import { IRelatedQuestionAnswerResponse } from '../../rest/QuestionAnswerResponse';
import { uniqueId } from 'underscore';
import { AccessibleButton } from '../../utils/AccessibleButton';
import { SVGIcons } from '../../utils/SVGIcons';
import { attachShadow } from '../../misc/AttachShadowPolyfill';
import { $$, Dom } from '../../utils/Dom';
import { l } from '../../strings/Strings';
import { IQueryResult } from '../../rest/QueryResult';
import {
  analyticsActionCauseList,
  IAnalyticsSmartSnippetSuggestionMeta,
  IAnalyticsSmartSnippetSuggestionOpenSnippetInlineLinkMeta,
  IAnalyticsSmartSnippetSuggestionOpenSourceMeta
} from '../Analytics/AnalyticsActionListMeta';
import { ResultLink } from '../ResultLink/ResultLink';
import { IComponentBindings } from '../Base/ComponentBindings';
import { Utils } from '../../utils/Utils';
import { IFieldOption } from '../Base/IComponentOptions';
import { getSanitizedAnswerSnippet, transformSnippetLinks } from './SmartSnippetCommon';

const QUESTION_CLASSNAME = `coveo-smart-snippet-suggestions-question`;
const QUESTION_TITLE_CLASSNAME = `${QUESTION_CLASSNAME}-title`;
const QUESTION_TITLE_LABEL_CLASSNAME = `${QUESTION_TITLE_CLASSNAME}-label`;
const QUESTION_TITLE_CHECKBOX_CLASSNAME = `${QUESTION_TITLE_CLASSNAME}-checkbox`;
const QUESTION_SNIPPET_CLASSNAME = `${QUESTION_CLASSNAME}-snippet`;
const QUESTION_SNIPPET_CONTAINER_CLASSNAME = `${QUESTION_SNIPPET_CLASSNAME}-container`;
const QUESTION_SNIPPET_HIDDEN_CLASSNAME = `${QUESTION_SNIPPET_CLASSNAME}-hidden`;
const SHADOW_CLASSNAME = `${QUESTION_SNIPPET_CLASSNAME}-content`;
const RAW_CONTENT_CLASSNAME = `${SHADOW_CLASSNAME}-raw`;
const SOURCE_CLASSNAME = `${QUESTION_CLASSNAME}-source`;
const SOURCE_TITLE_CLASSNAME = `${SOURCE_CLASSNAME}-title`;
const SOURCE_URL_CLASSNAME = `${SOURCE_CLASSNAME}-url`;

export const SmartSnippetCollapsibleSuggestionClassNames = {
  QUESTION_CLASSNAME,
  QUESTION_TITLE_CLASSNAME,
  QUESTION_TITLE_LABEL_CLASSNAME,
  QUESTION_TITLE_CHECKBOX_CLASSNAME,
  QUESTION_SNIPPET_CLASSNAME,
  QUESTION_SNIPPET_CONTAINER_CLASSNAME,
  QUESTION_SNIPPET_HIDDEN_CLASSNAME,
  SHADOW_CLASSNAME,
  RAW_CONTENT_CLASSNAME,
  SOURCE_CLASSNAME,
  SOURCE_TITLE_CLASSNAME,
  SOURCE_URL_CLASSNAME
};

export class SmartSnippetCollapsibleSuggestion {
  private readonly labelId = uniqueId(QUESTION_TITLE_LABEL_CLASSNAME);
  private readonly snippetId = uniqueId(QUESTION_SNIPPET_CLASSNAME);
  private readonly checkboxId = uniqueId(QUESTION_TITLE_CHECKBOX_CLASSNAME);
  private contentLoaded: Promise<void>;
  private snippetAndSourceContainer: Dom;
  private collapsibleContainer: Dom;
  private checkbox: Dom;
  private expanded = false;

  constructor(
    private readonly options: {
      readonly questionAnswer: IRelatedQuestionAnswerResponse;
      readonly bindings: IComponentBindings;
      readonly innerCSS: string;
      readonly searchUid: string;
      readonly titleField: IFieldOption;
      readonly hrefTemplate?: string;
      readonly alwaysOpenInNewWindow?: boolean;
      readonly source?: IQueryResult;
      readonly useIFrame?: boolean;
    }
  ) {}

  public get loading() {
    return this.contentLoaded;
  }

  private get analyticsSuggestionMeta(): IAnalyticsSmartSnippetSuggestionMeta {
    const { documentId, question, answerSnippet } = this.options.questionAnswer;
    return {
      searchQueryUid: this.options.searchUid,
      documentId,
      question,
      answerSnippet
    };
  }

  public build() {
    const collapsibleContainer = this.buildCollapsibleContainer(this.options.questionAnswer, this.buildStyle(this.options.innerCSS));
    const title = this.buildTitle(this.options.questionAnswer.question);
    this.updateExpanded();
    return $$(
      'li',
      {
        className: QUESTION_CLASSNAME,
        ariaLabelledby: this.labelId
      },
      title,
      collapsibleContainer
    ).el as HTMLLIElement;
  }

  private buildStyle(innerCSS: string) {
    const styleTag = document.createElement('style');
    styleTag.innerHTML = innerCSS;
    return styleTag;
  }

  private buildTitle(question: string) {
    const checkbox = this.buildCheckbox(question);
    const label = $$('span', { className: QUESTION_TITLE_LABEL_CLASSNAME, id: this.labelId });
    label.text(question);
    const title = $$('span', { className: QUESTION_TITLE_CLASSNAME }, label, checkbox);
    title.on('click', () => this.toggle());
    return title;
  }

