// SPDX-License-Identifier: Apache-2.0
// Copyright (c) 2018 Georgi Marinov
//
// 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 { Injectable } from '@angular/core';

import { ToggleKind } from '../../enums/toggle-kind.enum';
import { TruncatorKind } from '../../enums/truncator-kind.enum';

import { ToggleService } from '../../services/toggle/toggle.service';
import { PersistenceService } from '../persistence/persistence.service';
import { StringExService } from '../string-ex/string-ex.service';

/**
 * A truncator service.
 */
@Injectable({
  providedIn: 'root'
})
export class TruncatorService {
  /** Focus threshold feature getter. */
  public get focusThreshold() {
    return {
      /** Truncator kind. */
      truncatorKind: this.truncatorKind,
      /** Default. */
      default: [20, 30, 5][this.truncatorKind],
      // /** Persistence name getter. */
      get persistenceName() { return `${TruncatorKind[this.truncatorKind]}${this.propertyName}`; },
      /** Focus threshold display value. */
      get displayValue() { return ToggleService.displayValues.get(ToggleKind.FocusThreshold) ?? ''; },
      /** Focus threshold property name. */
      get propertyName() { return StringExService.toPascalCase(this.displayValue); },
    };
  }

  /** Tag cloud emphasis feature getter. */
  public get tagCloudEmphasis() {
    return {
      /** Truncator kind. */
      truncatorKind: this.truncatorKind,
      // /** Persistence name getter. */
      // get persistenceName() { return `${TruncatorKind[this.truncatorKind].toUpperCase()} ${this.displayValue}`; },
      get persistenceName() { return `${TruncatorKind[this.truncatorKind]}${this.propertyName}`; },
      /** Tag cloud emphasis display value. */
      get displayValue() { return ToggleService.displayValues.get(ToggleKind.TagCloudEmphasis) ?? ''; },
      /** Focus threshold property name. */
      get propertyName() { return StringExService.toPascalCase(this.displayValue); },
    };
  }

  /** Truncator kind. */
  public truncatorKind = 0 as TruncatorKind;

  /** Focus threshold getter. */
  public get FocusThreshold() {
    const focusThresholdDefault = this.persistenceService.getItem(this.focusThreshold.persistenceName)
      ?? this.focusThreshold.default.toString();
    return Number.parseInt(focusThresholdDefault, 10);
  }
  /** Focus threshold setter. */
  public set FocusThreshold(value) {
    this.persistenceService.setItem(this.focusThreshold.persistenceName, value.toString());
  }

  /** Tag cloud emphasis getter. */
  public get TagCloudEmphasis() {
    return this.persistenceService.getItem(this.tagCloudEmphasis.persistenceName) === 'true';
  }
  /** Tag cloud emphasis setter. */
  public set TagCloudEmphasis(value) {
    this.persistenceService.setItem(this.tagCloudEmphasis.persistenceName, value.toString());
  }

  /**
   * Constructs the Truncator service.
   * ~constructor
   *
   * @param persistenceService The persistence service injected dependency.
   */
  constructor(
    public readonly persistenceService: PersistenceService,
  ) {
  }

  /**
   * Truncated collection.
   *
   * @param collection The collection to process.
   *
   * @returns The truncated collection.
   */
  public truncated(collection: any[]): any[] {
    return collection ? collection.slice(0, this.FocusThreshold) : [];
  }

  /**
   * Remaining collection.
   *
   * @param collection The collection to process.
   *
   * @returns The remaining collection.
   */
  public remaining(collection: any[]): any[] {
    return collection ? collection.slice(this.FocusThreshold) : [];
  }

  /**
   * Remaining collection length.
   *
   * @param collection The collection to process.
   *
   * @returns The remaining collection length.
   */
  public remainingLength(collection: any[]): number {
    return collection ? collection.length - this.FocusThreshold : 0;
  }

  /** Template model value setter function. */
  public modelChange(propertyName: string, value: any) {
    (this as any)[propertyName] = value;
  }
}