import random
import uuid

from datetime import timedelta
from django.db import models
from django.db.models import UniqueConstraint
from django.db.models.signals import post_save
from django.dispatch import receiver
from django.conf import settings
from django.utils import timezone

from apps.lyric.models import Token


class Room(models.Model):
    GATHERING = "GATHERING"
    OPEN = "OPEN"
    RENEWAL_DUE = "RENEWAL_DUE"
    GATE_STATUS_CHOICES = [
        (GATHERING, "GATHERING GAMERS"),
        (OPEN, "Open"),
        (RENEWAL_DUE, "Renewal Due"),
    ]

    PRIVATE = "PRIVATE"
    PUBLIC = "PUBLIC"
    INVITE_ONLY = "INVITE ONLY"
    VISIBILITY_CHOICES = [
        (PRIVATE, "Private"),
        (PUBLIC, "Public"),
        (INVITE_ONLY, "Invite Only"),
    ]

    ROLE_SELECT = "ROLE_SELECT"
    SIG_SELECT = "SIG_SELECT"
    SKY_SELECT = "SKY_SELECT"
    IN_GAME = "IN_GAME"
    TABLE_STATUS_CHOICES = [
        (ROLE_SELECT, "Role Select"),
        (SIG_SELECT, "Significator Select"),
        (SKY_SELECT, "Sky Select"),
        (IN_GAME, "In Game"),
    ]

    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    name = models.CharField(max_length=200)
    owner = models.ForeignKey(
        settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="owned_rooms"
    )
    visibility = models.CharField(max_length=20, choices=VISIBILITY_CHOICES, default=PRIVATE)
    gate_status = models.CharField(max_length=20, choices=GATE_STATUS_CHOICES, default=GATHERING)
    table_status = models.CharField(
        max_length=20, choices=TABLE_STATUS_CHOICES, null=True, blank=True
    )
    sig_select_started_at = models.DateTimeField(null=True, blank=True)
    renewal_period = models.DurationField(null=True, blank=True, default=timedelta(days=7))
    created_at = models.DateTimeField(auto_now_add=True)
    board_state = models.JSONField(default=dict)
    seed_count = models.IntegerField(default=12)


class GateSlot(models.Model):
    EMPTY = "EMPTY"
    RESERVED = "RESERVED"
    FILLED = "FILLED"
    STATUS_CHOICES = [
        (EMPTY, "Empty"),
        (RESERVED, "Reserved"),
        (FILLED, "Filled"),
    ]

    room = models.ForeignKey(Room, on_delete=models.CASCADE, related_name="gate_slots")
    slot_number = models.IntegerField()
    gamer = models.ForeignKey(
        settings.AUTH_USER_MODEL, null=True, blank=True,
        on_delete=models.SET_NULL, related_name="gate_slots"
    )
    funded_by = models.ForeignKey(
        settings.AUTH_USER_MODEL, null=True, blank=True,
        on_delete=models.SET_NULL, related_name="funded_slots"
    )
    status = models.CharField(max_length=10, choices=STATUS_CHOICES, default=EMPTY)
    reserved_at = models.DateTimeField(null=True, blank=True)
    filled_at = models.DateTimeField(null=True, blank=True)
    debited_token_type = models.CharField(max_length=8, null=True, blank=True)
    debited_token_expires_at = models.DateTimeField(null=True, blank=True)


class RoomInvite(models.Model):
    PENDING = "PENDING"
    ACCEPTED = "ACCEPTED"
    DECLINED = "DECLINED"
    STATUS_CHOICES = [
        (PENDING, "Pending"),
        (ACCEPTED, "Accepted"),
        (DECLINED, "Declined"),
    ]

    room = models.ForeignKey(Room, on_delete=models.CASCADE, related_name="invites")
    inviter = models.ForeignKey(
        settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="sent_invites"
    )
    invitee_email = models.EmailField()
    status = models.CharField(max_length=10, choices=STATUS_CHOICES, default=PENDING)
    created_at = models.DateTimeField(auto_now_add=True)


