from __future__ import annotations

from typing import Any, Literal

from pydantic import BaseModel

from app.core.process_steps import StepName


StepCategory = Literal["input", "processing", "rendering", "output"]
FieldType = Literal["number", "select", "boolean"]
ExecutionKind = Literal["native", "bridge"]


class WorkflowNodeFieldOption(BaseModel):
    value: str | int | float | bool
    label: str


class WorkflowNodeFieldDefinition(BaseModel):
    key: str
    label: str
    type: FieldType
    description: str = ""
    section: str = "General"
    default: Any = None
    min: float | None = None
    max: float | None = None
    step: float | None = None
    unit: str | None = None
    options: list[WorkflowNodeFieldOption] = []


class WorkflowNodeDefinition(BaseModel):
    step: str
    label: str
    category: StepCategory
    description: str
    node_type: str
    icon: str
    defaults: dict[str, Any] = {}
    fields: list[WorkflowNodeFieldDefinition] = []
    execution_kind: ExecutionKind = "native"
    legacy_compatible: bool = True


def _field(
    key: str,
    label: str,
    field_type: FieldType,
    *,
    description: str = "",
    section: str = "General",
    default: Any = None,
    min: float | None = None,
    max: float | None = None,
    step: float | None = None,
    unit: str | None = None,
    options: list[tuple[str | int | float | bool, str]] | None = None,
) -> WorkflowNodeFieldDefinition:
    return WorkflowNodeFieldDefinition(
        key=key,
        label=label,
        type=field_type,
        description=description,
        section=section,
        default=default,
        min=min,
        max=max,
        step=step,
        unit=unit,
        options=[
            WorkflowNodeFieldOption(value=value, label=option_label)
            for value, option_label in (options or [])
        ],
    )


def _definition(
    step: StepName,
    label: str,
    category: StepCategory,
    description: str,
    *,
    node_type: str,
    icon: str,
    defaults: dict[str, Any] | None = None,
    fields: list[WorkflowNodeFieldDefinition] | None = None,
    execution_kind: ExecutionKind = "native",
) -> WorkflowNodeDefinition:
    return WorkflowNodeDefinition(
        step=step.value,
        label=label,
        category=category,
        description=description,
        node_type=node_type,
        icon=icon,
        defaults=defaults or {},
        fields=fields or [],
        execution_kind=execution_kind,
    )


