import uuid

from datetime import timedelta
from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
from django.db import models
from django.db.models.signals import post_save
from django.dispatch import receiver
from django.urls import reverse
from django.utils import timezone


# ── Pronoun preference set ────────────────────────────────────────────────
# Drives provenance prose ("embodies as their Significator …") and any other
# user-facing referent. Default is pluralism (singular they) so a brand-new
# account renders neutrally; bawlmorese (yo/yo/yos) is the original Earthman
# default kept available as a Baltimore-flavoured option.

PRONOUN_CHOICES = [
    ("pluralism",   "they/them/their"),
    ("bawlmorese",  "yo/yo/yos"),
    ("misogyny",    "he/him/his"),
    ("misandry",    "she/her/hers"),
    ("misanthropy", "it/it/its"),
]
PRONOUN_TABLE = {
    "pluralism":   {"subj": "they", "obj": "them", "poss": "their"},
    "bawlmorese":  {"subj": "yo",   "obj": "yo",   "poss": "yos"},
    "misogyny":    {"subj": "he",   "obj": "him",  "poss": "his"},
    "misandry":    {"subj": "she",  "obj": "her",  "poss": "hers"},
    "misanthropy": {"subj": "it",   "obj": "it",   "poss": "its"},
}


def resolve_pronouns(pronouns_key):
    """Return (subj, obj, poss) for a pronouns key, defaulting to pluralism."""
    row = PRONOUN_TABLE.get(pronouns_key) or PRONOUN_TABLE["pluralism"]
    return row["subj"], row["obj"], row["poss"]


# ── Reserved usernames ────────────────────────────────────────────────────
# Sitewide entities that shouldn't be impersonated by new account names.
# Compared lower-case in username assignment paths (set_profile, etc.).
# `adman` is the system author for Note-unlock + share-invite Lines (seeded
# in lyric/0003_seed_adman). The author's handles (disco, discoman,
# hamildong) are NOT in this set yet — discoman is the founder's actual
# username and existing tests assign it; revisit if/when other-entity
# impersonation becomes a concrete concern.

RESERVED_USERNAMES = frozenset({"adman"})


def is_reserved_username(name, current_user=None):
    """True if `name` is reserved AND not already owned by `current_user`."""
    n = (name or "").strip().lower()
    if not n:
        return False
    if current_user is not None and (current_user.username or "").lower() == n:
        return False
    return n in RESERVED_USERNAMES


def get_or_create_adman():
    """Idempotent fetch of the sitewide `adman` User — system-author for
    Note-unlock + share-invite Lines. Production migrations seed it once
    (lyric/0003_seed_adman); TransactionTestCase flushes the row between
    tests, so view code that authors Lines as adman calls this helper."""
    from django.contrib.auth.hashers import make_password
    adman, _ = User.objects.get_or_create(
        username="adman",
        defaults={
            "email": "adman@earthmanrpg.local",
            "password": make_password(None),
            "is_staff": False,
            "is_superuser": False,
            "searchable": False,
        },
    )
    return adman


class UserManager(BaseUserManager):
    def create_user(self, email):
        user = self.model(email=email)
        user.set_unusable_password()
        user.save(using=self._db)
        return user

    def create_superuser(self, email, password):
        user = self.model(email=email, is_staff=True, is_superuser=True)
        user.set_password(password)
        user.save(using=self._db)
        return user

class LoginToken(models.Model):
    email = models.EmailField()
    uid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)

