import { Command } from "./Command";
import { findLayerRecursively } from "../utils/layerHelper";
import { fabric } from "fabric-with-all";
import {
  findObjectById,
  generateId,
  insertObjectAtZIndex,
  removeCanvasObjectByObject,
} from "../utils/helper";
import { restoreFabricObject } from "../utils/objectHelper";

/**
 * 填充组图层背景命令
 */
export class FillGroupLayerBackgroundCommand extends Command {
  constructor(options) {
    super({ name: "填充组图层背景", saveState: true });
    this.canvas = options.canvas;
    this.layers = options.layers;
    this.canvasManager = options.canvasManager;
    this.layerId = options.layerId;
    this.fillColor = options.fillColor;
    this.oldFill = null;
    this.oldFillColor = null;
    this.newFill = null;

    const { layer } = findLayerRecursively(this.layers.value, this.layerId);

    this.layer = layer;

    this.group = null;

    this.originalfabricObjects = this._collectOriginalObjects(); // 记录所有的原始对象

    // 计算所有对象的边界
    this.originalInfo = this._getCurrentObjectsBoundingRect();
  }

  async execute() {
    const layer = this.layer;
    if (!layer.isBackground && !layer.isFixed && !layer.fabricObjects?.length) return false;

    this.oldFill = layer.fill ?? null;
    this.oldFillColor = layer.oldFillColor ?? null;

    // 构建填充对象
    let clippingMaskFabricObject = null;
    if (layer.clippingMask) {
      clippingMaskFabricObject = await restoreFabricObject(layer.clippingMask, this.canvas);
      clippingMaskFabricObject.clipPath = null;
      clippingMaskFabricObject.set({ absolutePositioned: true });
      this.newFill = new fabric.Rect({
        width: clippingMaskFabricObject.width,
        height: clippingMaskFabricObject.height,
        left: clippingMaskFabricObject.left || 0,
        top: clippingMaskFabricObject.top || 0,
        fill: this.fillColor,
        layerId: this.layerId,
        id: this.oldFill?.id || generateId("fill-"),
        selectable: false,
        evented: false,
        originX: clippingMaskFabricObject.originX || "center",
        originY: clippingMaskFabricObject.originY || "center",
        scaleX: clippingMaskFabricObject.scaleX || 1,
        scaleY: clippingMaskFabricObject.scaleY || 1,
        // type: "fill",
      });
      this.newFill.clipPath = clippingMaskFabricObject;
      // this.newFill.dirty = true;
      // this.newFill.setCoords();
    } else {
      const originalInfo = this.originalInfo;
      if (originalInfo) {
        this.newFill = new fabric.Rect({
          width: originalInfo.width,
          height: originalInfo.height,
          left: originalInfo.left + originalInfo.width / 2 || 0,
          top: originalInfo.top + originalInfo.height / 2 || 0,
          fill: this.fillColor,
          layerId: this.layerId,
          id: this.oldFill?.id || generateId("fill-"),
          selectable: false,
          evented: false,
          originX: "center",
          originY: "center",
          // type: "fill",
        });
      }
    }

    // 判断fabricObjects是否是组对象
    const firstObj = layer.fabricObjects?.[0];
    const canvasObj = findObjectById(this.canvas, firstObj?.id)?.object;
    if ((canvasObj && canvasObj.type === "group") || canvasObj._objects?.length > 0) {
      this.newFill.set({
        left: 0,
        top: 0,
      });
      // 将新填充对象添加到组的最前面
      // canvasObj._objects.unshift(this.newFill);
      canvasObj.insertAt(this.newFill, 0, false);
      // canvasObj.addWithUpdate();
      canvasObj.setCoords();
      canvasObj.setObjectsCoords();
      // canvasObj.dirty = true; // 标记为脏对象
      // this.canvas.renderAll();
      // this.group = canvasObj;
    } else if (layer.fabricObjects && layer.fabricObjects.length > 0) {
      // 普通对象，组成新组
      const layerObjects = this.canvas.getObjects().filter((obj) => obj.layerId === this.layerId);
      let insertIndex = this.canvas.getObjects()?.findIndex((obj) => obj.id === firstObj?.id) ?? 0;
      insertIndex = insertIndex === -1 ? 0 : insertIndex;

