from django.db import models
from simple_history.models import HistoricalRecords


class Game(models.Model):
    """
    Game model representing a single game between two teams.
    """
    STATUS_CHOICES = [
        ('scheduled', 'Scheduled'),
        ('in_progress', 'In Progress'),
        ('final', 'Final'),
        ('postponed', 'Postponed'),
        ('cancelled', 'Cancelled'),
        ('suspended', 'Suspended'),
    ]

    id = models.CharField(
        max_length=100,
        primary_key=True,
        help_text='Canonical ID (e.g., game_nba_2025_20251022_bos_lal)'
    )
    sport = models.ForeignKey(
        'core.Sport',
        on_delete=models.CASCADE,
        related_name='games'
    )
    season = models.PositiveSmallIntegerField(
        help_text='Season start year (e.g., 2025 for 2025-26 season)'
    )
    home_team = models.ForeignKey(
        'core.Team',
        on_delete=models.CASCADE,
        related_name='home_games'
    )
    away_team = models.ForeignKey(
        'core.Team',
        on_delete=models.CASCADE,
        related_name='away_games'
    )
    stadium = models.ForeignKey(
        'core.Stadium',
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name='games'
    )
    game_date = models.DateTimeField(
        help_text='Game date and time (UTC)'
    )
    game_number = models.PositiveSmallIntegerField(
        null=True,
        blank=True,
        help_text='Game number for doubleheaders (1 or 2)'
    )
    home_score = models.PositiveSmallIntegerField(
        null=True,
        blank=True
    )
    away_score = models.PositiveSmallIntegerField(
        null=True,
        blank=True
    )
    status = models.CharField(
        max_length=20,
        choices=STATUS_CHOICES,
        default='scheduled'
    )
    is_neutral_site = models.BooleanField(
        default=False,
        help_text='Whether game is at neutral site'
    )
    is_playoff = models.BooleanField(
        default=False,
        help_text='Whether this is a playoff game'
    )
    playoff_round = models.CharField(
        max_length=50,
        blank=True,
        help_text='Playoff round (e.g., Finals, Conference Finals)'
    )

    # Raw scraped values (for debugging/review)
    raw_home_team = models.CharField(
        max_length=200,
        blank=True,
        help_text='Original scraped home team name'
    )
    raw_away_team = models.CharField(
        max_length=200,
        blank=True,
        help_text='Original scraped away team name'
    )
    raw_stadium = models.CharField(
        max_length=200,
        blank=True,
        help_text='Original scraped stadium name'
    )
    source_url = models.URLField(
        blank=True,
        help_text='URL where game was scraped from'
    )

    # Metadata
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    # Audit trail
    history = HistoricalRecords()

    class Meta:
        ordering = ['-game_date', 'sport']
        verbose_name = 'Game'
        verbose_name_plural = 'Games'
        indexes = [
            models.Index(fields=['sport', 'season']),
            models.Index(fields=['sport', 'game_date']),
            models.Index(fields=['home_team', 'season']),
            models.Index(fields=['away_team', 'season']),
            models.Index(fields=['status']),
        ]

    def __str__(self):
        return f"{self.away_team.abbreviation} @ {self.home_team.abbreviation} - {self.game_date.strftime('%Y-%m-%d')}"

    @property
    def is_final(self):
        return self.status == 'final'

    @property
    def winner(self):
        """Return winning team or None if not final."""
        if not self.is_final or self.home_score is None or self.away_score is None:
            return None
        if self.home_score > self.away_score:
            return self.home_team
        elif self.away_score > self.home_score:
            return self.away_team
        return None  # Tie

    @property
    def score_display(self):
        """Return score as 'away_score - home_score' or 'TBD'."""
        if self.home_score is not None and self.away_score is not None:
            return f"{self.away_score} - {self.home_score}"
        return "TBD"