from typing import Dict, Any

class ConfidenceScorer:
    """
    Computes a weighted authenticity and quality score across multiple data sources:
    - YouTube footprint: 40%
    - MusicBrainz catalog: 35%
    - Wikidata entity: 25%
    """
    def __init__(self, yt_weight: float = 0.40, mb_weight: float = 0.35, wd_weight: float = 0.25):
        self.w_yt = yt_weight
        self.w_mb = mb_weight
        self.w_wd = wd_weight

    def calculate_score(
        self,
        yt_metrics: Dict[str, Any],
        mb_result: Dict[str, Any],
        wd_result: Dict[str, Any]
    ) -> Dict[str, Any]:
        # 1. YouTube sub-score (0.0 to 1.0)
        yt_score = 0.0
        if yt_metrics.get("status") in ["live_api", "cached"]:
            subs = yt_metrics.get("subscribers", 0)
            views = yt_metrics.get("lifetime_views", 0)
            vids = yt_metrics.get("video_count", 0)

            # Baseline 0.5 for a verified channel existence
            yt_score = 0.5
            if subs >= 1000:
                yt_score += 0.2
            elif subs > 0:
                yt_score += 0.1

            if views >= 50000:
                yt_score += 0.2
            elif views > 0:
                yt_score += 0.1

            if vids >= 5:
                yt_score += 0.1

        # 2. MusicBrainz sub-score
        mb_score = mb_result.get("confidence", 0.0) if mb_result.get("verified") else 0.0

        # 3. Wikidata sub-score
        wd_score = wd_result.get("confidence", 0.0) if wd_result.get("verified") else 0.0

        # Aggregated composite score
        composite = (yt_score * self.w_yt) + (mb_score * self.w_mb) + (wd_score * self.w_wd)
        composite = round(min(1.0, max(0.0, composite)), 2)

        # Confidence category
        if composite >= 0.75:
            tier = "High"
        elif composite >= 0.45:
            tier = "Medium"
        else:
            tier = "Low / Emerging"

        return {
            "composite_confidence": composite,
            "confidence_tier": tier,
            "sub_scores": {
                "youtube": round(yt_score, 2),
                "musicbrainz": round(mb_score, 2),
                "wikidata": round(wd_score, 2)
            }
        }

if __name__ == "__main__":
    scorer = ConfidenceScorer()
    dummy_yt = {"status": "live_api", "subscribers": 5000, "lifetime_views": 250000, "video_count": 18}
    dummy_mb = {"verified": True, "confidence": 1.0}
    dummy_wd = {"verified": True, "confidence": 1.0}
    print("Test Scorer Output:")
    print(scorer.calculate_score(dummy_yt, dummy_mb, dummy_wd))