@receiver(post_save, sender=Room)
def create_gate_slots(sender, instance, created, **kwargs):
    if created:
        for i in range(1, 7):
            GateSlot.objects.create(room=instance, slot_number=i)


def select_token(user):
    if user.is_staff:
        pass_token = user.tokens.filter(token_type=Token.PASS).first()
        if pass_token:
            return pass_token
    coin = user.tokens.filter(token_type=Token.COIN, current_room__isnull=True).first()
    if coin:
        return coin
    free = user.tokens.filter(
        token_type=Token.FREE,
        expires_at__gt=timezone.now(),
    ).order_by("expires_at").first()
    if free:
        return free
    return user.tokens.filter(token_type=Token.TITHE).first()


def debit_token(user, slot, token):
    slot.debited_token_type = token.token_type
    if token.token_type == Token.COIN:
        token.current_room = slot.room
        period = slot.room.renewal_period or timedelta(days=7)
        token.next_ready_at = timezone.now() + period
        token.save()
    elif token.token_type == Token.CARTE:
        pass  # current_room already set in drop_token; token not consumed
    elif token.token_type != Token.PASS:
        slot.debited_token_expires_at = token.expires_at
        token.delete()
    slot.gamer = user
    slot.status = GateSlot.FILLED
    slot.filled_at = timezone.now()
    slot.save()

    room = slot.room
    if not room.gate_slots.filter(status=GateSlot.EMPTY).exists():
        room.gate_status = Room.OPEN
        room.save()


SIG_SEAT_ORDER = ["PC", "NC", "EC", "SC", "AC", "BC"]


class TableSeat(models.Model):
    PC = "PC"
    BC = "BC"
    SC = "SC"
    AC = "AC"
    NC = "NC"
    EC = "EC"
    ROLE_CHOICES = [
        (PC, "Player"),
        (BC, "Builder"),
        (SC, "Shepherd"),
        (AC, "Alchemist"),
        (NC, "Narrator"),
        (EC, "Economist"),
    ]
    PARTNER_MAP = {PC: BC, BC: PC, SC: AC, AC: SC, NC: EC, EC: NC}

    room = models.ForeignKey(Room, on_delete=models.CASCADE, related_name="table_seats")
    gamer = models.ForeignKey(
        settings.AUTH_USER_MODEL, null=True, blank=True,
        on_delete=models.SET_NULL, related_name="table_seats"
    )
    slot_number = models.IntegerField()
    role = models.CharField(max_length=2, choices=ROLE_CHOICES, null=True, blank=True)
    role_revealed = models.BooleanField(default=False)
    seat_position = models.IntegerField(null=True, blank=True)
    significator = models.ForeignKey(
        "TarotCard", null=True, blank=True,
        on_delete=models.SET_NULL, related_name="significator_seats",
    )
    deck_variant = models.ForeignKey(
        "DeckVariant", null=True, blank=True,
        on_delete=models.SET_NULL, related_name="active_seats",
    )


class DeckVariant(models.Model):
    """A named deck variant, e.g. Earthman (108 cards) or Fiorentine Minchiate (78 cards)."""

    name = models.CharField(max_length=100, unique=True)
    slug = models.SlugField(unique=True)
    card_count = models.IntegerField()
    description = models.TextField(blank=True)
    is_default = models.BooleanField(default=False)

    @property
    def short_key(self):
        """First dash-separated word of slug — used as an HTML id component."""
        return self.slug.split('-')[0]

    def __str__(self):
        return f"{self.name} ({self.card_count} cards)"


class TarotCard(models.Model):
    MAJOR = "MAJOR"
    MINOR = "MINOR"
    MIDDLE = "MIDDLE"          # Earthman court cards (M/J/Q/K)
    ARCANA_CHOICES = [
        (MAJOR,  "Major Arcana"),
        (MINOR,  "Minor Arcana"),
        (MIDDLE, "Middle Arcana"),
    ]

