import { emitter, type GridEvent, useScene, RoofNode, type LevelNode, type AnyNode } from "@pascal-app/core";
import { useViewer } from "@pascal-app/viewer";
import { useEffect, useMemo, useRef, useState } from "react";
import { BufferGeometry, DoubleSide, type Line, Vector3 } from "three";
import useEditor from "@/store/use-editor";

// Default roof dimensions
const DEFAULT_HEIGHT = 1.5;
const PREVIEW_LINE_HEIGHT = 0.03; // Very thin preview

/**
 * Creates a roof with the given corners
 */
const commitRoofPlacement = (
  levelId: LevelNode["id"],
  corner1: [number, number, number],
  corner2: [number, number, number]
): RoofNode["id"] => {
  const { createNode, nodes } = useScene.getState();

  // Calculate center position and dimensions from corners
  const centerX = (corner1[0] + corner2[0]) / 2;
  const centerZ = (corner1[2] + corner2[2]) / 2;

  const length = Math.abs(corner2[0] - corner1[0]);
  const width = Math.abs(corner2[2] - corner1[2]);

  // Split width evenly between left and right slopes
  const slopeWidth = Math.max(width / 2, 0.5);

  // Count existing roofs for naming
  const roofCount = Object.values(nodes).filter((n) => n.type === "roof").length;
  const name = `Roof ${roofCount + 1}`;

  const roof = RoofNode.parse({
    name,
    position: [centerX, 0, centerZ], // Y is always 0
    length: Math.max(length, 0.5),
    height: DEFAULT_HEIGHT,
    leftWidth: slopeWidth,
    rightWidth: slopeWidth,
  });

  createNode(roof, levelId);
  return roof.id;
};

type PreviewState = {
  corner1: [number, number, number] | null;
  cursorPosition: [number, number, number];
  levelY: number;
};

export const RoofTool: React.FC = () => {
  const outlineRef = useRef<Line>(null!);
  const currentLevelId = useViewer((state) => state.selection.levelId);
  const setSelection = useViewer((state) => state.setSelection);
  const setTool = useEditor((state) => state.setTool);
  const setMode = useEditor((state) => state.setMode);

  const corner1Ref = useRef<[number, number, number] | null>(null);
  const [preview, setPreview] = useState<PreviewState>({
    corner1: null,
    cursorPosition: [0, 0, 0],
    levelY: 0,
  });

  useEffect(() => {
    if (!currentLevelId) return;

    // Initialize outline geometry
    outlineRef.current.geometry = new BufferGeometry();

    const updateOutline = (corner1: [number, number, number], corner2: [number, number, number]) => {
      const y = corner1[1] + PREVIEW_LINE_HEIGHT;
      const points = [
        new Vector3(corner1[0], y, corner1[2]),
        new Vector3(corner2[0], y, corner1[2]),
        new Vector3(corner2[0], y, corner2[2]),
        new Vector3(corner1[0], y, corner2[2]),
        new Vector3(corner1[0], y, corner1[2]), // Close the loop
      ];
      outlineRef.current.geometry.dispose();
      outlineRef.current.geometry = new BufferGeometry().setFromPoints(points);
      outlineRef.current.visible = true;
    };

    const onGridMove = (event: GridEvent) => {
      // Snap to 0.5 grid
      const gridX = Math.round(event.position[0] * 2) / 2;
      const gridZ = Math.round(event.position[2] * 2) / 2;
      const y = event.position[1];

      const cursorPosition: [number, number, number] = [gridX, y, gridZ];

      setPreview({
        corner1: corner1Ref.current,
        cursorPosition,
        levelY: y,
      });

      // Update outline if we have first corner
      if (corner1Ref.current) {
        updateOutline(corner1Ref.current, cursorPosition);
      }
    };

    const onGridClick = (event: GridEvent) => {
      if (!currentLevelId) return;

      const gridX = Math.round(event.position[0] * 2) / 2;
      const gridZ = Math.round(event.position[2] * 2) / 2;
      const y = event.position[1];

      if (!corner1Ref.current) {
        // First click - set corner 1
        corner1Ref.current = [gridX, y, gridZ];
        setPreview((prev) => ({
          ...prev,
          corner1: corner1Ref.current,
        }));
      } else {
        // Second click - create the roof
        const roofId = commitRoofPlacement(
          currentLevelId,
          corner1Ref.current,
          [gridX, y, gridZ]
        );

        // Auto-select the newly created roof
        setSelection({ selectedIds: [roofId as AnyNode["id"]] });

        // Reset state
        corner1Ref.current = null;
        outlineRef.current.visible = false;

        // Switch to select mode and deactivate tool
        setMode('select');
        setTool(null);
      }
    };

    // Subscribe to events
    emitter.on("grid:move", onGridMove);
    emitter.on("grid:click", onGridClick);

    return () => {
      emitter.off("grid:move", onGridMove);
      emitter.off("grid:click", onGridClick);

      // Reset state on unmount
      corner1Ref.current = null;
    };
  }, [currentLevelId, setTool, setSelection, setMode]);

  const { corner1, cursorPosition, levelY } = preview;

  // Calculate preview dimensions for display
  const previewDimensions = useMemo(() => {
    if (!corner1) return null;
    const length = Math.abs(cursorPosition[0] - corner1[0]);
    const width = Math.abs(cursorPosition[2] - corner1[2]);
    const centerX = (corner1[0] + cursorPosition[0]) / 2;
    const centerZ = (corner1[2] + cursorPosition[2]) / 2;
    return { length, width, centerX, centerZ };
  }, [corner1, cursorPosition]);

  return (
    <group>
      {/* Outline showing rectangle being drawn */}
      {/* @ts-ignore */}
      <line ref={outlineRef} frustumCulled={false} renderOrder={1} visible={false}>
        <bufferGeometry />
        <lineBasicNodeMaterial
          color="#8b4513"
          linewidth={2}
          depthTest={false}
          depthWrite={false}
        />
      </line>

      {/* First corner marker */}
      {corner1 && (
        <mesh position={[corner1[0], levelY + 0.02, corner1[2]]} rotation={[-Math.PI / 2, 0, 0]}>
          <ringGeometry args={[0.1, 0.15, 32]} />
          <meshBasicMaterial
            color="#22c55e"
            depthTest={false}
            depthWrite={false}
          />
        </mesh>
      )}

      {/* Cursor marker on ground */}
      <mesh position={[cursorPosition[0], cursorPosition[1] + 0.02, cursorPosition[2]]} rotation={[-Math.PI / 2, 0, 0]}>
        <ringGeometry args={[0.1, 0.15, 32]} />
        <meshBasicMaterial
          color="#8b4513"
          depthTest={false}
          depthWrite={false}
        />
      </mesh>

      {/* Thin preview fill when drawing */}
      {previewDimensions && previewDimensions.length > 0.1 && previewDimensions.width > 0.1 && (
        <mesh
          position={[previewDimensions.centerX, levelY + 0.01, previewDimensions.centerZ]}
          rotation={[-Math.PI / 2, 0, 0]}
        >
          <planeGeometry args={[previewDimensions.length, previewDimensions.width]} />
          <meshBasicMaterial
            color="#8b4513"
            opacity={0.2}
            transparent
            side={DoubleSide}
            depthTest={false}
            depthWrite={false}
          />
        </mesh>
      )}
    </group>
  );
};