"""Validation report generator for scraped data."""

from dataclasses import dataclass, field
from datetime import datetime
from pathlib import Path
from typing import Optional

from ..config import EXPECTED_GAME_COUNTS, OUTPUT_DIR
from ..models.game import Game
from ..models.team import Team
from ..models.stadium import Stadium
from ..models.aliases import ManualReviewItem, ReviewReason


@dataclass
class ValidationSummary:
    """Summary statistics for validation report.

    Attributes:
        total_games: Total number of games scraped
        valid_games: Number of games with all data resolved
        review_count: Number of items needing manual review
        unresolved_teams: Count of unresolved team names
        unresolved_stadiums: Count of unresolved stadium names
        duplicate_games: Count of potential duplicate games
        missing_data: Count of games with missing required data
        expected_games: Expected number of games for this sport
    """

    total_games: int = 0
    valid_games: int = 0
    review_count: int = 0
    unresolved_teams: int = 0
    unresolved_stadiums: int = 0
    duplicate_games: int = 0
    missing_data: int = 0
    expected_games: int = 0

    @property
    def game_coverage(self) -> float:
        """Percentage of expected games scraped."""
        if self.expected_games == 0:
            return 100.0
        return (self.total_games / self.expected_games) * 100

    @property
    def validity_rate(self) -> float:
        """Percentage of games that are valid."""
        if self.total_games == 0:
            return 100.0
        return (self.valid_games / self.total_games) * 100

    @property
    def needs_review(self) -> bool:
        """Check if report requires manual review."""
        return self.review_count > 0

    @property
    def status_emoji(self) -> str:
        """Get status emoji for report header."""
        if self.review_count == 0 and self.game_coverage >= 95:
            return "✅"
        elif self.review_count <= 10 and self.game_coverage >= 80:
            return "⚠️"
        else:
            return "❌"


@dataclass
class ValidationReport:
    """Complete validation report for a sport/season.

    Attributes:
        sport: Sport code
        season: Season start year
        source: Name of the data source used
        summary: Summary statistics
        review_items: Items requiring manual review
        games: All scraped games
        teams: All teams
        stadiums: All stadiums
        generated_at: Timestamp of report generation
    """

    sport: str
    season: int
    source: str
    summary: ValidationSummary
    review_items: list[ManualReviewItem] = field(default_factory=list)
    games: list[Game] = field(default_factory=list)
    teams: list[Team] = field(default_factory=list)
    stadiums: list[Stadium] = field(default_factory=list)
    generated_at: datetime = field(default_factory=datetime.now)

    def to_markdown(self) -> str:
        """Generate markdown report.

        Returns:
            Complete markdown report as string
        """
        lines = []

        # Header
        season_str = f"{self.season}-{str(self.season + 1)[-2:]}"
        lines.append(f"# Validation Report: {self.sport.upper()} {season_str}")
        lines.append("")
        lines.append(f"**Generated**: {self.generated_at.strftime('%Y-%m-%d %H:%M:%S')} UTC")
        lines.append(f"**Source**: {self.source}")
        lines.append(f"**Status**: {self.summary.status_emoji} {'Needs Review' if self.summary.needs_review else 'Ready'}")
        lines.append("")

        # Summary table
        lines.append("## Summary")
        lines.append("")
        lines.append("| Metric | Count |")
        lines.append("|--------|-------|")
        lines.append(f"| Total Games | {self.summary.total_games:,} |")
        lines.append(f"| Valid Games | {self.summary.valid_games:,} |")
        lines.append(f"| Expected Games | {self.summary.expected_games:,} |")
        lines.append(f"| Coverage | {self.summary.game_coverage:.1f}% |")
        lines.append(f"| Manual Review | {self.summary.review_count} |")
        lines.append(f"| Unresolved Teams | {self.summary.unresolved_teams} |")
        lines.append(f"| Unresolved Stadiums | {self.summary.unresolved_stadiums} |")
        lines.append(f"| Duplicate Games | {self.summary.duplicate_games} |")
        lines.append(f"| Missing Data | {self.summary.missing_data} |")
        lines.append("")

