/*
 * Copyright (c) 2022 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { GsonIterator } from './lang/gsonIterator';
import { arrayRemove } from './utils';
import { JsonPrimitive } from './jsonPrimitive';
import { JsonNull } from './jsonNull';
import { JsonElement } from './jsonElement'

export class JsonArray extends JsonElement {
  private elements: Array<JsonElement> = new Array<JsonElement>()

  constructor() {
    super();
  };

  public deepCopy(): JsonArray {
    if (this.elements != null && this.elements.length > 0) {
      let result: JsonArray = new JsonArray();
      for (let element of this.elements) {
        result.add(element);
      }
      return result;
    }
    return new JsonArray();
  }

  public add(value: JsonElement | string | number | boolean): void {
    if (value === null || value === undefined) {
      value = JsonNull.INSTANCE;
      this.elements.push(value);
    } else if (value instanceof JsonElement) {
      this.elements.push(value);
    } else {
      this.elements.push(new JsonPrimitive(value));
    }
  }

  public addAll(array: JsonArray): void {
    for (let element of array.elements) {
      this.elements.push(element);
    }
  }

  public set(index: number, element: JsonElement): JsonElement {
    return this.elements[index] = element;
  }

  public remove(elementOrIndex: JsonElement | number): boolean | JsonElement {
    if (elementOrIndex instanceof JsonElement) {
      return arrayRemove(this.elements, elementOrIndex);
    } else if (this.elements.length > elementOrIndex) {
      let result = this.elements[elementOrIndex]
      this.elements.slice(elementOrIndex, 1);
      return result;
    }
    return null;
  }

  public contains(element: JsonElement): boolean {
    return this.elements.indexOf(element) != -1;
  }

  public size(): number {
    return this.elements.length;
  }

  public isEmpty(): boolean {
    return this.elements == null || this.elements.length === 0;
  }

  public iterator(): IterableIterator<JsonElement> {
    return this.elements.values();
  }

  public list(): GsonIterator<JsonElement> {
    return new GsonIterator(this.elements);
  }

  public get(i: number): JsonElement {
    if (this.elements.length > i) {
      this.elements[i];
    } else {
      return null;
    }
  }

  public getAsNumber(): number {
    if (this.elements.length === 1) {
      let element = this.elements[0];
      if (element instanceof JsonPrimitive) {
        return element.getAsNumber();
      }
    }
    throw new Error('not a number');
  }

  public getAsString(): string {
    if (this.elements.length === 1) {
      let element = this.elements[0];
      if (element instanceof JsonPrimitive) {
        return element.getAsString();
      }
    }
    throw new Error('not a number');
  }

  public getAsBoolean(): boolean {
    if (this.elements.length === 1) {
      let element = this.elements[0];
      if (element instanceof JsonPrimitive) {
        return element.getAsBoolean();
      }
    }
    throw new Error('not a number');
  }
}