_NODE_DEFINITIONS: list[WorkflowNodeDefinition] = [
    _definition(
        StepName.RESOLVE_STEP_PATH,
        "Resolve STEP Path",
        "input",
        "Locate the STEP file on disk from the CAD file record.",
        node_type="inputNode",
        icon="file-up",
        execution_kind="bridge",
    ),
    _definition(
        StepName.OCC_OBJECT_EXTRACT,
        "Extract STEP Objects",
        "processing",
        "Extract part objects and metadata from the STEP file via OCC/cadquery.",
        node_type="processNode",
        icon="layers",
        execution_kind="bridge",
    ),
    _definition(
        StepName.OCC_GLB_EXPORT,
        "Export GLB",
        "processing",
        "Convert STEP geometry into GLB for previews and downstream rendering.",
        node_type="processNode",
        icon="refresh-cw",
        execution_kind="bridge",
    ),
    _definition(
        StepName.GLB_BBOX,
        "Compute Bounding Box",
        "processing",
        "Compute the model bounding box from the exported GLB for framing decisions.",
        node_type="processNode",
        icon="layers",
        execution_kind="bridge",
    ),
    _definition(
        StepName.MATERIAL_MAP_RESOLVE,
        "Resolve Material Map",
        "processing",
        "Map raw part material names to HartOMat material records via aliases.",
        node_type="processNode",
        icon="layers",
        execution_kind="bridge",
    ),
    _definition(
        StepName.AUTO_POPULATE_MATERIALS,
        "Auto Populate Materials",
        "processing",
        "Create missing material records for newly discovered part materials.",
        node_type="processNode",
        icon="layers",
        execution_kind="bridge",
    ),
    _definition(
        StepName.BLENDER_RENDER,
        "Render Thumbnail (Blender)",
        "rendering",
        "Render a thumbnail image with Blender.",
        node_type="renderNode",
        icon="camera",
        defaults={"render_engine": "cycles", "samples": 64, "width": 512, "height": 512},
        fields=[
            _field(
                "render_engine",
                "Render Engine",
                "select",
                description="Renderer backend for this Blender job.",
                section="Render",
                default="cycles",
                options=[("cycles", "Cycles"), ("eevee", "EEVEE")],
            ),
            _field(
                "samples",
                "Samples",
                "number",
                description="Quality samples for the render.",
                section="Render",
                default=64,
                min=1,
                max=4096,
                step=1,
            ),
            _field("width", "Width", "number", section="Output", default=512, min=64, max=8192, step=1, unit="px"),
            _field("height", "Height", "number", section="Output", default=512, min=64, max=8192, step=1, unit="px"),
        ],
    ),
    _definition(
        StepName.THREEJS_RENDER,
        "Render Thumbnail (Three.js)",
        "rendering",
        "Render a thumbnail image with the headless Three.js renderer.",
        node_type="renderNode",
        icon="camera",
        defaults={"width": 512, "height": 512, "transparent_bg": True},
        fields=[
            _field("width", "Width", "number", section="Output", default=512, min=64, max=8192, step=1, unit="px"),
            _field("height", "Height", "number", section="Output", default=512, min=64, max=8192, step=1, unit="px"),
            _field(
                "transparent_bg",
                "Transparent Background",
                "boolean",
                description="Render with alpha channel instead of an opaque background.",
                section="Output",
                default=True,
            ),
        ],
        execution_kind="bridge",
    ),
    _definition(
        StepName.THUMBNAIL_SAVE,
        "Save Thumbnail",
        "output",
        "Persist the generated thumbnail back onto the CAD file record.",
        node_type="outputNode",
        icon="download",
        execution_kind="bridge",
    ),
    _definition(
        StepName.ORDER_LINE_SETUP,
        "Order Line Setup",
        "processing",
        "Validate order-line inputs and prepare the render job context.",
        node_type="processNode",
        icon="layers",
        execution_kind="bridge",
    ),
    _definition(
        StepName.RESOLVE_TEMPLATE,
        "Resolve Template",
        "processing",
        "Resolve the render template for the order line and output type.",
        node_type="processNode",
        icon="layers",
        execution_kind="bridge",
    ),
    _definition(
        StepName.BLENDER_STILL,
        "Render Still",
        "rendering",
        "Render a production still image with Blender.",
        node_type="renderNode",
        icon="camera",
        defaults={"render_engine": "cycles", "samples": 256, "width": 2048, "height": 2048, "rotation_z": 0},
        fields=[
            _field(
                "render_engine",
                "Render Engine",
                "select",
                description="Renderer backend for the still render.",
                section="Render",
                default="cycles",
                options=[("cycles", "Cycles"), ("eevee", "EEVEE")],
            ),
            _field(
                "samples",
                "Samples",
                "number",
                description="Quality samples for the still render.",
                section="Render",
                default=256,
                min=1,
                max=4096,
                step=1,
            ),
            _field("width", "Width", "number", section="Output", default=2048, min=64, max=8192, step=1, unit="px"),
            _field("height", "Height", "number", section="Output", default=2048, min=64, max=8192, step=1, unit="px"),
            _field(
                "rotation_z",
                "Rotation Z",
                "number",
                description="Additional Z-axis rotation in degrees.",
                section="Camera",
                default=0,
                min=-360,
                max=360,
                step=1,
                unit="deg",
            ),
        ],
    ),
    _definition(
        StepName.BLENDER_TURNTABLE,
        "Render Turntable",
        "rendering",
        "Render an animated turntable sequence with Blender.",
        node_type="renderFramesNode",
        icon="film",
        defaults={
            "render_engine": "cycles",
            "samples": 64,
            "width": 2048,
            "height": 2048,
            "fps": 24,
            "duration_s": 5,
            "rotation_z": 0,
        },
        fields=[
            _field(
                "render_engine",
                "Render Engine",
                "select",
                description="Renderer backend for the turntable job.",
                section="Render",
                default="cycles",
                options=[("cycles", "Cycles"), ("eevee", "EEVEE")],
            ),
            _field(
                "samples",
                "Samples",
                "number",
                description="Quality samples for each frame.",
                section="Render",
                default=64,
                min=1,
                max=4096,
                step=1,
            ),
            _field("width", "Width", "number", section="Output", default=2048, min=64, max=8192, step=1, unit="px"),
            _field("height", "Height", "number", section="Output", default=2048, min=64, max=8192, step=1, unit="px"),
            _field("fps", "FPS", "number", section="Animation", default=24, min=1, max=120, step=1),
            _field(
                "duration_s",
                "Duration",
                "number",
                description="Length of the animation clip.",
                section="Animation",
                default=5,
                min=1,
                max=120,
                step=1,
                unit="s",
            ),
            _field(
                "rotation_z",
                "Rotation Z",
                "number",
                description="Base Z-axis rotation before the turntable motion is applied.",
                section="Camera",
                default=0,
                min=-360,
                max=360,
                step=1,
                unit="deg",
            ),
        ],
    ),
    _definition(
        StepName.OUTPUT_SAVE,
        "Save Output",
        "output",
        "Persist the rendered output file and create the media record.",
        node_type="outputNode",
        icon="download",
        execution_kind="bridge",
    ),
    _definition(
        StepName.EXPORT_BLEND,
        "Export Blend",
        "output",
        "Persist the generated .blend file as a downloadable media asset.",
        node_type="outputNode",
        icon="download",
        execution_kind="bridge",
    ),
    _definition(
        StepName.STL_CACHE_GENERATE,
        "Generate STL Cache",
        "processing",
        "Generate and cache STL derivatives next to the STEP source.",
        node_type="convertNode",
        icon="refresh-cw",
        execution_kind="bridge",
    ),
    _definition(
        StepName.NOTIFY,
        "Notify",
        "output",
        "Emit a user-visible notification for workflow completion or failure.",
        node_type="outputNode",
        icon="bell",
        defaults={"channel": "audit_log"},
        fields=[
            _field(
                "channel",
                "Channel",
                "select",
                description="Notification target channel.",
                section="Notification",
                default="audit_log",
                options=[("audit_log", "Audit Log")],
            ),
        ],
        execution_kind="bridge",
    ),
]


_NODE_DEFINITION_BY_STEP = {definition.step: definition for definition in _NODE_DEFINITIONS}


def list_node_definitions() -> list[WorkflowNodeDefinition]:
    return list(_NODE_DEFINITIONS)


def get_node_definition(step: StepName | str) -> WorkflowNodeDefinition | None:
    step_value = step.value if isinstance(step, StepName) else step
    return _NODE_DEFINITION_BY_STEP.get(step_value)


def get_node_type_for_step(step: StepName | str) -> str | None:
    definition = get_node_definition(step)
    return definition.node_type if definition else None