import uuid
from datetime import datetime, timezone
from typing import Optional, TYPE_CHECKING
from sqlalchemy import String, DateTime, ForeignKey, Boolean, Integer, text as sa_text
from sqlalchemy.orm import Mapped, mapped_column, relationship
from sqlalchemy.dialects.postgresql import UUID, JSONB
from app.core.database import Base

if TYPE_CHECKING:
    from app.models.user import User
    from app.models.subscription import Subscription
    from app.models.tree import Tree
    from app.models.category import TreeCategory
    from app.models.tag import TreeTag
    from app.models.step_category import StepCategory
    from app.models.step_library import StepLibrary
    from app.models.account_limit_override import AccountLimitOverride
    from app.models.psa_connection import PsaConnection


class Account(Base):
    __tablename__ = "accounts"

    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    name: Mapped[str] = mapped_column(String(255), nullable=False)
    display_code: Mapped[str] = mapped_column(String(8), unique=True, nullable=False)
    owner_id: Mapped[Optional[uuid.UUID]] = mapped_column(UUID(as_uuid=True), ForeignKey("users.id", ondelete="RESTRICT"), nullable=True)
    stripe_customer_id: Mapped[Optional[str]] = mapped_column(String(255), nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=lambda: datetime.now(timezone.utc))
    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=lambda: datetime.now(timezone.utc), onupdate=lambda: datetime.now(timezone.utc))
    allow_public_shares: Mapped[bool] = mapped_column(
        Boolean,
        nullable=False,
        default=True,
        server_default="true",
        comment="Policy: engineers can create public shares. Only affects NEW shares (grandfathered)."
    )

    # Chat retention settings
    chat_retention_days: Mapped[Optional[int]] = mapped_column(
        Integer, nullable=True, default=90, server_default="90"
    )
    chat_retention_max_count: Mapped[Optional[int]] = mapped_column(
        Integer, nullable=True, default=100, server_default="100"
    )

    # Session policy override (NULL = use Settings.SESSION_*_MINUTES_DEFAULT).
    # Validated at the app layer because the DB cannot see Settings; a DB
    # CHECK constraint covers the both-set case only.
    session_idle_minutes: Mapped[Optional[int]] = mapped_column(Integer, nullable=True)
    session_absolute_minutes: Mapped[Optional[int]] = mapped_column(Integer, nullable=True)

    # Custom branding (Task 9)
    branding_logo_url: Mapped[Optional[str]] = mapped_column(String(500), nullable=True)
    branding_primary_color: Mapped[Optional[str]] = mapped_column(String(7), nullable=True)  # hex like #06b6d4
    branding_company_name: Mapped[Optional[str]] = mapped_column(String(200), nullable=True)
    team_size_bucket: Mapped[Optional[str]] = mapped_column(String(20), nullable=True)
    primary_psa: Mapped[Optional[str]] = mapped_column(String(20), nullable=True)

    # L1 workspace seats
    l1_seats_purchased: Mapped[int] = mapped_column(
        Integer, nullable=False, server_default="0"
    )

    # SSO / SAML groundwork (Task 11)
    sso_enabled: Mapped[bool] = mapped_column(Boolean, default=False, server_default="false")
    sso_provider: Mapped[Optional[str]] = mapped_column(String(20), nullable=True)  # "saml" | "oidc"
    sso_config: Mapped[Optional[dict]] = mapped_column(JSONB, nullable=True)

    # L1 AI tree builder — per-account allowlist of problem categories.
    # Keep this server_default in sync with DEFAULT_L1_CATEGORIES in
    # app/services/l1_category_service.py when adding/removing categories.
    enabled_l1_categories: Mapped[list[str]] = mapped_column(
        JSONB(), nullable=False,
        server_default=sa_text(
            "'[\"password_reset\",\"account_lockout\",\"printer\","
            "\"email_outlook_client\",\"wifi_network_basics\",\"vpn_connect\","
            "\"teams_zoom_av\",\"browser_cache_cookies\",\"peripheral_reconnect\","
            "\"os_restart_update\"]'::jsonb"
        ),
    )

    # Relationships
    owner: Mapped["User"] = relationship("User", foreign_keys=[owner_id], back_populates="owned_account")
    users: Mapped[list["User"]] = relationship("User", foreign_keys="[User.account_id]", back_populates="account")
    subscription: Mapped[Optional["Subscription"]] = relationship("Subscription", back_populates="account", uselist=False)
    trees: Mapped[list["Tree"]] = relationship("Tree", foreign_keys="[Tree.account_id]", back_populates="account")
    categories: Mapped[list["TreeCategory"]] = relationship("TreeCategory", foreign_keys="[TreeCategory.account_id]", back_populates="account")
    tags: Mapped[list["TreeTag"]] = relationship("TreeTag", foreign_keys="[TreeTag.account_id]", back_populates="account")
    step_categories: Mapped[list["StepCategory"]] = relationship("StepCategory", foreign_keys="[StepCategory.account_id]", back_populates="account")
    step_library: Mapped[list["StepLibrary"]] = relationship("StepLibrary", foreign_keys="[StepLibrary.account_id]", back_populates="account")
    limit_override: Mapped[Optional["AccountLimitOverride"]] = relationship("AccountLimitOverride", back_populates="account", uselist=False)
    psa_connection: Mapped[Optional["PsaConnection"]] = relationship("PsaConnection", back_populates="account", uselist=False)