"""
Team Predictor Engine - V20 Ensemble Component
Combines ELO ratings, form stats, H2H records and team statistics.

Weight: 30% in ensemble
"""

import os
import sys
from typing import Dict, Optional, Tuple, Any
from dataclasses import dataclass, field

# Add parent to path
sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__)))))

from features.elo_system import get_elo_system
from features.h2h_engine import get_h2h_engine
from features.momentum_engine import get_momentum_engine, MomentumData
from features.team_stats_engine import get_team_stats_engine


@dataclass
class TeamPrediction:
    """Team engine prediction output."""
    home_win_prob: float = 0.33
    draw_prob: float = 0.33
    away_win_prob: float = 0.33
    home_xg: float = 1.3
    away_xg: float = 1.1
    form_advantage: float = 0.0  # -1 to +1, positive = home advantage
    h2h_advantage: float = 0.0   # -1 to +1
    elo_diff: float = 0.0
    confidence: float = 0.0
    
    def to_dict(self) -> dict:
        return {
            "home_win_prob": round(self.home_win_prob * 100, 1),
            "draw_prob": round(self.draw_prob * 100, 1),
            "away_win_prob": round(self.away_win_prob * 100, 1),
            "home_xg": round(self.home_xg, 2),
            "away_xg": round(self.away_xg, 2),
            "form_advantage": round(self.form_advantage, 2),
            "h2h_advantage": round(self.h2h_advantage, 2),
            "elo_diff": round(self.elo_diff, 0),
            "confidence": round(self.confidence, 1)
        }
    
    raw_features: Dict[str, Any] = field(default_factory=dict)


class TeamPredictorEngine:
    """
    Team-based prediction engine.
    
    Uses:
    - ELO Rating System (venue-adjusted, league-weighted)
    - H2H Engine (head-to-head history)
    - Momentum Engine (recent form)
    - Team Stats Engine (possession, shots, corners)
    """
    
    def __init__(self):
        self.elo_system = get_elo_system()
        self.h2h_engine = get_h2h_engine()
        self.momentum_engine = get_momentum_engine()
        self.team_stats_engine = get_team_stats_engine()
        
        print("✅ TeamPredictorEngine initialized")
    
    def predict(self, 
                home_team_id: str, 
                away_team_id: str,
                match_date_ms: int,
                home_team_name: str = "",
                away_team_name: str = "") -> TeamPrediction:
        """
        Generate team-based prediction.
        
        Args:
            home_team_id: Home team ID
            away_team_id: Away team ID  
            match_date_ms: Match date in milliseconds
            home_team_name: Home team name (for ELO)
            away_team_name: Away team name (for ELO)
            
        Returns:
            TeamPrediction with 1X2 probabilities and xG
        """
        
        # 1. Get ELO predictions
        elo_pred = self.elo_system.predict_match(home_team_id, away_team_id)
        elo_features = self.elo_system.get_match_features(home_team_id, away_team_id)
        
        # 2. Get H2H features
        try:
            h2h_features = self.h2h_engine.get_features(
                home_team_id, away_team_id, match_date_ms
            )
        except Exception:
            h2h_features = {
                "h2h_home_win_rate": 0.5,
                "h2h_away_win_rate": 0.5,
                "h2h_avg_goals": 2.5,
                "h2h_btts_rate": 0.5
            }
        
        # 3. Get Momentum/Form features
        try:
            # key: form_score should be 0-1 derived from momentum_score (-1 to 1)
            home_mom_data = self.momentum_engine.calculate_momentum(home_team_id, match_date_ms)
            away_mom_data = self.momentum_engine.calculate_momentum(away_team_id, match_date_ms)
            
            home_form_score = (home_mom_data.momentum_score + 1) / 2
            away_form_score = (away_mom_data.momentum_score + 1) / 2
        except Exception as e:
            print(f"⚠️ MomentumEngine error: {e}")
            home_mom_data = MomentumData()
            away_mom_data = MomentumData()
            home_form_score = 0.5
            away_form_score = 0.5
        
        # 4. Get Team Stats
        home_stats = self.team_stats_engine.get_features(home_team_id, match_date_ms)
        away_stats = self.team_stats_engine.get_features(away_team_id, match_date_ms)
        
        # 5. Combine predictions
        # ELO-based 1X2 (60% weight)
        elo_home = elo_pred.get("home_win_prob", 0.33)
        elo_draw = elo_pred.get("draw_prob", 0.33)
        elo_away = elo_pred.get("away_win_prob", 0.33)
        
        # Adjust based on H2H (20% weight)
        h2h_home_rate = h2h_features.get("h2h_home_win_rate", 0.5)
        h2h_away_rate = h2h_features.get("h2h_away_win_rate", 0.5)
        
        # Adjust based on form (20% weight)
        home_form = home_form_score
        away_form = away_form_score
        form_diff = (home_form - away_form)  # -1 to +1
        
        # Weighted combination
        final_home = elo_home * 0.6 + h2h_home_rate * 0.2 + (0.5 + form_diff * 0.3) * 0.2
        final_away = elo_away * 0.6 + h2h_away_rate * 0.2 + (0.5 - form_diff * 0.3) * 0.2
        final_draw = 1.0 - final_home - final_away
        
        # Normalize
        total = final_home + final_draw + final_away
        if total > 0:
            final_home /= total
            final_draw /= total
            final_away /= total
        
        # Calculate xG based on stats and form (conservative base)
        home_conversion = home_stats.get("shot_conversion_rate", 0.1)
        away_conversion = away_stats.get("shot_conversion_rate", 0.1)
        
        base_home_xg = 1.35 + (home_conversion * 3.0)
        base_away_xg = 1.10 + (away_conversion * 2.5)
        
