import {LitElement, html, css} from 'lit';
import {customElement, property} from 'lit/decorators.js';

import {
  getDefaultRules,
  isInjectRule,
  Operator,
  Rule,
  getActiveTab,
} from './utils';
import {StorageUtil} from './storage';

const EMPTY_RULE = {
  disabled: false,
  target: '',
  operator: Operator.BLOCK,
  destination: '',
};

const iconStyles = css`
  .icon {
    font-family: 'Material Symbols Outlined';
    font-weight: normal;
    font-style: normal;
    font-size: 20px;
    line-height: 1;
    letter-spacing: normal;
    text-transform: none;
    display: inline-block;
    white-space: nowrap;
    word-wrap: normal;
    direction: ltr;
    -webkit-font-feature-settings: 'liga';
    -webkit-font-smoothing: antialiased;
  }
`;

/**
 * GdhApp component.
 */
@customElement('gdh-app')
export class GdhApp extends LitElement {
  @property({type: Array, attribute: false}) rules: Rule[] = [];
  @property() changeId: string = '';
  @property() announcementText = 'To get latest rules, click `reset`.';
  @property({type: Boolean}) isImport = false;
  @property() rulesStr = '';
  @property() importError = '';

  private readonly storage = new StorageUtil();

  constructor() {
    super();
    this.loadRules();
    const lastAnnouncement = window.localStorage.getItem('helper-announcement');
    if (!lastAnnouncement || lastAnnouncement !== this.announcementText) {
      window.localStorage.setItem('helper-announcement', this.announcementText);
      setTimeout(() => {
        this.announcementText = '';
      }, 3 * 1000);
    } else {
      // only show it once, if showed, don't show them again
      this.announcementText = '';
    }
  }

  private async loadRules() {
    const rules: Rule[] = await this.storage.getRules();
    this.rules = [...rules];
    this.rulesStr = JSON.stringify(this.rules, null, 2);
  }

  private async saveRules() {
    await this.storage.setRules([...this.rules]);
    this.refresh();
  }

  addNewRule() {
    this.rules = [...this.rules, {...EMPTY_RULE}];
  }

  resetRules() {
    const rules = getDefaultRules();
    this.rules = [...rules];
    this.rulesStr = JSON.stringify(this.rules, null, 2);
    window.localStorage.removeItem('helper-announcement');
    this.requestUpdate();
  }

  onRuleDeletion(event: CustomEvent<Rule>) {
    this.rules = this.rules.filter(r => r !== event.detail);
    this.rulesStr = JSON.stringify(this.rules, null, 2);
  }

  enableMeOnly(event: CustomEvent<Rule>) {
    this.rules = this.rules.map(rule => {
      const toggledRule = event.detail;
      rule.disabled = rule !== toggledRule;
      return {...rule};
    });
  }

  onRuleChanged() {
    this.requestUpdate();
  }

  async disableHelper() {
    const activeTab = await getActiveTab();
    await this.storage.setTabDisabled(activeTab.id);
    await this.refresh(activeTab);
    window.close();
  }

  private async refresh(tab?: chrome.tabs.Tab) {
    tab = tab ?? (await getActiveTab());
    if (tab) chrome.tabs.update(tab.id, {url: tab.url});
  }

  startImport() {
    this.isImport = true;
  }

  async confirmImport() {
    try {
      const rules = JSON.parse(this.rulesStr);
      this.rules = [...rules];
      await this.saveRules();
      this.isImport = false;
    } catch (e) {
      this.importError = e.message;
    }
  }

  cancelImport() {
    this.isImport = false;
  }

  handleRulesInputChange(e: Event) {
    this.rulesStr = (e.target as HTMLInputElement).value;
  }

  exportRules() {
    const dataStr =
      'data:text/json;charset=utf-8,' +
      encodeURIComponent(JSON.stringify(this.rules));
    const downloadAnchorNode = document.createElement('a');
    downloadAnchorNode.setAttribute('href', dataStr);
    downloadAnchorNode.setAttribute('download', 'rules.json');
    downloadAnchorNode.click();
    downloadAnchorNode.remove();
  }

  render() {
    return html`
      <p ?hidden=${!this.announcementText}>${this.announcementText}</p>
      <header>
        <button class="primary" @click=${this.disableHelper}>Disable</button>
      </header>
      <div ?hidden=${this.isImport}>
        <gdh-rule-set
          @enable-me-only=${this.enableMeOnly}
          @rule-deleted=${this.onRuleDeletion}
          @rule-changed=${this.onRuleChanged}
          .rules=${this.rules}
        >
        </gdh-rule-set>
        <div class="buttons">
          <button class="primary" @click=${this.saveRules}>Save</button>
          <button @click=${this.addNewRule}>Add</button>
          <button @click=${this.resetRules}>Reset</button>
          <button @click=${this.startImport}>Import</button>
          <button @click=${this.exportRules}>Export</button>
        </div>
      </div>
      <div ?hidden=${!this.isImport}>
        <p ?hidden=${!this.importError}>${this.importError}</p>
        <textarea
          name="rules"
          .value=${this.rulesStr}
          @input=${this.handleRulesInputChange}
        >
        </textarea>
        <div class="buttons">
          <button @click=${this.confirmImport}>Import</button>
          <button @click=${this.cancelImport}>Cancel</button>
          <button @click=${this.resetRules}>Reset</button>
        </div>
      </div>
    `;
  }