    WANDS = "WANDS"
    CUPS = "CUPS"
    SWORDS = "SWORDS"
    PENTACLES = "PENTACLES"   # Fiorentine 4th suit
    CROWNS = "CROWNS"         # Earthman 4th suit
    BRANDS = "BRANDS"         # Earthman Wands
    GRAILS = "GRAILS"         # Earthman Cups
    BLADES = "BLADES"         # Earthman Swords
    SUIT_CHOICES = [
        (WANDS,     "Wands"),
        (CUPS,      "Cups"),
        (SWORDS,    "Swords"),
        (PENTACLES, "Pentacles"),
        (CROWNS,    "Crowns"),
        (BRANDS,    "Brands"),
        (GRAILS,    "Grails"),
        (BLADES,    "Blades"),
    ]

    deck_variant = models.ForeignKey(
        DeckVariant, null=True, blank=True,
        on_delete=models.CASCADE, related_name="cards",
    )
    name = models.CharField(max_length=200)
    arcana = models.CharField(max_length=6, choices=ARCANA_CHOICES)
    suit = models.CharField(max_length=10, choices=SUIT_CHOICES, null=True, blank=True)
    icon = models.CharField(max_length=50, blank=True, default='')  # FA icon override (e.g. major arcana)
    number = models.IntegerField()  # 0–21 major (Fiorentine); 0–49 major (Earthman); 1–14 minor
    slug = models.SlugField(max_length=120)
    correspondence = models.CharField(max_length=200, blank=True)  # Tarot / Minchiate equivalent
    group = models.CharField(max_length=100, blank=True)           # Earthman major grouping
    reversal = models.CharField(max_length=200, blank=True, default='')           # reversed-state title; blank = same as name
    levity_qualifier = models.CharField(max_length=100, blank=True, default='')
    gravity_qualifier = models.CharField(max_length=100, blank=True, default='')
    levity_emanation = models.CharField(max_length=200, blank=True, default='')   # polarity-split upright (cards 48-49)
    gravity_emanation = models.CharField(max_length=200, blank=True, default='')
    levity_reversal = models.CharField(max_length=200, blank=True, default='')    # polarity-split reversal (card 48)
    gravity_reversal = models.CharField(max_length=200, blank=True, default='')
    mechanisms = models.JSONField(default=list)    # list of dicts; in-game effects
    articulations = models.JSONField(default=list) # list of dicts; combinatory effects
    keywords_upright = models.JSONField(default=list)
    keywords_reversed = models.JSONField(default=list)
    cautions = models.JSONField(default=list)

    class Meta:
        ordering = ["deck_variant", "arcana", "suit", "number"]
        unique_together = [("deck_variant", "slug")]

    @staticmethod
    def _to_roman(n):
        if n == 0:
            return '0'
        val  = [50, 40, 10,  9,  5,  4,  1]
        syms = ['L','XL','X','IX','V','IV','I']
        result = ''
        for v, s in zip(val, syms):
            while n >= v:
                result += s
                n -= v
        return result

    @property
    def corner_rank(self):
        if self.arcana == self.MAJOR:
            return self._to_roman(self.number)
        court = {11: 'M', 12: 'J', 13: 'Q', 14: 'K'}
        return court.get(self.number, str(self.number))

    def emanation_for(self, polarity):
        """Return the upright title for a given polarity ('levity' or 'gravity').
        Falls back to name for cards without a polarity split."""
        if polarity == 'levity' and self.levity_emanation:
            return self.levity_emanation
        if polarity == 'gravity' and self.gravity_emanation:
            return self.gravity_emanation
        return self.name

    def reversal_for(self, polarity):
        """Return the reversed title for a given polarity.
        Falls back to reversal (blank = same as emanation_for)."""
        if polarity == 'levity' and self.levity_reversal:
            return self.levity_reversal
        if polarity == 'gravity' and self.gravity_reversal:
            return self.gravity_reversal
        return self.reversal or self.emanation_for(polarity)

    @property
    def name_group(self):
        """Returns 'Group N:' prefix if the name contains ': ', else ''."""
        if ': ' in self.name:
            return self.name.split(': ', 1)[0] + ':'
        return ''

    @property
    def name_title(self):
        """Returns the title after 'Group N: ', or the full name if no colon."""
        if ': ' in self.name:
            return self.name.split(': ', 1)[1]
        return self.name

    @property
    def suit_icon(self):
        if self.icon:
            return self.icon
        if self.arcana == self.MAJOR:
            return ''
        return {
            self.WANDS:     'fa-wand-sparkles',
            self.CUPS:      'fa-trophy',
            self.SWORDS:    'fa-gun',
            self.PENTACLES: 'fa-star',
            self.CROWNS:    'fa-crown',
            self.BRANDS:    'fa-wand-sparkles',
            self.GRAILS:    'fa-trophy',
            self.BLADES:    'fa-gun',
        }.get(self.suit, '')