  private buildCheckbox(question: string) {
    this.checkbox = $$('div', {
      role: 'button',
      tabindex: 0,
      ariaControls: this.snippetId,
      className: QUESTION_TITLE_CHECKBOX_CLASSNAME,
      id: this.checkboxId
    });
    new AccessibleButton()
      .withElement(this.checkbox)
      .withLabel(l('ExpandQuestionAnswer', question))
      .withEnterKeyboardAction(() => this.toggle())
      .build();
    return this.checkbox;
  }

  private buildCollapsibleContainer(questionAnswer: IRelatedQuestionAnswerResponse, style: HTMLStyleElement) {
    const shadowContainer = $$('div', { className: SHADOW_CLASSNAME });
    this.snippetAndSourceContainer = $$('div', { className: QUESTION_SNIPPET_CONTAINER_CLASSNAME }, shadowContainer);
    this.collapsibleContainer = $$('div', { className: QUESTION_SNIPPET_CLASSNAME, id: this.snippetId }, this.snippetAndSourceContainer);
    this.contentLoaded = attachShadow(shadowContainer.el, {
      mode: 'open',
      title: l('AnswerSpecificSnippet', questionAnswer.question),
      useIFrame: this.options.useIFrame
    }).then(shadowRoot => {
      shadowRoot.appendChild(this.buildAnswerSnippetContent(questionAnswer, style).el);
    });
    if (this.options.source) {
      this.snippetAndSourceContainer.append(this.buildSourceUrl().el);
      this.snippetAndSourceContainer.append(this.buildSourceTitle().el);
    }
    return this.collapsibleContainer;
  }

  private buildAnswerSnippetContent(questionAnswer: IRelatedQuestionAnswerResponse, style: HTMLStyleElement) {
    const snippet = $$('div', { className: RAW_CONTENT_CLASSNAME }, getSanitizedAnswerSnippet(questionAnswer));
    transformSnippetLinks(snippet.el, this.options.alwaysOpenInNewWindow, link => this.sendOpenSnippetLinkAnalytics(link));
    const container = $$('div', {}, snippet);
    container.append(style);
    return container;
  }

  private buildSourceTitle() {
    const link = this.buildLink(SOURCE_TITLE_CLASSNAME);
    link.text(Utils.getFieldValue(this.options.source!, <string>this.options.titleField));
    return link;
  }

  private buildSourceUrl() {
    const link = this.buildLink(SOURCE_URL_CLASSNAME);
    link.text((link.el as HTMLAnchorElement).href);
    return link;
  }

  private buildLink(className: string) {
    const element = $$('a', { className: `CoveoResultLink ${className}` });
    new ResultLink(
      element.el,
      {
        hrefTemplate: this.options.hrefTemplate,
        logAnalytics: href => this.sendOpenSourceAnalytics(element.el, href),
        alwaysOpenInNewWindow: this.options.alwaysOpenInNewWindow
      },
      { ...this.options.bindings, resultElement: this.collapsibleContainer.el },
      this.options.source
    );
    return element;
  }

  private toggle() {
    this.expanded = !this.expanded;
    this.updateExpanded();
    if (this.expanded) {
      this.sendExpandAnalytics();
    } else {
      this.sendCollapseAnalytics();
    }
  }

  private updateIFrameExpanded() {
    const iframe = this.snippetAndSourceContainer.find('iframe');
    if (!iframe) {
      return;
    }
    this.expanded ? iframe.removeAttribute('tabindex') : iframe.setAttribute('tabindex', '-1');
  }

  private updateExpanded() {
    this.checkbox.setAttribute('aria-expanded', this.expanded.toString());
    this.checkbox.setHtml(this.expanded ? SVGIcons.icons.arrowUp : SVGIcons.icons.arrowDown);
    this.collapsibleContainer.setAttribute('aria-hidden', (!this.expanded).toString());
    this.collapsibleContainer.toggleClass(QUESTION_SNIPPET_HIDDEN_CLASSNAME, !this.expanded);
    this.collapsibleContainer.el.style.visibility = this.expanded ? 'inherit' : 'hidden';
    this.collapsibleContainer.el.style.height = this.expanded ? `${this.snippetAndSourceContainer.el.clientHeight}px` : '0px';
    this.updateIFrameExpanded();
  }

  private sendExpandAnalytics() {
    return this.options.bindings.usageAnalytics.logCustomEvent<IAnalyticsSmartSnippetSuggestionMeta>(
      analyticsActionCauseList.expandSmartSnippetSuggestion,
      this.analyticsSuggestionMeta,
      this.checkbox.el
    );
  }

  private sendCollapseAnalytics() {
    return this.options.bindings.usageAnalytics.logCustomEvent<IAnalyticsSmartSnippetSuggestionMeta>(
      analyticsActionCauseList.collapseSmartSnippetSuggestion,
      this.analyticsSuggestionMeta,
      this.checkbox.el
    );
  }

  private sendOpenSourceAnalytics(element: HTMLElement, href: string) {
    return this.options.bindings.usageAnalytics.logClickEvent<IAnalyticsSmartSnippetSuggestionOpenSourceMeta>(
      analyticsActionCauseList.openSmartSnippetSuggestionSource,
      {
        ...this.analyticsSuggestionMeta,
        documentTitle: this.options.source.title,
        author: Utils.getFieldValue(this.options.source, 'author'),
        documentURL: href
      },
      this.options.source,
      element
    );
  }

  private sendOpenSnippetLinkAnalytics(link: HTMLAnchorElement) {
    return this.options.bindings.usageAnalytics.logClickEvent<IAnalyticsSmartSnippetSuggestionOpenSnippetInlineLinkMeta>(
      analyticsActionCauseList.openSmartSnippetSuggestionInlineLink,
      {
        ...this.analyticsSuggestionMeta,
        linkText: link.innerText,
        linkURL: link.href
      },
      this.options.source,
      link
    );
  }
}