  static get styles() {
    return css`
      :host {
        display: block;
        padding: 10px;
      }
      p {
        background: yellow;
        padding: 10px;
      }
      button {
        color: #1565c0;
        background: transparent;
        font-family: Roboto, sans-serif;
        font-size: 14px;
        font-weight: 400;
        text-transform: uppercase;
        user-select: none;
        box-sizing: content-box;
        border-radius: 4px;
        border: none;
        padding: 4px 8px;
        cursor: pointer;
        outline: none;
      }
      button:hover {
        background-color: #f4f0fa;
      }
      button.primary {
        color: white;
        background-color: #1565c0;
      }
      button.primary:hover {
        background-color: #2575d0;
      }
      header {
        display: flex;
        flex-direction: row-reverse;
      }
      textarea {
        min-width: 500px;
        min-height: 500px;
      }
    `;
  }
}

/**
 * GdhRuleSet component.
 */
@customElement('gdh-rule-set')
export class GdhRuleSet extends LitElement {
  @property({type: Array, attribute: false}) rules: Rule[] = [];

  render() {
    return html`
      <ul>
        <li class="header">
          <span></span>
          <span>Target</span>
          <span>Operator</span>
          <span>Destination</span>
          <span></span>
        </li>
        ${this.rules.map(
          rule => html`<li><gdh-rule-item .rule=${rule}></gdh-rule-item></li>`
        )}
      </ul>
    `;
  }

  static get styles() {
    return css`
      :host {
        display: block;
        position: relative;
        padding: 16px 0;
      }
      ul {
        list-style: none;
        margin: 0;
        padding: 0;
      }
      ul li {
        margin: 5px 0;
      }
      ul li.header {
        display: flex;
      }
      li.header span {
        text-align: center;
        font-weight: bold;
      }
      li.header span:nth-child(1) {
        flex-basis: 20px;
      }
      li.header span:nth-child(2) {
        flex: 1;
        flex-basis: 220px;
      }
      li.header span:nth-child(3) {
        flex-basis: 140px;
      }
      li.header span:nth-child(4) {
        flex: 1;
        flex-basis: 220px;
      }
      li.header span:nth-child(5) {
        flex-basis: 20px;
      }
    `;
  }
}

/**
 * GdhRuleItem component.
 */
@customElement('gdh-rule-item')
export class GdhRuleItem extends LitElement {
  @property({type: Object, attribute: false}) rule: Rule = {...EMPTY_RULE};

  operators = [
    Operator.BLOCK,
    Operator.REDIRECT,
    Operator.INJECT_CSS,
    Operator.INJECT_HTML_CODE,
    Operator.INJECT_EXP,
    Operator.ADD_REQUEST_HEADER,
    Operator.ADD_RESPONSE_HEADER,
    Operator.REMOVE_RESPONSE_HEADER,
  ];

  handleInputOnTarget(e: Event) {
    this.rule.target = (e.target as HTMLInputElement).value;
    this.requestUpdate();
  }

  handleInputOnDestination(e: Event) {
    this.rule.destination = (e.target as HTMLInputElement).value;
    this.requestUpdate();
  }

  onSelectedChange(e: CustomEvent<number>) {
    this.rule.operator = this.operators[e.detail];
    this.requestUpdate();
  }

  onRuleDeletion(rule: Rule) {
    this.dispatchEvent(
      new CustomEvent<Rule>('rule-deleted', {
        detail: rule,
        bubbles: true,
        composed: true,
      })
    );
  }

  toggleDisable(e: KeyboardEvent) {
    this.rule.disabled = !this.rule.disabled;
    // notify the change
    this.dispatchEvent(
      new CustomEvent<Rule>('rule-changed', {
        detail: this.rule,
        bubbles: true,
        composed: true,
      })
    );
  }

  enableOnlyMe(e: KeyboardEvent) {
    this.dispatchEvent(
      new CustomEvent<Rule>('enable-me-only', {
        detail: this.rule,
        bubbles: true,
        composed: true,
      })
    );
  }