    @property
    def cautions_json(self):
        import json
        return json.dumps(self.cautions)

    def __str__(self):
        return self.name


class TarotDeck(models.Model):
    """One shuffled deck per room, scoped to the founder's chosen DeckVariant."""

    room = models.OneToOneField(Room, on_delete=models.CASCADE, related_name="tarot_deck")
    deck_variant = models.ForeignKey(
        DeckVariant, null=True, blank=True,
        on_delete=models.SET_NULL, related_name="active_decks",
    )
    drawn_card_ids = models.JSONField(default=list)
    created_at = models.DateTimeField(auto_now_add=True)

    @property
    def remaining_count(self):
        total = self.deck_variant.card_count if self.deck_variant else 0
        return total - len(self.drawn_card_ids)

    def draw(self, n=1):
        """Draw n cards at random. Returns list of (TarotCard, reversed: bool) tuples."""
        available = list(
            TarotCard.objects.filter(deck_variant=self.deck_variant)
            .exclude(id__in=self.drawn_card_ids)
        )
        if len(available) < n:
            raise ValueError(
                f"Not enough cards remaining: {len(available)} available, {n} requested"
            )
        drawn = random.sample(available, n)
        self.drawn_card_ids = self.drawn_card_ids + [card.id for card in drawn]
        self.save(update_fields=["drawn_card_ids"])
        return [(card, random.choice([True, False])) for card in drawn]

    def shuffle(self):
        """Reset the deck so all variant cards are available again."""
        self.drawn_card_ids = []
        self.save(update_fields=["drawn_card_ids"])


# ── SigReservation — provisional card hold during SIG_SELECT ──────────────────

class SigReservation(models.Model):
    LEVITY = 'levity'
    GRAVITY = 'gravity'
    POLARITY_CHOICES = [(LEVITY, 'Levity'), (GRAVITY, 'Gravity')]

    room = models.ForeignKey(Room, on_delete=models.CASCADE, related_name='sig_reservations')
    gamer = models.ForeignKey(
        settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='sig_reservations'
    )
    seat = models.ForeignKey(
        'TableSeat', null=True, blank=True,
        on_delete=models.SET_NULL, related_name='sig_reservation',
    )
    card = models.ForeignKey(
        'TarotCard', on_delete=models.CASCADE, related_name='sig_reservations'
    )
    role = models.CharField(max_length=2)
    polarity = models.CharField(max_length=7, choices=POLARITY_CHOICES)
    reserved_at = models.DateTimeField(auto_now_add=True)
    ready = models.BooleanField(default=False)
    countdown_remaining = models.IntegerField(null=True, blank=True)

    class Meta:
        constraints = [
            UniqueConstraint(
                fields=['room', 'gamer'],
                name='one_sig_reservation_per_gamer_per_room',
            ),
            UniqueConstraint(
                fields=['room', 'card', 'polarity'],
                name='one_reservation_per_card_per_polarity_per_room',
            ),
        ]


# ── Significator deck helpers ─────────────────────────────────────────────────

def _room_deck_variant(room):
    """Return the DeckVariant in use for this room.

    Looks up the deck committed to any TableSeat in the room (all seats share the
    same deck per game).  Falls back to the room owner's equipped_deck for rooms
    created before deck contribution was wired.
    """
    seat = room.table_seats.filter(deck_variant__isnull=False).first()
    if seat:
        return seat.deck_variant
    return room.owner.equipped_deck


def sig_deck_cards(room):
    """Return 36 TarotCard objects forming the Significator deck (18 unique × 2).

