import { css, html, LitElement } from "lit";
import { classMap } from "lit/directives/class-map.js";
import { createRef, ref } from "lit/directives/ref.js";
import { customElement, property, state } from "lit/decorators.js";

import "./entrypoints/custom-icon.ts";

export type TabItem = {
  icon: string;
  label: string;
  value: string;
};

export class SelectTabEvent extends Event {
  value: string;

  constructor(value: string) {
    super("select-tab");
    this.value = value;
  }
}

@customElement("lens-controls-shell")
export class LensControlsShell extends LitElement {
  @property({ attribute: true, type: Array })
  tabs: TabItem[] = [];

  @property({ attribute: "active-tab" })
  activeTab?: string;

  @state()
  private _isOpen = false;

  private _controlPanelRef = createRef<HTMLDivElement>();

  static override styles = css`
    :host {
      --shadow: 0 0.5rem 0.5rem #3333;
      --background: #fff;
      --border-color: #ccc;
      --border-radius: 0.5rem;
    }

    #container-positioner {
      position: fixed;
      bottom: 2rem;
      display: flex;
      justify-content: center;
      align-items: flex-end;
      overflow: visible;
      width: 100%;
      height: 0;
    }

    #container {
      display: grid;
      grid-template-columns: max-content max-content 1rem max-content;
      filter: drop-shadow(var(--shadow));
    }

    #tab-box {
      height: 2rem;
      display: flex;
      align-items: center;
      list-style-type: none;
      padding: 0.5rem;
      margin: 0;
      border: solid 1px var(--border-color);
      border-right: none;
      border-top-left-radius: var(--border-radius);
      border-bottom-left-radius: var(--border-radius);
      background: var(--background);
      grid-row: 2;

      & button {
        appearance: none;
        background: none;
        border: none;
        font-size: inherit;
        padding: 0.25rem 0.5rem;
        border-radius: 0.25rem;
        font-family: inherit;
        cursor: pointer;
        height: 2rem;
      }

      & button.active {
        background: #39f3;
      }
    }

    #control-bar {
      height: 3rem;
      flex-shrink: 0;
      border: solid 1px var(--border-color);
      border-top-right-radius: var(--border-radius);
      border-bottom-right-radius: var(--border-radius);
      overflow: hidden;
      width: 40rem;
      grid-row: 2;
      background: var(--background);

      &.open {
        border-top-right-radius: 0;
      }
    }

    #control-buttons {
      height: 3rem;
      grid-row: 2;
      grid-column: 4;
      height: 100%;
    }

    #control-panel-positioner {
      grid-template-columns: subgrid;
      grid-column: 2;
      grid-row: 1;
      position: relative;
      overflow: visible;
      /* Flexbox positioning is required for Safari */
      display: flex;
      align-items: flex-end;
      anchor-name: --control-bar;
    }

    #control-panel-container:popover-open {
      inset: unset;
      border: solid 1px var(--border-color);
      border-bottom: none;
      border-top-left-radius: var(--border-radius);
      border-top-right-radius: var(--border-radius);
      margin: 0;
      position: fixed;
      display: block;
      width: 40rem;
      /* Anchor positioning is required for Chromium */
      position-anchor: --control-bar;
      position-area: top;
      padding: 0;
      background: var(--background);
      box-shadow: var(--shadow);
      /* Clip drop shadow */
      clip-path: polygon(
        -100% -100%,
        200% -100%,
        200% 200%,
        100% 200%,
        100% 100%,
        -100% 100%
      );
    }

    #control-panel {
      padding: 0.5rem;
      overflow: auto;
      max-height: 8rem;
    }
  `;

  open(): void {
    this._controlPanelRef.value?.showPopover();
  }

  protected override render() {
    return html`
      <div id="container-positioner">
        <div id="container">
          <ul id="tab-box" @click="${this.open}">
            ${this.tabs.map(({ icon, label, value }) =>
        html`
          <li>
            <button type="button" class="${classMap({
            active: this.activeTab === value,
          })}" @click="${() => {
            this.dispatchEvent(new SelectTabEvent(value));
          }}">
              ${icon
            ? html`<custom-icon name=${icon} alt=${label}></custom-label>`
            : label}
            </button>
          </li>
        `
      )}
          </ul>
          <div id="control-bar" class="${classMap({
        open: this._isOpen,
      })}" @click="${this.open}">
            <slot name="control-bar"></slot>
          </div>
          <div id="control-buttons">
            <slot name="control-buttons"></slot>
          </div>
          <div id="control-panel-positioner">
            <div
              id="control-panel-container"
              popover="auto"
              ${ref(
        this._controlPanelRef,
      )}
              @toggle="${(ev: ToggleEvent) => {
        this._isOpen = ev.newState === "open";
      }}"
            >
              <div id="control-panel">
                <slot name="control-panel"></slot>
              </div>
            </div>
          </div>
        </div>
      </div>
    `;
  }
}