import {
  type AnyNode,
  getScaledDimensions,
  type HandleDescriptor,
  type ItemNode as ItemNodeType,
  type NodeDefinition,
} from '@pascal-app/core'
import { buildItemFloorplan } from './floorplan'
import { itemFloorplanMoveTarget } from './floorplan-move'
import { itemPaint } from './paint'
import { itemParametrics } from './parametrics'
import { ItemNode } from './schema'

// The two floor gizmos flank the item at mid-height so they never overlap,
// even on small items: move sits past the left edge, rotate past the right
// edge, both floated the same distance in front of the item. Mirrors the
// wall-item layout below (WALL_SIDE_OFFSET / WALL_GIZMO_LIFT). The guide ring
// traces a circle slightly outside the footprint's bounding circle.
const GIZMO_SIDE_OFFSET = 0.3
const GIZMO_FRONT_OFFSET = 0.3
const ROTATE_RING_OFFSET = 0.06

// Whole-item rotation handle — the two-headed curved arrow. `arc-resize`
// does the angular drag math (raycasts a horizontal plane at the gizmo's
// Y, measures cursor bearing around the item's local origin, returns the
// delta). Rotation snaps to 15° increments by default; holding Shift
// bypasses that snap (handled generically in node-arrow-handles for any
// `shape: 'rotate'`), matching the R/T rotate step for placed items. Item
// rotation is stored as `[x, y, z]`; only the Y component turns.
function itemRotateHandle(): HandleDescriptor<ItemNodeType> {
  return {
    kind: 'arc-resize',
    axis: 'angular',
    shape: 'rotate',
    // Negate the cursor delta to match three.js Y-rotation handedness
    // (positive Ry takes +X → −Z, while atan2(z, x) increases +X → +Z).
    apply: (initial, delta) => {
      const [rx, ry, rz] = initial.rotation ?? [0, 0, 0]
      return { rotation: [rx, ry - delta, rz] }
    },
    placement: {
      // Past the item's right edge at mid-height, floated in front. The
      // registered item mesh carries position + rotation only (scale lives on
      // an inner mesh), so the scaled footprint maps straight to world.
      position: (n) => {
        const [w, h, d] = getScaledDimensions(n)
        return [w / 2 + GIZMO_SIDE_OFFSET, h / 2, d / 2 + GIZMO_FRONT_OFFSET]
      },
      // Fixed −45° tilt leans the curve toward the item's front face.
      rotationY: () => -Math.PI / 4,
    },
    decoration: {
      kind: 'ring',
      radius: (n) => {
        const [w, , d] = getScaledDimensions(n)
        return Math.hypot(w / 2, d / 2) + ROTATE_RING_OFFSET
      },
      y: (n) => getScaledDimensions(n)[1] / 2,
    },
  }
}

// The 4-way move cross, just past the item's left edge. Press-drag hands the
// item to its placement coordinator (showing the bounding box, dimension labels
// and grid-snap ticker) and commits on release — press-drag-release motion with
// the full placement feedback.
function itemMoveHandle(): HandleDescriptor<ItemNodeType> {
  return {
    kind: 'tap-action',
    shape: 'move-cross',
    cursor: 'move',
    onActivate: (node, _scene, editor) => editor.engageMoveDrag(node),
    placement: {
      // Past the item's left edge at mid-height, mirroring the rotate grip on
      // the right so the two never overlap on small items.
      position: (n) => {
        const [w, h, d] = getScaledDimensions(n)
        return [-(w / 2 + GIZMO_SIDE_OFFSET), h / 2, d / 2 + GIZMO_FRONT_OFFSET]
      },
    },
  }
}

// ---- Wall-mounted items (attachTo 'wall' / 'wall-side') ----
// These live in the wall's local frame: position is [along-wall, up, depth]
// and the item faces along the wall normal (its local +Z). Both gizmos use
// `portal: 'grandparent'` so they render in the wall frame like door / window
// handles, and sit a little off the wall surface (+Z) so they're grabbable.

// How far off the wall surface (along the normal) the wall gizmos float, and
// how far to either side of the item they sit.
const WALL_GIZMO_LIFT = 0.12
const WALL_SIDE_OFFSET = 0.3

// Spin the item flat against the wall — rotation about its local +Z (the wall
// normal), written to rotation[2]. Sits just past the item's right edge.
function itemWallRotateHandle(): HandleDescriptor<ItemNodeType> {
  return {
    kind: 'arc-resize',
    axis: 'angular',
    shape: 'rotate',
    rotationPlane: 'node-normal',
    portal: 'grandparent',
    apply: (initial, delta) => {
      const [rx, ry, rz] = initial.rotation ?? [0, 0, 0]
      return { rotation: [rx, ry, rz + delta] }
    },
    placement: {
      position: (n) => {
        const [w] = getScaledDimensions(n)
        return [w / 2 + WALL_SIDE_OFFSET, 0, WALL_GIZMO_LIFT]
      },
    },
  }
}