    PC/BC pair → BRANDS/WANDS + CROWNS Middle Arcana court cards (11–14): 8 unique
    SC/AC pair → BLADES/SWORDS + GRAILS/CUPS Middle Arcana court cards (11–14): 8 unique
    NC/EC pair → MAJOR arcana numbers 0 and 1:                               2 unique
    Total: 18 unique × 2 (levity + gravity piles) = 36 cards.
    """
    deck_variant = _room_deck_variant(room)
    if deck_variant is None:
        return []
    wands_crowns = list(TarotCard.objects.filter(
        deck_variant=deck_variant,
        arcana=TarotCard.MIDDLE,
        suit__in=[TarotCard.WANDS, TarotCard.BRANDS, TarotCard.CROWNS],
        number__in=[11, 12, 13, 14],
    ))
    swords_cups = list(TarotCard.objects.filter(
        deck_variant=deck_variant,
        arcana=TarotCard.MIDDLE,
        suit__in=[TarotCard.SWORDS, TarotCard.BLADES, TarotCard.CUPS, TarotCard.GRAILS],
        number__in=[11, 12, 13, 14],
    ))
    major = list(TarotCard.objects.filter(
        deck_variant=deck_variant,
        arcana=TarotCard.MAJOR,
        number__in=[0, 1],
    ))
    unique_cards = wands_crowns + swords_cups + major  # 18 unique
    return unique_cards + unique_cards  # × 2 = 36


def _sig_unique_cards(room):
    """Return the 18 unique TarotCard objects that form one sig pile."""
    deck_variant = _room_deck_variant(room)
    if deck_variant is None:
        return []
    wands_crowns = list(TarotCard.objects.filter(
        deck_variant=deck_variant,
        arcana=TarotCard.MIDDLE,
        suit__in=[TarotCard.WANDS, TarotCard.BRANDS, TarotCard.CROWNS],
        number__in=[11, 12, 13, 14],
    ))
    swords_cups = list(TarotCard.objects.filter(
        deck_variant=deck_variant,
        arcana=TarotCard.MIDDLE,
        suit__in=[TarotCard.SWORDS, TarotCard.BLADES, TarotCard.CUPS, TarotCard.GRAILS],
        number__in=[11, 12, 13, 14],
    ))
    major = list(TarotCard.objects.filter(
        deck_variant=deck_variant,
        arcana=TarotCard.MAJOR,
        number__in=[0, 1],
    ))
    return wands_crowns + swords_cups + major


def _filter_major_unlocks(cards, user):
    """Remove Nomad (0) and Schizo (1) unless the user has the matching Note unlock."""
    if user is None or not user.is_authenticated:
        return [c for c in cards if c.arcana != TarotCard.MAJOR]
    earned = set(user.notes.values_list("slug", flat=True))
    return [
        c for c in cards
        if c.arcana != TarotCard.MAJOR
        or (c.number == 0 and "nomad"  in earned)
        or (c.number == 1 and "schizo" in earned)
    ]


def levity_sig_cards(room, user=None):
    """Cards available to the levity group (PC/NC/SC), filtered by user's Note unlocks."""
    return _filter_major_unlocks(_sig_unique_cards(room), user)


def gravity_sig_cards(room, user=None):
    """Cards available to the gravity group (BC/EC/AC), filtered by user's Note unlocks."""
    return _filter_major_unlocks(_sig_unique_cards(room), user)


def sig_seat_order(room):
    """Return TableSeats in canonical PC→NC→EC→SC→AC→BC order."""
    _order = {r: i for i, r in enumerate(SIG_SEAT_ORDER)}
    seats = list(room.table_seats.all())
    return sorted(seats, key=lambda s: _order.get(s.role, 99))


def active_sig_seat(room):
    """Return the first seat without a significator in canonical order, or None."""
    for seat in sig_seat_order(room):
        if seat.significator_id is None:
            return seat
    return None


# ── Astrological reference tables (seeded, never user-edited) ─────────────────

class Sign(models.Model):
    FIRE  = 'Fire'
    EARTH = 'Earth'
    AIR   = 'Air'
    WATER = 'Water'
    ELEMENT_CHOICES = [(e, e) for e in (FIRE, EARTH, AIR, WATER)]

