import fs from "node:fs";
import path from "node:path";
import { test, type Page, type TestInfo } from "@playwright/test";
import * as narration from "./narration";
import { renderFinalVideo } from "./video-render";
import type { Clip } from "./subtitles";

const DEMO = !!process.env.PW_DEMO;

/**
 * Wraps test.step() so every step of a demo spec produces a captioned
 * screenshot, and — in PW_DEMO mode — a native Playwright screencast
 * recording with cursor annotations, chapter-title cards, burned-in
 * subtitles and (when `say` is available) spoken Spanish narration.
 * Screenshots/video/subtitles land in e2e-docs/<slug>/ and are also
 * attached to the Playwright HTML report; save() stitches everything into
 * a Markdown walkthrough that can be published as-is.
 */
export class FeatureDoc {
  private steps: { title: string; caption: string; file: string }[] = [];
  private clips: Clip[] = [];
  private readonly dir: string;
  private recordingStartedAt = 0;

  constructor(
    private page: Page,
    private testInfo: TestInfo,
    private slug: string,
    private title: string,
    private intro: string,
  ) {
    this.dir = path.resolve("e2e-docs", slug);
    fs.rmSync(this.dir, { recursive: true, force: true });
    fs.mkdirSync(this.dir, { recursive: true });
  }

  /** Starts the native screencast recording. Call before the first step(). */
  async start() {
    if (!DEMO) return;
    this.recordingStartedAt = Date.now();
    await this.page.screencast.start({
      path: path.join(this.dir, "raw.webm"),
      size: { width: 1920, height: 1080 },
    });
    await this.page.screencast.showActions({ cursor: "pointer" });
  }

  async step(title: string, caption: string, fn: () => Promise<void>) {
    const narrationPromise = DEMO
      ? narration.synthesize(caption, this.testInfo.outputDir, this.clips.length)
      : Promise.resolve(null);

    const stepStart = Date.now();
    if (DEMO) {
      await this.page.screencast.showChapter(title, { description: caption, duration: 1500 });
    }

    await test.step(title, fn);

    const narrationResult = await narrationPromise;
    if (DEMO) {
      const elapsed = Date.now() - stepStart;
      const target = (narrationResult?.durationMs ?? 0) + 300;
      if (target > elapsed) await this.page.waitForTimeout(target - elapsed);
    }

    const file = `${String(this.steps.length + 1).padStart(2, "0")}-${title
      .toLowerCase()
      .normalize("NFD")
      .replace(/[̀-ͯ]+/g, "")
      .replace(/[^a-z0-9]+/g, "-")
      .replace(/^-|-$/g, "")}.png`;
    const body = await this.page.screenshot({
      path: path.join(this.dir, file),
      animations: "disabled",
    });
    await this.testInfo.attach(title, { body, contentType: "image/png" });
    this.steps.push({ title, caption, file });

    if (DEMO) {
      this.clips.push({
        title,
        caption,
        file,
        startMs: stepStart - this.recordingStartedAt,
        endMs: Date.now() - this.recordingStartedAt,
        narration: narrationResult,
      });
    }
  }

  async save() {
    let videoName = "video.mp4";
    if (DEMO) {
      await this.page.screencast.stop();
      const { videoFile, degraded } = await renderFinalVideo({
        rawWebmPath: path.join(this.dir, "raw.webm"),
        clips: this.clips,
        outDir: this.dir,
      });
      for (const warning of degraded) console.warn(`[${this.slug}] ${warning}`);
      videoName = path.basename(videoFile);
      await this.testInfo.attach("video", {
        path: videoFile,
        contentType: videoName.endsWith(".mp4") ? "video/mp4" : "video/webm",
      });
    }

    const md = [
      `# ${this.title}`,
      "",
      this.intro,
      "",
      `> Generado automáticamente por \`${path.basename(this.testInfo.file)}\` — ${this.steps.length} pasos. El video completo del recorrido está en [${videoName}](${videoName}).`,
      "",
      ...this.steps.flatMap((s, i) => [
        `## ${i + 1}. ${s.title}`,
        "",
        s.caption,
        "",
        `![${s.title}](${s.file})`,
        "",
      ]),
    ].join("\n");
    fs.writeFileSync(path.join(this.dir, "index.md"), md);
  }
}