// Move cross past the item's left edge on the wall face. Tap to hand the item
// to its placement coordinator (`engageMove`) — same feedback as the floating
// move button, and the coordinator handles the wall ↔ floor ↔ ceiling
// transitions the generic translate drag couldn't. `plane: 'node-normal'`
// stands the cross up against the wall face.
function itemWallMoveHandle(): HandleDescriptor<ItemNodeType> {
  return {
    kind: 'tap-action',
    shape: 'move-cross',
    plane: 'node-normal',
    portal: 'grandparent',
    cursor: 'move',
    onActivate: (node, _scene, editor) => editor.engageMoveDrag(node),
    placement: {
      position: (n) => {
        const [w] = getScaledDimensions(n)
        return [-(w / 2 + WALL_SIDE_OFFSET), 0, WALL_GIZMO_LIFT]
      },
    },
  }
}

/**
 * Item — Phase 5 batch kind. Catalog-backed, GLB-rendered, multi-host.
 *
 * Demonstrates the **custom `def.renderer` escape hatch** (see
 * plans/editor-node-registry.md): items use `useGLTF` from drei to
 * load CDN assets, plus a non-trivial interactive-widget layer inside
 * the rendered scene. Not expressible as a pure `def.geometry`. The
 * registry mounts the custom React renderer as-is.
 *
 * Capabilities:
 *  - **No `movable`**: item's move is bespoke `MoveItemContent` —
 *    handles attachTo transitions mid-drag (floor ↔ wall ↔ ceiling),
 *    asset.attachTo lookups, scale-preserving Y math for surface
 *    placement. The smooth generic mover can't express that. Legacy
 *    mover keeps running via capability-driven dispatch.
 *  - `selectable`, `duplicable`, `deletable` standard.
 *
 * Stages:
 *  - A: registered.
 *  - B: N/A — def.renderer escape hatch (GLB / useGLTF).
 *  - C: `def.floorplan` resolves parent chain via `ctx.resolve`,
 *    returns a rotated rectangle (width × depth). Mirrors the legacy
 *    `getItemFloorplanTransform` math. Legacy `floorplanItemEntries`
 *    short-circuits when item is registered.
 *
 * `toolHints`: matches the legacy ItemHelper UI (mouse / R / T / Shift /
 * Esc) — registry-driven placement panel.
 */
export const itemDefinition: NodeDefinition<typeof ItemNode> = {
  kind: 'item',
  schemaVersion: 1,
  schema: ItemNode,
  category: 'furnish',
  surfaceRole: 'furnishing',

  // Defaults shape is cast: the schema requires a fully-typed `asset`
  // field, but in practice items are always created from the catalog
  // (the asset is supplied at placement time). `createNode` re-parses
  // through the schema, so any missing zod defaults fill at runtime.
  defaults: () =>
    ({
      object: 'node',
      parentId: null,
      visible: true,
      metadata: {},
      children: [],
      position: [0, 0, 0],
      rotation: [0, 0, 0],
      scale: [1, 1, 1],
      asset: {
        id: 'placeholder',
        category: 'misc',
        name: 'Item',
        thumbnail: '',
        src: 'asset:placeholder',
        dimensions: [1, 1, 1],
        source: 'library',
      },
    }) as unknown as Omit<ItemNodeType, 'id' | 'type'>,

  capabilities: {
    selectable: { hitVolume: 'bbox' },
    duplicable: true,
    deletable: true,
    paint: itemPaint,
    // Items participate in compositions — e.g. "table-with-plants",
    // "shelf-with-books-on-top" — so they're presettable in their own
    // right (and as descendants of presettable parents). The GLB-kind
    // catalog still exists alongside; preset-flavoured items become
    // siblings of GLB items inside the unified `items` table.
    //
    // Items can be hosted on walls (assets with `attachTo: 'wall'`)
    // via `wallId` + `wallT`, or on a roof-segment wall face via
    // `roofSegmentId`. When a composition that includes a wall-hosted
    // item is saved as a preset (a sconce, a hanging shelf, etc.), the
    // host app strips these via `getHostRefFields(def)` so the
    // descendant re-attaches against the new host geometry at
    // placement time.
    hostRefFields: ['wallId', 'wallT', 'roofSegmentId', 'roofFace'],
    // Floor items get lifted by slabs underneath via the generic
    // `<FloorElevationSystem>`. Wall- / ceiling-attached items live in
    // their parent's local frame and skip the lift via `applies`.
    floorPlaced: {
      footprint: (node) => {
        const item = node as ItemNodeType
        return { dimensions: getScaledDimensions(item), rotation: item.rotation }
      },
      applies: (node) => !(node as ItemNodeType).asset.attachTo,
    },
    // Recessed ceiling fixtures cut a hole in their host ceiling. The viewer's
    // CeilingSystem queries this capability on each child of a ceiling so it
    // never needs to branch on `node.type`.
    ceilingCut: {
      buildCeilingHole(rawNode: AnyNode): Array<[number, number]> | null {
        const node = rawNode as ItemNodeType
        if (!node.asset.recessed || node.asset.attachTo !== 'ceiling') return null