    CARDINAL = 'Cardinal'
    FIXED    = 'Fixed'
    MUTABLE  = 'Mutable'
    MODALITY_CHOICES = [(m, m) for m in (CARDINAL, FIXED, MUTABLE)]

    name         = models.CharField(max_length=20, unique=True)
    symbol       = models.CharField(max_length=5)   # ♈ ♉ … ♓
    element      = models.CharField(max_length=5,  choices=ELEMENT_CHOICES)
    modality     = models.CharField(max_length=8,  choices=MODALITY_CHOICES)
    order        = models.PositiveSmallIntegerField(unique=True)  # 0–11, Aries first
    start_degree = models.FloatField()                            # 0, 30, 60 … 330

    class Meta:
        ordering = ['order']

    def __str__(self):
        return self.name


class Planet(models.Model):
    name   = models.CharField(max_length=20, unique=True)
    symbol = models.CharField(max_length=5)   # ☉ ☽ ☿ ♀ ♂ ♃ ♄ ♅ ♆ ♇
    order  = models.PositiveSmallIntegerField(unique=True)  # 0–9, Sun first

    class Meta:
        ordering = ['order']

    def __str__(self):
        return self.name


class AspectType(models.Model):
    name   = models.CharField(max_length=20, unique=True)
    symbol = models.CharField(max_length=5)   # ☌ ⚹ □ △ ☍
    angle  = models.PositiveSmallIntegerField()  # 0, 60, 90, 120, 180
    orb    = models.FloatField()                 # max allowed orb in degrees

    class Meta:
        ordering = ['angle']

    def __str__(self):
        return self.name


class HouseLabel(models.Model):
    """Life-area label for each of the 12 astrological houses (distinctions)."""

    number   = models.PositiveSmallIntegerField(unique=True)  # 1–12
    name     = models.CharField(max_length=30)
    keywords = models.CharField(max_length=100, blank=True)

    class Meta:
        ordering = ['number']

    def __str__(self):
        return f"{self.number}: {self.name}"


# ── Character ─────────────────────────────────────────────────────────────────

class Character(models.Model):
    """A gamer's player-character for one seat in one game session.

    Lifecycle:
      - Created (draft) when gamer opens PICK SKY overlay.
      - confirmed_at set on confirm → locked.
      - retired_at set on retirement → archived (seat may hold a new Character).

    Active character for a seat: confirmed_at__isnull=False, retired_at__isnull=True.
    """

    PORPHYRY  = 'O'
    PLACIDUS  = 'P'
    KOCH      = 'K'
    WHOLE     = 'W'
    HOUSE_SYSTEM_CHOICES = [
        (PORPHYRY, 'Porphyry'),
        (PLACIDUS, 'Placidus'),
        (KOCH,     'Koch'),
        (WHOLE,    'Whole Sign'),
    ]

    # ── seat relationship ─────────────────────────────────────────────────
    seat = models.ForeignKey(
        TableSeat, on_delete=models.CASCADE, related_name='characters',
    )

    # ── significator (set at PICK SKY) ────────────────────────────────────
    significator = models.ForeignKey(
        TarotCard, null=True, blank=True,
        on_delete=models.SET_NULL, related_name='character_significators',
    )

    # ── natus input (what the gamer entered) ─────────────────────────────
    birth_dt    = models.DateTimeField(null=True, blank=True)   # UTC
    birth_lat   = models.DecimalField(max_digits=9, decimal_places=6, null=True, blank=True)
    birth_lon   = models.DecimalField(max_digits=9, decimal_places=6, null=True, blank=True)
    birth_place = models.CharField(max_length=200, blank=True)  # display string only
    house_system = models.CharField(
        max_length=1, choices=HOUSE_SYSTEM_CHOICES, default=PORPHYRY,
    )

    # ── computed natus snapshot (full PySwiss response) ───────────────────
    chart_data  = models.JSONField(null=True, blank=True)

    # ── celtic cross spread (added at PICK SEA) ───────────────────────────
    celtic_cross = models.JSONField(null=True, blank=True)

    # ── lifecycle ─────────────────────────────────────────────────────────
    created_at   = models.DateTimeField(auto_now_add=True)
    confirmed_at = models.DateTimeField(null=True, blank=True)
    retired_at   = models.DateTimeField(null=True, blank=True)

    class Meta:
        ordering = ['-created_at']

    def __str__(self):
        status = 'confirmed' if self.confirmed_at else 'draft'
        return f"Character(seat={self.seat_id}, {status})"

    @property
    def is_confirmed(self):
        return self.confirmed_at is not None

    @property
    def is_active(self):
        return self.confirmed_at is not None and self.retired_at is None