class User(AbstractBaseUser):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    email = models.EmailField(unique=True)
    username = models.CharField(max_length=35, unique=True, null=True, blank=True)
    searchable = models.BooleanField(default=False)
    palette = models.CharField(max_length=32, default="palette-default")
    stripe_customer_id = models.CharField(max_length=255, null=True, blank=True)
    equipped_trinket = models.ForeignKey(
        "Token", null=True, blank=True,
        on_delete=models.SET_NULL, related_name="+",
    )
    equipped_deck = models.ForeignKey(
        "epic.DeckVariant", null=True, blank=True,
        on_delete=models.SET_NULL, related_name="+",
    )
    unlocked_decks = models.ManyToManyField(
        "epic.DeckVariant", blank=True, related_name="unlocked_by",
    )
    # Asymmetric self M2M — `user.buddies.all()` = people I've explicitly
    # added (or implicitly via post-share / game-invite, which auto-adds
    # the recipient to the inviter's buddies list). `user.added_as_buddy`
    # = the inverse (people who have me in their buddies list); useful
    # for the future "buddy changed username" snapshot-accept flow.
    buddies = models.ManyToManyField(
        "self", symmetrical=False, blank=True, related_name="added_as_buddy",
    )
    active_title = models.ForeignKey(
        "drama.Note", null=True, blank=True,
        on_delete=models.SET_NULL, related_name="+",
    )
    ap_public_key = models.TextField(blank=True, default="")
    ap_private_key = models.TextField(blank=True, default="")

    # Personal natal chart (My Sky) — independent of any game room/character
    sky_birth_dt    = models.DateTimeField(null=True, blank=True)
    sky_birth_lat   = models.DecimalField(max_digits=9, decimal_places=4, null=True, blank=True)
    sky_birth_lon   = models.DecimalField(max_digits=9, decimal_places=4, null=True, blank=True)
    sky_birth_place = models.CharField(max_length=255, blank=True)
    sky_birth_tz    = models.CharField(max_length=64,  blank=True)
    sky_house_system = models.CharField(max_length=1, blank=True, default="O")
    sky_chart_data  = models.JSONField(null=True, blank=True)

    is_staff = models.BooleanField(default=False)
    is_superuser = models.BooleanField(default=False)

    pronouns = models.CharField(
        max_length=16, choices=PRONOUN_CHOICES, default="pluralism",
    )

    objects = UserManager()
    REQUIRED_FIELDS = []
    USERNAME_FIELD = "email"

    @property
    def active_title_display(self):
        """Render-ready string for "{username} the {title}" attributions —
        returns the donned Note's recognition title, or 'Earthman' when no
        Note is donned. The 'Earthman' default mirrors the dashboard greeting
        fallback in dashboard/views.home_page."""
        if self.active_title_id:
            return self.active_title.display_title
        return "Earthman"

    @property
    def pronoun_subj(self):
        return resolve_pronouns(self.pronouns)[0]

    @property
    def pronoun_obj(self):
        return resolve_pronouns(self.pronouns)[1]

    @property
    def pronoun_poss(self):
        return resolve_pronouns(self.pronouns)[2]

    def ensure_keypair(self):
        """Generate and persist an RSA-2048 keypair if not already set."""
        if self.ap_public_key:
            return
        from cryptography.hazmat.primitives.asymmetric import rsa
        from cryptography.hazmat.primitives import serialization
        private_key = rsa.generate_private_key(public_exponent=65537, key_size=2048)
        self.ap_public_key = private_key.public_key().public_bytes(
            serialization.Encoding.PEM,
            serialization.PublicFormat.SubjectPublicKeyInfo,
        ).decode()
        self.ap_private_key = private_key.private_bytes(
            serialization.Encoding.PEM,
            serialization.PrivateFormat.PKCS8,
            serialization.NoEncryption(),
        ).decode()
        self.save(update_fields=["ap_public_key", "ap_private_key"])

    def has_perm(self, perm, obj=None):
        return self.is_superuser
    
    def has_module_perms(self, app_label):
        return self.is_superuser
    
class Wallet(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE, related_name="wallet")
    writs = models.IntegerField(default=0)
    esteem = models.IntegerField(default=0)

    def tooltip_name(self):
        return "Wallet"

    def tooltip_description(self):
        return f"{self.writs} writs · {self.esteem} esteem"

    def tooltip_shoptalk(self):
        return None

    def tooltip_expiry(self):
        return None

    def tooltip_text(self):
        return f"{self.tooltip_name()}: {self.tooltip_description()}"

