_duplication_score(dup_count)

        article.composite_score = compute_composite_score(
            article.heat_score,
            article.importance_score,
            article.duplication_score,
        )
        count += 1
        if count % 50 == 0:
            db.commit()
        report_loop_progress("tag_score_dedup", count, len(articles), "计算分数")

    db.commit()
    logger.info("打分完成: %d 篇文章", count)
    return count