import { History } from './interfaces';

export class HousePlannerCanvasHistory {
  private history: History<unknown>[][] = [];
  private unhistory: History<unknown>[][] = [];
  private lastCommandWasUndo = false;

  constructor() {}

  appendToHistory(changes: History<any>[]) {
    this.history.push(changes);
    this.unhistory.length = 0;
  }

  undo() {
    const lastChanges = this.history.pop();
    if (!lastChanges) return;
    if (!this.lastCommandWasUndo && this.unhistory.length) {
      this.unhistory.length = 0;
    }
    this.lastCommandWasUndo = true;

    let redo = [];
    for (const change of lastChanges) {
      if (!change.object) continue;
      const preChange = (change.object as any)[change.property];
      (change.object as any)[change.property] = change.value;
      redo.push({
        ...change,
        value: preChange as any,
      });
    }
    this.unhistory.push(redo);
  }

  redo() {
    const lastChanges = this.unhistory.pop();
    if (!lastChanges) return;
    this.lastCommandWasUndo = false;
    let undo = [];
    for (const change of lastChanges) {
      if (!change.object) continue;
      const preChange = (change.object as any)[change.property];
      (change.object as any)[change.property] = change.value;
      undo.push({
        ...change,
        value: preChange as any,
      });
    }
    this.history.push(undo);
  }
}