// utils/normalizeQuestionMedia.ts
// Shared helper for normalizing media URLs in quiz questions.
// Call before saving to KV/SQL to ensure consistent data format.

import { hashText } from "../services/stateMiddleware.ts";

/**
 * Question structure with media fields
 */
export interface QuizQuestion {
  id: string;
  text_1: string;
  text_2: string;
  background_file: string;
  background_image_data: string;
  audio_file_1: string;
  audio_file_2: string;
}

/**
 * Normalizes media URLs in a question to the expected local format.
 * Call this BEFORE saving to KV/SQL to ensure consistent data.
 *
 * Expected output formats:
 * - background_image_data: "/api/ai-images/file/{filename}" or "/api/image-blob/{hashName}" or base64
 *   (legacy http URLs are left unchanged - they'll be handled by the serving layer)
 * - audio_file_1/2: "{hashName}" or "{hashName}.webm" (just the hash, not a URL)
 *
 * Note: background_file stores the user's description (not a filename).
 * The actual filename is embedded in the background_image_data URL path.
 *
 * @param question - The question object to normalize (mutated in place)
 * @returns true if any field was modified
 */
export async function normalizeQuestionMedia(
  question: QuizQuestion | null | undefined,
): Promise<boolean> {
  let changed = false;

  if (!question) {
    return false;
  }

  // Note: We no longer try to derive background_image_data from background_file
  // because background_file now stores the user's description, not a filename.
  // Legacy http URLs in background_image_data are left as-is.
  // New images should already have correct /api/... URLs when saved.

  // Normalize audio_file_1
  if (question.text_1 && question.audio_file_1) {
    if (question.audio_file_1.startsWith("http")) {
      // Convert to hash-based local reference
      const hash = await hashText(question.id + ":" + question.text_1);
      question.audio_file_1 = hash + "";
      changed = true;
    }
  }

  // Normalize audio_file_2
  if (question.text_2 && question.audio_file_2) {
    if (question.audio_file_2.startsWith("http")) {
      const hash = await hashText(question.id + ":" + question.text_2);
      question.audio_file_2 = hash + "";
      changed = true;
    }
  }

  return changed;
}

/**
 * Normalizes all questions in a quiz config.
 * @param questions - Array of questions to normalize (mutated in place)
 * @returns true if any question was modified
 */
export async function normalizeQuizMedia(
  questions: Array<QuizQuestion | null | undefined>,
): Promise<boolean> {
  let anyChanged = false;

  for (const question of questions) {
    if (!question) continue;
    const changed = await normalizeQuestionMedia(question);
    anyChanged = anyChanged || changed;
  }

  return anyChanged;
}