        # Manual review section
        if self.review_items:
            lines.append("## Manual Review Required")
            lines.append("")

            # Group by reason
            by_reason: dict[ReviewReason, list[ManualReviewItem]] = {}
            for item in self.review_items:
                if item.reason not in by_reason:
                    by_reason[item.reason] = []
                by_reason[item.reason].append(item)

            for reason, items in sorted(by_reason.items(), key=lambda x: x[0].value):
                reason_title = reason.value.replace("_", " ").title()
                lines.append(f"### {reason_title} ({len(items)})")
                lines.append("")

                for item in items[:10]:  # Limit to first 10 per category
                    lines.append(item.to_markdown())

                if len(items) > 10:
                    lines.append(f"*... and {len(items) - 10} more items*")
                    lines.append("")

        # Teams section
        lines.append("## Teams")
        lines.append("")
        lines.append(f"Total teams: {len(self.teams)}")
        lines.append("")

        if self.teams:
            lines.append("| ID | Full Name | City | Conference | Division |")
            lines.append("|-----|-----------|------|------------|----------|")
            for team in sorted(self.teams, key=lambda t: t.full_name)[:20]:
                lines.append(
                    f"| `{team.id}` | {team.full_name} | {team.city} | "
                    f"{team.conference or '-'} | {team.division or '-'} |"
                )
            if len(self.teams) > 20:
                lines.append(f"*... and {len(self.teams) - 20} more teams*")
            lines.append("")

        # Stadiums section
        lines.append("## Stadiums")
        lines.append("")
        lines.append(f"Total stadiums: {len(self.stadiums)}")
        lines.append("")

        if self.stadiums:
            lines.append("| ID | Name | City | State |")
            lines.append("|-----|------|------|-------|")
            for stadium in sorted(self.stadiums, key=lambda s: s.name)[:20]:
                lines.append(
                    f"| `{stadium.id}` | {stadium.name} | "
                    f"{stadium.city} | {stadium.state} |"
                )
            if len(self.stadiums) > 20:
                lines.append(f"*... and {len(self.stadiums) - 20} more stadiums*")
            lines.append("")

        # Game samples section
        lines.append("## Game Samples")
        lines.append("")

        if self.games:
            # Show first 10 games
            lines.append("### First 10 Games")
            lines.append("")
            lines.append("| ID | Date | Away | Home | Status |")
            lines.append("|----|------|------|------|--------|")
            for game in self.games[:10]:
                date_str = game.game_date.strftime("%Y-%m-%d")
                lines.append(
                    f"| `{game.id}` | {date_str} | {game.away_team_id} | "
                    f"{game.home_team_id} | {game.status} |"
                )
            lines.append("")

            # Show games with issues
            problem_games = [g for g in self.games if not g.stadium_id]
            if problem_games:
                lines.append("### Games Missing Stadium")
                lines.append("")
                lines.append("| ID | Date | Away | Home | Raw Stadium |")
                lines.append("|----|------|------|------|-------------|")
                for game in problem_games[:10]:
                    date_str = game.game_date.strftime("%Y-%m-%d")
                    lines.append(
                        f"| `{game.id}` | {date_str} | {game.away_team_id} | "
                        f"{game.home_team_id} | {game.raw_stadium or '-'} |"
                    )
                if len(problem_games) > 10:
                    lines.append(f"*... and {len(problem_games) - 10} more*")
                lines.append("")

        lines.append("---")
        lines.append("")
        lines.append("*Generated by sportstime-parser*")

        return "\n".join(lines)

    def save(self, output_dir: Optional[Path] = None) -> Path:
        """Save report to markdown file.

        Args:
            output_dir: Directory to save to (default: OUTPUT_DIR)

        Returns:
            Path to saved file
        """
        if output_dir is None:
            output_dir = OUTPUT_DIR

        output_dir.mkdir(parents=True, exist_ok=True)

        filename = f"validation_{self.sport}_{self.season}.md"
        filepath = output_dir / filename

        with open(filepath, "w", encoding="utf-8") as f:
            f.write(self.to_markdown())

        return filepath


def generate_report(
    sport: str,
    season: int,
    source: str,
    games: list[Game],
    teams: list[Team],
    stadiums: list[Stadium],
    review_items: list[ManualReviewItem],
) -> ValidationReport:
    """Generate a validation report from scraped data.

