import uuid
from datetime import datetime, timezone
from typing import Any

from sqlalchemy import JSON, Boolean, DateTime, Float, ForeignKey, Integer, String, Text
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.db.database import Base


def _now() -> datetime:
    return datetime.now(timezone.utc)


def _uuid() -> str:
    return str(uuid.uuid4())


class Design(Base):
    __tablename__ = "designs"

    id: Mapped[str] = mapped_column(String, primary_key=True, default=_uuid)
    name: Mapped[str] = mapped_column(String, nullable=False)
    design_type: Mapped[str] = mapped_column(String, nullable=False, default="network")
    icon: Mapped[str | None] = mapped_column(String, nullable=True, default="dashboard")
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now)
    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now, onupdate=_now)


class Node(Base):
    __tablename__ = "nodes"

    id: Mapped[str] = mapped_column(String, primary_key=True, default=_uuid)
    type: Mapped[str] = mapped_column(String, nullable=False)
    label: Mapped[str] = mapped_column(String, nullable=False)
    design_id: Mapped[str | None] = mapped_column(String, ForeignKey("designs.id", ondelete="SET NULL"), nullable=True)
    hostname: Mapped[str | None] = mapped_column(String)
    ip: Mapped[str | None] = mapped_column(String)
    mac: Mapped[str | None] = mapped_column(String)
    os: Mapped[str | None] = mapped_column(String)
    status: Mapped[str] = mapped_column(String, default="unknown")
    check_method: Mapped[str | None] = mapped_column(String)
    check_target: Mapped[str | None] = mapped_column(String)
    services: Mapped[list[Any]] = mapped_column(JSON, default=list)
    notes: Mapped[str | None] = mapped_column(Text)
    pos_x: Mapped[float] = mapped_column(Float, default=0)
    pos_y: Mapped[float] = mapped_column(Float, default=0)
    parent_id: Mapped[str | None] = mapped_column(String, ForeignKey("nodes.id", ondelete="CASCADE"))
    container_mode: Mapped[bool] = mapped_column(Boolean, default=False)
    custom_colors: Mapped[dict[str, Any] | None] = mapped_column(JSON, nullable=True)
    custom_icon: Mapped[str | None] = mapped_column(String, nullable=True)
    cpu_count: Mapped[int | None] = mapped_column(Integer, nullable=True)
    cpu_model: Mapped[str | None] = mapped_column(String, nullable=True)
    ram_gb: Mapped[float | None] = mapped_column(Float, nullable=True)
    disk_gb: Mapped[float | None] = mapped_column(Float, nullable=True)
    show_hardware: Mapped[bool] = mapped_column(Boolean, default=False)
    show_port_numbers: Mapped[bool] = mapped_column(Boolean, default=False)
    properties: Mapped[list[Any]] = mapped_column(JSON, default=list)
    width: Mapped[float | None] = mapped_column(Float, nullable=True)
    height: Mapped[float | None] = mapped_column(Float, nullable=True)
    bottom_handles: Mapped[int] = mapped_column(Integer, default=1)
    top_handles: Mapped[int] = mapped_column(Integer, default=1)
    left_handles: Mapped[int] = mapped_column(Integer, default=0)
    right_handles: Mapped[int] = mapped_column(Integer, default=0)
    ieee_address: Mapped[str | None] = mapped_column(String, index=True, nullable=True)
    last_seen: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))
    last_scan: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))
    response_time_ms: Mapped[int | None] = mapped_column(Integer)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now)
    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now, onupdate=_now)
    children: Mapped[list["Node"]] = relationship("Node", back_populates="parent")
    parent: Mapped["Node | None"] = relationship("Node", back_populates="children", remote_side=[id])


class Edge(Base):
    __tablename__ = "edges"

    id: Mapped[str] = mapped_column(String, primary_key=True, default=_uuid)
    source: Mapped[str] = mapped_column(String, ForeignKey("nodes.id", ondelete="CASCADE"))
    target: Mapped[str] = mapped_column(String, ForeignKey("nodes.id", ondelete="CASCADE"))
    design_id: Mapped[str | None] = mapped_column(String, ForeignKey("designs.id", ondelete="SET NULL"), nullable=True)
    type: Mapped[str] = mapped_column(String, default="ethernet")
    label: Mapped[str | None] = mapped_column(String)
    vlan_id: Mapped[int | None] = mapped_column(Integer)
    speed: Mapped[str | None] = mapped_column(String)
    custom_color: Mapped[str | None] = mapped_column(String)
    path_style: Mapped[str | None] = mapped_column(String)
    line_style: Mapped[str | None] = mapped_column(String)
    width_mult: Mapped[float | None] = mapped_column(Float)
    animated: Mapped[str] = mapped_column(String, nullable=False, default='none')
    marker_start: Mapped[str] = mapped_column(String, nullable=False, default='none')
    marker_end: Mapped[str] = mapped_column(String, nullable=False, default='none')
    source_handle: Mapped[str | None] = mapped_column(String)
    target_handle: Mapped[str | None] = mapped_column(String)
    waypoints: Mapped[list[dict[str, float]] | None] = mapped_column(JSON, nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now)