class Token(models.Model):
    COIN = "coin"
    FREE = "Free"
    TITHE = "tithe"
    PASS = "pass"
    CARTE = "carte"
    TOKEN_TYPE_CHOICES = [
        (COIN, "Coin-on-a-String"),
        (FREE, "Free Token"),
        (TITHE, "Tithe Token"),
        (PASS, "Backstage Pass"),
        (CARTE, "Carte Blanche"),
    ]

    user = models.ForeignKey(User, on_delete=models.CASCADE, related_name="tokens")
    token_type = models.CharField(max_length=8, choices=TOKEN_TYPE_CHOICES)
    expires_at = models.DateTimeField(null=True, blank=True)
    current_room = models.ForeignKey(
        "epic.Room", null=True, blank=True,
        on_delete=models.SET_NULL, related_name="coin_tokens"
    )
    next_ready_at = models.DateTimeField(null=True, blank=True)
    slots_claimed = models.PositiveSmallIntegerField(default=0, blank=True)

    def tooltip_name(self):
        return self.get_token_type_display()
    
    def tooltip_description(self):
        if self.token_type in (self.COIN, self.FREE):
            return "Admit 1 Entry"
        if self.token_type == self.PASS:
            return "Admit All Entry"
        if self.token_type == self.TITHE:
            return "+ Writ bonus"
        if self.token_type == self.CARTE:
            return "Admit up to +6"
        return ""

    def tooltip_expiry(self):
        if self.token_type in (self.COIN, self.PASS, self.CARTE):
            if self.token_type == self.COIN and self.next_ready_at:
                return f"Ready {self.next_ready_at.strftime('%Y-%m-%d')}"
            return "no expiry"
        if self.expires_at:
            return f"Expires {self.expires_at.strftime('%Y-%m-%d')}"
        return ""
    
    def tooltip_room_html(self):
        if not self.current_room_id:
            return ""
        url = reverse("epic:gatekeeper", kwargs={"room_id": self.current_room_id})
        return f'<a href="{url}">{self.current_room.name}</a>'

    def tooltip_shoptalk(self):
        if self.token_type == self.COIN:
            return "\u2026and another after that, and another after that\u2026"
        if self.token_type == self.FREE:
            return "a spot of good fortune"
        if self.token_type == self.PASS:
            return "\u2018Entry fee\u2019? Pal, do you know who you\u2019re talking to?"
        if self.token_type == self.CARTE:
            return "No, I\u2019m afraid we\u2019ll be taking over from here."
        return None

    def tooltip_text(self):
        text = f"{self.tooltip_name()}: {self.tooltip_description()}"
        if self.tooltip_shoptalk():
            text += f" ({self.tooltip_shoptalk()})"
        text += f" \u2014 {self.tooltip_expiry()}"
        return text
    
class PaymentMethod(models.Model):
    user = models.ForeignKey(User, on_delete=models.CASCADE, related_name="payment_methods")
    stripe_pm_id = models.CharField(max_length=255)
    last4 = models.CharField(max_length=4)
    brand = models.CharField(max_length=32)

    def __str__(self):
        return f"{self.brand} ....{self.last4}"
    
@receiver(post_save, sender=User)
def create_wallet_and_tokens(sender, instance, created, **kwargs):
    if not created:
        return
    from apps.epic.models import DeckVariant
    Wallet.objects.create(user=instance, writs=144)
    coin = Token.objects.create(user=instance, token_type=Token.COIN)
    Token.objects.create(
        user=instance,
        token_type=Token.FREE,
        expires_at=timezone.now() + timedelta(days=7),
    )
    if instance.is_staff:
        pass_token = Token.objects.create(user=instance, token_type=Token.PASS)
        instance.equipped_trinket = pass_token
    else:
        instance.equipped_trinket = coin
    earthman = DeckVariant.objects.filter(slug="earthman").first()
    instance.equipped_deck = earthman
    instance.save(update_fields=['equipped_trinket', 'equipped_deck'])
    if earthman:
        instance.unlocked_decks.add(earthman)
    if instance.is_superuser:
        from apps.drama.models import Note
        Note.grant_if_new(instance, "super-schizo")
        Note.grant_if_new(instance, "super-nomad")