  render() {
    return html`
      <div class="checkboxContainer">
        <input
          type="checkbox"
          .checked=${!this.rule.disabled}
          @dblclick=${this.enableOnlyMe}
          @click=${this.toggleDisable}
        />
      </div>
      <input
        class="target"
        .disabled=${isInjectRule(this.rule)}
        type="text"
        .value=${this.rule.target}
        @input=${this.handleInputOnTarget}
      />
      <gdh-dropdown
        .selectedIndex=${this.operators.indexOf(this.rule.operator)}
        @select-changed=${this.onSelectedChange}
        .items=${this.operators}
      >
      </gdh-dropdown>
      <textarea
        name="destination"
        .value=${this.rule.destination}
        @input=${this.handleInputOnDestination}
        .disabled=${this.rule.operator === Operator.BLOCK}
      >
      </textarea>
      <div class="deleteContainer">
        <span
          class="icon deleteButton"
          @click=${this.onRuleDeletion.bind(this, this.rule)}
        >
          delete
        </span>
      </div>
    `;
  }

  static get styles() {
    return [
      iconStyles,
      css`
        :host {
          position: relative;
          display: flex;
          flex-direction: row;
        }
        .deleteContainer {
          flex-basis: 20px;
          display: flex;
          flex-direction: column;
          justify-content: center;
          margin-left: 8px;
        }
        .deleteButton {
          cursor: pointer;
        }
        .deleteButton:hover {
          background: #eee;
        }
        .checkboxContainer {
          flex-basis: 16px;
          display: flex;
          flex-direction: column;
          justify-content: center;
          margin-right: 8px;
        }
        input[type='checkbox'] {
          width: 16px;
          height: 16px;
        }
        input[type='text'] {
          font-family: Roboto, sans-serif;
          font-size: 13px;
        }
        textarea {
          font-family: 'Roboto Mono', monospace;
          font-size: 12px;
        }
        input[type='text'],
        textarea {
          flex: 1;
          min-width: 220px;
          outline: none;
          border: none;
          border-bottom: 1px solid #ccc;
        }
        input[type='text']:focus,
        textarea:focus {
          border-bottom: 1px solid #3c88fd;
          background: #e8f0fe;
        }
        input[disabled],
        textarea[disabled] {
          background: #e8eaed;
        }
      `,
    ];
  }
}

/**
 * GdhDropdown component.
 */
@customElement('gdh-dropdown')
export class GdhDropdown extends LitElement {
  @property({type: Array, attribute: false}) items: unknown[] = [];
  @property({type: Number}) selectedIndex: number = 0;
  @property({type: Boolean}) isVisible = false;

  handleSelect(idx: number) {
    this.selectedIndex = idx;
    this.dispatchEvent(
      new CustomEvent<number>('select-changed', {
        detail: idx,
        bubbles: true,
        composed: true,
      })
    );
    this.isVisible = false;
  }

  toggleVisible(e: Event) {
    this.isVisible = (e.target as HTMLInputElement).checked;
  }

  render() {
    return html`
      <label for="trigger" @click=${this.toggleVisible}>
        <div class="selected-value">${this.items[this.selectedIndex]}</div>
        <input
          .checked=${this.isVisible}
          @input=${this.toggleVisible}
          type="checkbox"
          name="trigger"
        />
        <ul class="options">
          ${this.items.map(
            (item, i) => html`
              <li
                @click=${this.handleSelect.bind(this, i)}
                class="${i === this.selectedIndex ? 'active' : ''}"
              >
                ${item}
              </li>
            `
          )}
        </ul>
        <span class="icon">expand_more</span>
      </label>
    `;
  }

  static get styles() {
    return [
      iconStyles,
      css`
        :host {
          position: relative;
          display: flex;
          flex-direction: column;
        }
        label {
          background-color: #f1f1f1;
          margin: 0 5px;
          line-height: 16px;
        }
        span.icon {
          position: absolute;
          top: 6px;
          right: 6px;
          pointer-events: none;
        }
        .selected-value {
          padding: 8px 16px 8px 8px;
          min-width: 100px;
        }
        ul {
          display: none;
          list-style: none;
          margin: 0;
          padding: 0;
          width: 100%;
          position: absolute;
          top: 100%;
          left: 0;
          background: #eee;
          z-index: 1;
        }
        input {
          opacity: 0;
          position: absolute;
          top: 0;
          width: 100%;
          height: 100%;
          cursor: pointer;
        }
        input:checked + ul {
          display: block;
          box-shadow: 0 2px 1px -1px rgba(0, 0, 0, 0.2),
            0 1px 1px 0 rgba(0, 0, 0, 0.14), 0 1px 3px 0 rgba(0, 0, 0, 0.12);
        }
        input:checked + ul li:hover {
          background: #ddd;
        }
        input:checked + ul li {
          padding: 5px 10px;
          cursor: pointer;
        }
        input:checked + ul li.active,
        input:checked + ul li.active:hover {
          background-color: #fff;
        }
        input:checked + ul + i {
          transform: rotate(-135deg);
          -webkit-transform: rotate(-135deg);
        }
      `,
    ];
  }
}