        // Inset slightly so the fixture's trim (widest part, sitting in the
        // ceiling plane) overlaps the solid ceiling around the opening and hides
        // the cut edge. Same constant the old ceiling-system used.
        const INSET = 0.82
        const [width, , depth] = getScaledDimensions(node)
        const halfW = (width / 2) * INSET
        const halfD = (depth / 2) * INSET
        const cx = node.position[0]
        const cz = node.position[2]
        const yaw = node.rotation?.[1] ?? 0
        const cos = Math.cos(yaw)
        const sin = Math.sin(yaw)

        // Rotate the (inset) footprint corners about Y and translate to the
        // item's plan position. Y-rotation of (dx, dz): (dx·cos + dz·sin, −dx·sin + dz·cos).
        return (
          [
            [-halfW, -halfD],
            [halfW, -halfD],
            [halfW, halfD],
            [-halfW, halfD],
          ] as Array<[number, number]>
        ).map(([dx, dz]) => [cx + dx * cos + dz * sin, cz - dx * sin + dz * cos])
      },
    },
  },

  parametrics: itemParametrics,

  // In-world rotate + move gizmos for selected items.
  //  - Floor items: world-Y rotate + free floor-plane move cross.
  //  - Wall items: wall-normal rotate (spin flat against the wall) + a move
  //    cross constrained to the wall face. Both ride the wall frame.
  //  - Ceiling items: no gizmos yet (move via the move tool).
  handles: (node) => {
    const attachTo = (node as ItemNodeType).asset.attachTo
    if (attachTo === 'wall' || attachTo === 'wall-side') {
      return [itemWallRotateHandle(), itemWallMoveHandle()]
    }
    if (attachTo) return []
    return [itemRotateHandle(), itemMoveHandle()]
  },

  renderer: {
    kind: 'parametric',
    module: () => import('./renderer'),
  },
  system: {
    module: () => import('./system'),
    // Same priority as the legacy ItemSystem.
    priority: 2,
  },
  // Catalog placement tool — mounted when `useEditor.tool === 'item'`.
  // Wraps the same placement coordinator the move-tool uses (surface
  // strategies for floor / wall / ceiling / item-surface). Replaces
  // the legacy `editor/src/components/tools/item/item-tool.tsx`.
  tool: () => import('./tool'),

  // Stage D — 3D move-tool (registry-driven). Adopts the moving node
  // and runs the placement coordinator with surface strategies for
  // floor / wall / ceiling / item-surface, including attachTo
  // *transitions* (drop a wall item on a ceiling and have it switch).
  // Replaces the legacy `MoveItemContent` in editor's dispatcher; the
  // `getRegistryAffordanceTool('item', 'move')` lookup picks this up.
  affordanceTools: {
    move: () => import('./move-tool'),
  },

  // Stage C: floor-plan polygon. ctx.resolve walks the parent chain
  // (wall / nested item / level) to compute the world-space transform.
  floorplan: buildItemFloorplan,
  // 2D move-on-floorplan handler. Branches on `asset.attachTo`:
  // wall items snap to walls (like door / window), ceiling items
  // snap to ceiling polygons, floor items snap to slabs. attachTo
  // *transitions* (drop a wall item on a ceiling) remain canonical
  // in the 3D path; 2D only re-anchors within the same family.
  floorplanMoveTarget: itemFloorplanMoveTarget,

  toolHints: [
    { key: 'Left click', label: 'Place item' },
    { key: 'R', label: 'Rotate counterclockwise' },
    { key: 'T', label: 'Rotate clockwise' },
    { key: 'Shift', label: 'Free place' },
    { key: 'Esc', label: 'Cancel' },
  ],

  presentation: {
    label: 'Item',
    description: 'A catalog-backed item (furniture, fixtures, decorations).',
    icon: { kind: 'url', src: '/icons/item.png' },
    paletteSection: 'furnish',
    paletteOrder: 10,
  },

  mcp: {
    description:
      'A catalog-backed item with asset reference, transforms, and optional attachTo for wall/ceiling mounting.',
  },
}