    Args:
        sport: Sport code
        season: Season start year
        source: Data source name
        games: List of scraped games
        teams: List of teams
        stadiums: List of stadiums
        review_items: Items requiring review

    Returns:
        Complete ValidationReport
    """
    # Calculate summary
    summary = ValidationSummary(
        total_games=len(games),
        expected_games=EXPECTED_GAME_COUNTS.get(sport, 0),
        review_count=len(review_items),
    )

    # Count review item types
    for item in review_items:
        if item.reason == ReviewReason.UNRESOLVED_TEAM:
            summary.unresolved_teams += 1
        elif item.reason == ReviewReason.UNRESOLVED_STADIUM:
            summary.unresolved_stadiums += 1
        elif item.reason == ReviewReason.DUPLICATE_GAME:
            summary.duplicate_games += 1
        elif item.reason == ReviewReason.MISSING_DATA:
            summary.missing_data += 1

    # Count valid games (games with all required data)
    valid_count = 0
    for game in games:
        if game.home_team_id and game.away_team_id:
            valid_count += 1

    summary.valid_games = valid_count

    return ValidationReport(
        sport=sport,
        season=season,
        source=source,
        summary=summary,
        review_items=review_items,
        games=games,
        teams=teams,
        stadiums=stadiums,
    )


def detect_duplicate_games(games: list[Game]) -> list[ManualReviewItem]:
    """Detect potential duplicate games.

    Duplicates are identified by having the same:
    - Home team
    - Away team
    - Date (ignoring time)

    Args:
        games: List of games to check

    Returns:
        List of ManualReviewItems for duplicates
    """
    from uuid import uuid4

    seen: dict[str, Game] = {}
    duplicates: list[ManualReviewItem] = []

    for game in games:
        # Create a key for the game
        key = (
            f"{game.home_team_id}_{game.away_team_id}_"
            f"{game.game_date.strftime('%Y%m%d')}"
        )

        if key in seen:
            # Skip if it's a doubleheader (has game_number)
            if game.game_number:
                continue

            existing = seen[key]
            duplicates.append(
                ManualReviewItem(
                    id=f"dup_{uuid4().hex[:8]}",
                    reason=ReviewReason.DUPLICATE_GAME,
                    sport=game.sport,
                    raw_value=f"{game.id} vs {existing.id}",
                    context={
                        "game1_id": existing.id,
                        "game2_id": game.id,
                        "date": game.game_date.strftime("%Y-%m-%d"),
                        "home": game.home_team_id,
                        "away": game.away_team_id,
                    },
                    game_date=game.game_date.date(),
                )
            )
        else:
            seen[key] = game

    return duplicates


def validate_games(games: list[Game]) -> list[ManualReviewItem]:
    """Validate games and return issues found.

    Checks:
    - Missing stadium IDs
    - Missing team IDs
    - Invalid dates
    - Duplicate games

    Args:
        games: List of games to validate

    Returns:
        List of ManualReviewItems for issues
    """
    from uuid import uuid4

    issues: list[ManualReviewItem] = []

    for game in games:
        # Check for missing stadium
        if not game.stadium_id:
            issues.append(
                ManualReviewItem(
                    id=f"missing_{uuid4().hex[:8]}",
                    reason=ReviewReason.MISSING_DATA,
                    sport=game.sport,
                    raw_value=f"Game {game.id} missing stadium",
                    context={
                        "game_id": game.id,
                        "field": "stadium_id",
                        "raw_stadium": game.raw_stadium,
                    },
                    source_url=game.source_url,
                    game_date=game.game_date.date(),
                )
            )

    # Check for duplicates
    dup_issues = detect_duplicate_games(games)
    issues.extend(dup_issues)

    return issues