        # Defense weakness factor: opponent's defensive quality affects xG
        # Higher shots on target against = weaker defense
        away_def_weakness = away_stats.get("shot_accuracy", 0.35)  # opponent's shot accuracy as proxy
        home_def_weakness = home_stats.get("shot_accuracy", 0.35)
        
        # Adjust xG: stronger opponent defense → lower xG
        home_xg = base_home_xg * (1 + form_diff * 0.15) * (0.8 + away_def_weakness * 0.6)
        away_xg = base_away_xg * (1 - form_diff * 0.15) * (0.8 + home_def_weakness * 0.6)
        
        # Apply xG Underperformance Penalty directly to calculated xG
        # If a team chronically underperforms its xG, we subtract that historical difference here
        if hasattr(home_mom_data, 'xg_underperformance') and home_mom_data.xg_underperformance > 0.2:
            home_xg -= min(0.5, home_mom_data.xg_underperformance * 0.5)
            
        if hasattr(away_mom_data, 'xg_underperformance') and away_mom_data.xg_underperformance > 0.2:
            away_xg -= min(0.5, away_mom_data.xg_underperformance * 0.5)
        
        # H2H adjustment (more conservative)
        h2h_avg_goals = h2h_features.get("h2h_avg_goals", 2.5)
        if h2h_avg_goals > 3.0:
            home_xg *= 1.05
            away_xg *= 1.05
        elif h2h_avg_goals < 2.0:
            home_xg *= 0.95
            away_xg *= 0.95
        
        # Clamp xG to reasonable range
        home_xg = max(0.5, min(3.5, home_xg))
        away_xg = max(0.3, min(3.0, away_xg))
        
        # Calculate confidence
        # Higher when ELO, H2H, and Form all agree
        elo_winner = "H" if elo_home > max(elo_draw, elo_away) else ("A" if elo_away > elo_draw else "D")
        h2h_winner = "H" if h2h_home_rate > h2h_away_rate else "A"
        form_winner = "H" if form_diff > 0.1 else ("A" if form_diff < -0.1 else "D")
        
        agreement = sum([
            elo_winner == h2h_winner,
            elo_winner == form_winner,
            h2h_winner == form_winner
        ])
        
        max_prob = max(final_home, final_draw, final_away)
        confidence = max_prob * 100 * (0.7 + agreement * 0.1)
        
        # Collect Raw Features for XGBoost
        # Note: home_mom_data is an object now
        def get_rate(val): return val if val is not None else 0.5
        
        raw_features = {
            **elo_features,  # 8 features
            
            # Form Features (need key mapping to match extract_training_data.py)
            "home_goals_avg": 1.5 + home_mom_data.goals_trend, # Proxy
            "home_conceded_avg": 1.5 - home_mom_data.conceded_trend, # Proxy
            "away_goals_avg": 1.5 + away_mom_data.goals_trend,
            "away_conceded_avg": 1.5 - away_mom_data.conceded_trend,
            
            "home_clean_sheet_rate": 0.2, # Not in new MomentumData
            "away_clean_sheet_rate": 0.2,
            "home_scoring_rate": 0.8,
            "away_scoring_rate": 0.8,
            
            "home_winning_streak": home_mom_data.winning_streak,
            "away_winning_streak": away_mom_data.winning_streak,
            "home_unbeaten_streak": home_mom_data.unbeaten_streak,
            "away_unbeaten_streak": away_mom_data.unbeaten_streak,
            
            # H2H Features
            **h2h_features,
            
            # Team Stats
            "home_avg_possession": home_stats.get("avg_possession", 0.5),
            "away_avg_possession": away_stats.get("avg_possession", 0.5),
            "home_avg_shots_on_target": home_stats.get("avg_shots_on_target", 3.5),
            "away_avg_shots_on_target": away_stats.get("avg_shots_on_target", 3.5),
            "home_shot_conversion": home_stats.get("shot_conversion_rate", 0.1),
            "away_shot_conversion": away_stats.get("shot_conversion_rate", 0.1),
            "home_avg_corners": home_stats.get("avg_corners", 4.5),
            "away_avg_corners": away_stats.get("avg_corners", 4.5),
            
            # Derived
            "home_xga": 1.5 - home_mom_data.conceded_trend, # reusing as proxy
            "away_xga": 1.5 - away_mom_data.conceded_trend
        }
        
        return TeamPrediction(
            home_win_prob=final_home,
            draw_prob=final_draw,
            away_win_prob=final_away,
            home_xg=home_xg,
            away_xg=away_xg,
            form_advantage=form_diff,
            h2h_advantage=h2h_home_rate - h2h_away_rate,
            elo_diff=elo_features.get("elo_diff", 0),
            confidence=confidence,
            raw_features=raw_features
        )


# Singleton
_engine: Optional[TeamPredictorEngine] = None


def get_team_predictor() -> TeamPredictorEngine:
    global _engine
    if _engine is None:
        _engine = TeamPredictorEngine()
    return _engine


if __name__ == "__main__":
    engine = get_team_predictor()
    
    print("\n🧪 Team Predictor Engine Test")
    print("=" * 50)
    
    # Test with sample IDs
    pred = engine.predict(
        home_team_id="test_home",
        away_team_id="test_away",
        match_date_ms=1707393600000
    )
    
    print(f"\n📊 Prediction:")
    for k, v in pred.to_dict().items():
        print(f"   {k}: {v}")