// (C) Copyright 2015 Moodle Pty 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 { Component, Input, OnChanges, SimpleChange, ChangeDetectionStrategy, ElementRef, OnInit } from '@angular/core';
import { SafeStyle } from '@angular/platform-browser';
import { DomSanitizer, Translate } from '@singletons';

/**
 * Component to show a progress bar and its value.
 *
 * Example usage:
 * <core-progress-bar [progress]="percentage"></core-progress-bar>
 */
@Component({
    selector: 'core-progress-bar',
    templateUrl: 'core-progress-bar.html',
    styleUrls: ['progress-bar.scss'],
    changeDetection: ChangeDetectionStrategy.OnPush,
})
export class CoreProgressBarComponent implements OnInit, OnChanges {

    @Input() progress!: number | string; // Percentage from 0 to 100. Negative number will show an indeterminate progress bar.
    @Input() text?: string; // Percentage in text to be shown at the right. If not defined, progress will be used.
    @Input() a11yText?: string; // Accessibility text to read before the percentage.
    @Input() ariaDescribedBy?: string; // ID of the element that described the progress, if any.
    @Input() color = '';

    width?: SafeStyle;
    progressBarValueText?: string;

    protected textSupplied = false;
    protected element: HTMLElement;

    constructor(elementRef: ElementRef) {
        this.element = elementRef.nativeElement;
    }

    /**
     * @inheritdoc
     */
    ngOnInit(): void {
        if (this.color) {
            this.element.classList.add('ion-color', 'ion-color-' + this.color);
        }
    }

    /**
     * @inheritdoc
     */
    ngOnChanges(changes: { [name: string]: SimpleChange }): void {
        if (changes.color) {
            this.element.classList.remove('ion-color', 'ion-color-' + changes.color.previousValue);
            if (changes.color.currentValue) {
                this.element.classList.add('ion-color', 'ion-color-' + changes.color.currentValue);
            }
        }

        if (changes.text && changes.text.currentValue !== undefined) {
            // User provided a custom text, don't use default.
            this.textSupplied = true;
        }

        if (changes.progress) {
            // Progress has changed.
            if (typeof this.progress == 'string') {
                this.progress = parseInt(this.progress, 10);
            }

            if (this.progress < 0 || isNaN(this.progress)) {
                this.progress = -1;
            }

            if (this.progress != -1) {
                // Remove decimals.
                this.progress = Math.floor(this.progress);

                if (!this.textSupplied) {
                    this.text = String(this.progress);
                }

                this.width = DomSanitizer.bypassSecurityTrustStyle(this.progress + '%');
            }
        }

        if (changes.text || changes.progress || changes.a11yText) {
            this.progressBarValueText = (this.a11yText ? Translate.instant(this.a11yText) + ' ' : '') +
                Translate.instant('core.percentagenumber', { $a: this.text });
        }
    }

}