class CanvasState(Base):
    __tablename__ = "canvas_state"

    design_id: Mapped[str] = mapped_column(String, ForeignKey("designs.id", ondelete="CASCADE"), primary_key=True)
    viewport: Mapped[dict[str, Any]] = mapped_column(JSON, default=dict)
    custom_style: Mapped[dict[str, Any] | None] = mapped_column(JSON, nullable=True)
    saved_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now)


class PendingDevice(Base):
    __tablename__ = "pending_devices"
    # Permit the plain (non-Mapped[]) annotations on the transient request-only
    # attributes below; without this SQLAlchemy 2.0 tries to map them as columns.
    __allow_unmapped__ = True

    id: Mapped[str] = mapped_column(String, primary_key=True, default=_uuid)
    ip: Mapped[str | None] = mapped_column(String, nullable=True)
    mac: Mapped[str | None] = mapped_column(String)
    hostname: Mapped[str | None] = mapped_column(String)
    os: Mapped[str | None] = mapped_column(String)
    services: Mapped[list[Any]] = mapped_column(JSON, default=list)
    suggested_type: Mapped[str | None] = mapped_column(String)
    status: Mapped[str] = mapped_column(String, default="pending")
    discovery_source: Mapped[str | None] = mapped_column(String)
    ieee_address: Mapped[str | None] = mapped_column(String, index=True, nullable=True, unique=True)
    friendly_name: Mapped[str | None] = mapped_column(String, nullable=True)
    device_subtype: Mapped[str | None] = mapped_column(String, nullable=True)
    model: Mapped[str | None] = mapped_column(String, nullable=True)
    vendor: Mapped[str | None] = mapped_column(String, nullable=True)
    lqi: Mapped[int | None] = mapped_column(Integer, nullable=True)
    # Display properties carried from discovery (e.g. Proxmox specs: CPU/RAM/Disk,
    # VMID). Generic NodeProperty shape {key,value,icon,visible}; merged into the
    # Node's properties on approve. Empty for scan/mesh sources that don't set it.
    properties: Mapped[list[Any]] = mapped_column(JSON, default=list)
    discovered_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now)

    # Transient (not persisted): populated per-request by the scan routes to report
    # how many canvases this device already appears on. Not a mapped column.
    canvas_count: int = 0
    # Transient (not persisted): timestamps from the linked canvas node(s),
    # correlated by ip / ieee_address. None when the device is not on any canvas.
    node_created_at: datetime | None = None
    node_last_scan: datetime | None = None
    node_last_modified: datetime | None = None
    node_last_seen: datetime | None = None


class PendingDeviceLink(Base):
    """Link between two Zigbee endpoints discovered during import.

    Endpoints are addressed by IEEE (stable across re-imports). Either side may
    already exist as a canvas Node (resolved via Node.ieee_address) or still be
    a PendingDevice. On approval, the matching Edge is auto-created when both
    endpoints exist as canvas Nodes.
    """

    __tablename__ = "pending_device_links"

    id: Mapped[str] = mapped_column(String, primary_key=True, default=_uuid)
    source_ieee: Mapped[str] = mapped_column(String, nullable=False, index=True)
    target_ieee: Mapped[str] = mapped_column(String, nullable=False, index=True)
    lqi: Mapped[int | None] = mapped_column(Integer, nullable=True)
    discovery_source: Mapped[str] = mapped_column(String, nullable=False, default="zigbee")
    discovered_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now)


class ScanRun(Base):
    __tablename__ = "scan_runs"

    id: Mapped[str] = mapped_column(String, primary_key=True, default=_uuid)
    status: Mapped[str] = mapped_column(String, default="running")
    kind: Mapped[str] = mapped_column(String, default="ip", server_default="ip")
    ranges: Mapped[list[str]] = mapped_column(JSON, default=list)
    devices_found: Mapped[int] = mapped_column(Integer, default=0)
    started_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=_now)
    finished_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))
    error: Mapped[str | None] = mapped_column(Text)