      this.group = new fabric.Group([this.newFill, ...layerObjects]);
      this.group.set({
        id: layerObjects[0]?.id || generateId("group-"),
        layerId: layerObjects[0]?.layerId,
      });
      this.group.setCoords();
      removeCanvasObjectByObject(this.canvas, layerObjects[0]);
      insertObjectAtZIndex(this.canvas, this.group, insertIndex, false);
    }

    // layer.fabricObjects = [this.group?.toObject?.(["id", "layerId"]) || this.group];
    this.canvas.renderAll();
    layer.fill = null; // this.newFill.toObject(["id", "layerId"]);
    layer.fillColor = this.fillColor;
    this.canvasManager.thumbnailManager?.generateLayerThumbnail(this.layer.id);
    return true;
  }
  async undo() {
    this.layer.fillColor = this.oldFillColor;
    this.layer.fill = this.oldFill;

    // 判断fabricObjects是否是组对象
    const firstObj = this.layer.fabricObjects?.[0];
    const canvasObj = this.group || findObjectById(this.canvas, firstObj?.id)?.object;

    if ((canvasObj && canvasObj.type === "group") || canvasObj?._objects?.length > 0) {
      // 移除新添加的填充对象
      if (canvasObj._objects?.[0] === this.newFill) {
        canvasObj._objects.shift();
        canvasObj.addWithUpdate();
        canvasObj.setCoords();
        canvasObj.dirty = true;
      }
      this.canvas.renderAll();
    } else if (this.group) {
      // 如果是新建的group，需要拆分还原
      // 先移除新建的group
      this.canvas.remove(this.group);
      // 重新添加原始对象
      this.originalfabricObjects.forEach((obj) => {
        if (!this.canvas.getObjects().includes(obj)) {
          this.canvas.add(obj);
        }
      });
      this.canvas.renderAll();
      this.group = null;
    }

    this.canvasManager.thumbnailManager?.generateLayerThumbnail(this.layer.id);
    return true;
  }

  _collectOriginalObjects() {
    if (this.layer.children && this.layer.children.length > 0) {
      // 如果是组图层，收集所有子图层的fabric对象
      return this.layer.children
        .flatMap((child) => child.fabricObjects || [])
        .map((obj) => {
          return findObjectById(this.canvas.value, obj.id)?.object || obj;
        });
    } else if (this.layer.fabricObjects && this.layer.fabricObjects.length > 0) {
      // 如果是普通图层，直接返回其fabric对象
      return this.layer.fabricObjects.map((obj) => {
        return findObjectById(this.canvas.value, obj.id)?.object || obj;
      });
    } else {
      // 如果没有fabric对象，返回空数组
      return [];
    }
  }
  // 获取当前所有对象的边界信息
  _getCurrentObjectsBoundingRect() {
    // this.originalfabricObjects = this._collectOriginalObjects();
    let minLeft = Infinity,
      minTop = Infinity,
      maxRight = -Infinity,
      maxBottom = -Infinity;
    console.log("计算当前所有对象的边界信息:===>", this.originalfabricObjects.length);
    this.originalfabricObjects?.forEach((obj) => {
      const { object } = findObjectById(this.canvas, obj.id) || {};
      if (object) {
        const rect = object.getBoundingRect({ absolute: true, includeStroke: false });
        minLeft = Math.min(minLeft, rect.left);
        minTop = Math.min(minTop, rect.top);
        maxRight = Math.max(maxRight, rect.left + rect.width);
        maxBottom = Math.max(maxBottom, rect.top + rect.height);
      }
    });
    if (minLeft === Infinity || minTop === Infinity) return null;
    return {
      left: minLeft,
      top: minTop,
      width: maxRight - minLeft,
      height: maxBottom - minTop,
    };
  }
}