/**
 * Utility functions for handling transcript generation from utterances
 */

/**
 * Generate a plain text transcript from utterances array
 * @param utterances - Array of utterance objects with text property
 * @returns Plain text transcript string
 */
export function generateTranscriptFromUtterances(
  utterances?: Array<{ text: string; speakerId?: string; offset?: number; duration?: number }> | null
): string {
  if (!utterances || utterances.length === 0) {
    return '';
  }

  // Sort utterances by offset if available
  const sortedUtterances = [...utterances].sort((a, b) => {
    const offsetA = a.offset || 0;
    const offsetB = b.offset || 0;
    return offsetA - offsetB;
  });

  // Concatenate all utterance texts with spaces
  return sortedUtterances
    .map(utterance => utterance.text)
    .filter(text => text && text.trim() !== '')
    .join(' ');
}

/**
 * Check if transcript data exists (either in utterances or legacy transcript fields)
 * @param memo - The memo object to check
 * @returns Boolean indicating if transcript exists
 */
export function hasTranscript(memo: any): boolean {
  // Check utterances first (new structure)
  if (memo?.source?.utterances && memo.source.utterances.length > 0) {
    return true;
  }
  
  // Check legacy fields for backward compatibility
  return !!(
    memo?.transcript ||
    memo?.source?.transcript ||
    memo?.source?.content ||
    memo?.source?.transcription ||
    memo?.metadata?.transcript
  );
}

/**
 * Get transcript text from memo (generates from utterances or returns legacy transcript)
 * @param memo - The memo object
 * @returns The transcript text
 */
export function getTranscriptText(memo: any): string {
  // If utterances exist, generate transcript from them
  if (memo?.source?.utterances && memo.source.utterances.length > 0) {
    return generateTranscriptFromUtterances(memo.source.utterances);
  }
  
  // Fall back to legacy transcript fields
  return (
    memo?.transcript ||
    memo?.source?.transcript ||
    memo?.source?.content ||
    memo?.source?.transcription ||
    memo?.metadata?.transcript ||
    ''
  );
}

/**
 * Get utterances from various possible locations in memo
 * @param memo - The memo object
 * @returns Array of utterances or null
 */
export function getUtterances(memo: any): Array<{ text: string; speakerId?: string; offset?: number; duration?: number }> | null {
  // Check primary location
  if (memo?.source?.utterances && Array.isArray(memo.source.utterances)) {
    return memo.source.utterances;
  }
  
  // Check metadata location (for backward compatibility)
  if (memo?.metadata?.utterances && Array.isArray(memo.metadata.utterances)) {
    return memo.metadata.utterances;
  }
  
  // If only transcript exists, create a single utterance
  const transcriptText = memo?.transcript || 
    memo?.source?.transcript || 
    memo?.source?.content || 
    memo?.source?.transcription || 
    memo?.metadata?.transcript;
    
  if (transcriptText) {
    return [{
      text: transcriptText,
      speakerId: 'default',
      offset: 0,
      duration: 0
    }];
  }
  
  return null;
}

/**
 * Check if a memo is a combined memo
 * @param memo - The memo object
 * @returns Boolean indicating if it's a combined memo
 */
export function isCombinedMemo(memo: any): boolean {
  return memo?.source?.type === 'combined';
}

/**
 * Get combined memo recordings with their transcripts
 * @param memo - The memo object
 * @returns Array of recordings with transcript data or empty array
 */
export function getCombinedMemoRecordings(memo: any): Array<{
  title: string;
  transcript: string;
  utterances: Array<{ text: string; speakerId: string; offset: number; duration: number }>;
  speakers: Record<string, string>;
  timestamp: string;
  index: number;
}> {
  if (!isCombinedMemo(memo) || !memo?.source?.additional_recordings) {
    return [];
  }

  return memo.source.additional_recordings.map((recording: any, index: number) => {
    const memoMetadata = recording.memo_metadata || {};
    
    return {
      title: memoMetadata.original_title || memoMetadata.display_title || `Recording ${index + 1}`,
      transcript: recording.transcript || '',
      utterances: recording.utterances || [],
      speakers: recording.speakers || {},
      timestamp: recording.timestamp || memoMetadata.original_created_at || '',
      index: memoMetadata.combine_index ?? index,
    };
  });
}

/**
 * Calculate total audio duration for combined memos
 * @param memo - The memo object
 * @returns Total duration in seconds or 0
 */
export function getCombinedMemoDuration(memo: any): number {
  if (!isCombinedMemo(memo) || !memo?.source?.additional_recordings) {
    return 0;
  }

  let totalDuration = 0;
  
  memo.source.additional_recordings.forEach((recording: any) => {
    if (recording.duration) {
      totalDuration += recording.duration;
    }
  });

  return totalDuration;
}