import { css, html, LitElement } from "lit";
import { repeat } from "lit/directives/repeat.js";
import { customElement, property } from "lit/decorators.js";
import { State, TimelineMessage } from "../types";
import "./sketch-timeline-message";

@customElement("sketch-timeline")
export class SketchTimeline extends LitElement {
  @property()
  messages: TimelineMessage[] = [];

  // See https://lit.dev/docs/components/styles/ for how lit-element handles CSS.
  // Note that these styles only apply to the scope of this web component's
  // shadow DOM node, so they won't leak out or collide with CSS declared in
  // other components or the containing web page (...unless you want it to do that).
  static styles = css`
    /* Hide views initially to prevent flash of content */
    .timeline-container .timeline,
    .timeline-container .diff-view,
    .timeline-container .chart-view,
    .timeline-container .terminal-view {
      visibility: hidden;
    }

    /* Will be set by JavaScript once we know which view to display */
    .timeline-container.view-initialized .timeline,
    .timeline-container.view-initialized .diff-view,
    .timeline-container.view-initialized .chart-view,
    .timeline-container.view-initialized .terminal-view {
      visibility: visible;
    }

    .timeline-container {
      width: 100%;
      position: relative;
    }

    /* Timeline styles that should remain unchanged */
    .timeline {
      position: relative;
      margin: 10px 0;
      scroll-behavior: smooth;
    }

    .timeline::before {
      content: "";
      position: absolute;
      top: 0;
      bottom: 0;
      left: 15px;
      width: 2px;
      background: #e0e0e0;
      border-radius: 1px;
    }

    /* Hide the timeline vertical line when there are no messages */
    .timeline.empty::before {
      display: none;
    }
  `;

  constructor() {
    super();

    // Binding methods
    this._handleShowCommitDiff = this._handleShowCommitDiff.bind(this);
  }

  /**
   * Handle showCommitDiff event
   */
  private _handleShowCommitDiff(event: CustomEvent) {
    const { commitHash } = event.detail;
    if (commitHash) {
      // Bubble up the event to the app shell
      const newEvent = new CustomEvent("show-commit-diff", {
        detail: { commitHash },
        bubbles: true,
        composed: true,
      });
      this.dispatchEvent(newEvent);
    }
  }

  // See https://lit.dev/docs/components/lifecycle/
  connectedCallback() {
    super.connectedCallback();

    // Listen for showCommitDiff events from the renderer
    document.addEventListener(
      "showCommitDiff",
      this._handleShowCommitDiff as EventListener,
    );
  }

  // See https://lit.dev/docs/components/lifecycle/
  disconnectedCallback() {
    super.disconnectedCallback();

    // Remove event listeners
    document.removeEventListener(
      "showCommitDiff",
      this._handleShowCommitDiff as EventListener,
    );
  }

  messageKey(message: TimelineMessage): string {
    // If the message has tool calls, and any of the tool_calls get a response, we need to
    // re-render that message.
    const toolCallResponses = message.tool_calls
      ?.filter((tc) => tc.result_message)
      .map((tc) => tc.tool_call_id)
      .join("-");
    return `message-${message.idx}-${toolCallResponses}`;
  }

  render() {
    return html`
      <div class="timeline-container">
        ${repeat(this.messages, this.messageKey, (message, index) => {
          let previousMessage: TimelineMessage;
          if (index > 0) {
            previousMessage = this.messages[index - 1];
          }
          return html`<sketch-timeline-message
            .message=${message}
            .previousMessage=${previousMessage}
          ></sketch-timeline-message>`;
        })}
      </div>
    `;
  }
}

declare global {
  interface HTMLElementTagNameMap {
    "sketch-timeline": SketchTimeline;
  }
}