<script lang="ts">
  import { segments, speakers } from '$lib/stores/transcript';
  import { currentTimeMs, isPlaying } from '$lib/stores/playback';
  import type { Segment, Word, Speaker } from '$lib/types/transcript';

  interface Props {
    onWordClick?: (timeMs: number) => void;
    onTextEdit?: (segmentId: string, newText: string) => void;
  }

  let { onWordClick, onTextEdit }: Props = $props();

  let transcriptContainer: HTMLDivElement;
  let autoScroll = $state(true);
  let lastActiveSegmentId = $state('');
  let userScrollTimeout: ReturnType<typeof setTimeout> | null = null;

  function getSpeakerName(speakerId: string | null, speakerList: Speaker[]): string {
    if (!speakerId) return 'Unknown';
    const speaker = speakerList.find(s => s.id === speakerId);
    return speaker?.display_name || speaker?.label || 'Unknown';
  }

  function getSpeakerColor(speakerId: string | null, speakerList: Speaker[]): string {
    if (!speakerId) return '#888';
    const speaker = speakerList.find(s => s.id === speakerId);
    return speaker?.color || '#888';
  }

  function formatTimestamp(ms: number): string {
    const totalSeconds = Math.floor(ms / 1000);
    const m = Math.floor(totalSeconds / 60);
    const s = totalSeconds % 60;
    return `${m}:${s.toString().padStart(2, '0')}`;
  }

  function isWordActive(word: Word, currentMs: number): boolean {
    return currentMs >= word.start_ms && currentMs <= word.end_ms;
  }

  function isSegmentActive(segment: Segment, currentMs: number): boolean {
    return currentMs >= segment.start_ms && currentMs <= segment.end_ms;
  }

  let editingSegmentId = $state<string | null>(null);
  let editText = $state('');

  function handleWordClick(word: Word) {
    onWordClick?.(word.start_ms);
  }

  function startEditing(segment: Segment) {
    editingSegmentId = segment.id;
    // Combine word texts or fall back to segment text
    editText = segment.words.length > 0
      ? segment.words.map(w => w.word).join(' ')
      : segment.text;
  }

  function finishEditing(segmentId: string) {
    const trimmed = editText.trim();
    if (trimmed) {
      // Update the segment text in the store
      segments.update(segs => segs.map(s => {
        if (s.id !== segmentId) return s;
        return {
          ...s,
          text: trimmed,
          original_text: s.original_text ?? s.text,
          is_edited: true,
          edited_at: new Date().toISOString(),
        };
      }));
      onTextEdit?.(segmentId, trimmed);
    }
    editingSegmentId = null;
  }

  function handleEditKeydown(e: KeyboardEvent, segmentId: string) {
    if (e.key === 'Escape') {
      editingSegmentId = null;
    } else if (e.key === 'Enter' && !e.shiftKey) {
      e.preventDefault();
      finishEditing(segmentId);
    }
  }

  // Pause auto-scroll when user manually scrolls, resume after 3 seconds
  function handleScroll() {
    if (!$isPlaying) return;
    autoScroll = false;
    if (userScrollTimeout) clearTimeout(userScrollTimeout);
    userScrollTimeout = setTimeout(() => {
      autoScroll = true;
    }, 3000);
  }

  // Auto-scroll to the active segment during playback
  $effect(() => {
    if (!$isPlaying || !autoScroll || !transcriptContainer) return;
    const currentMs = $currentTimeMs;
    const activeSegment = $segments.find(s => isSegmentActive(s, currentMs));
    if (!activeSegment || activeSegment.id === lastActiveSegmentId) return;
    lastActiveSegmentId = activeSegment.id;

    const el = transcriptContainer.querySelector(`[data-segment-id="${activeSegment.id}"]`);
    if (el) {
      el.scrollIntoView({ behavior: 'smooth', block: 'center' });
    }
  });
</script>

<div class="transcript-editor" bind:this={transcriptContainer} onscroll={handleScroll}>
  {#if $segments.length === 0}
    <div class="empty-state">
      <p>No transcript yet</p>
      <p class="hint">Import an audio file and run transcription to get started</p>
    </div>
  {:else}
    {#each $segments as segment (segment.id)}
      <div
        class="segment"
        class:active={isSegmentActive(segment, $currentTimeMs)}
        data-segment-id={segment.id}
      >
        <div class="segment-header">
          <span
            class="speaker-label"
            style="border-left-color: {getSpeakerColor(segment.speaker_id, $speakers)}"
          >
            {getSpeakerName(segment.speaker_id, $speakers)}
          </span>
          <span class="timestamp">{formatTimestamp(segment.start_ms)}</span>
        </div>
        {#if editingSegmentId === segment.id}
          <div class="segment-edit">
            <textarea
              class="edit-textarea"
              bind:value={editText}
              onblur={() => finishEditing(segment.id)}
              onkeydown={(e) => handleEditKeydown(e, segment.id)}
            ></textarea>
            <span class="edit-hint">Enter to save, Esc to cancel</span>
          </div>
        {:else}
          <!-- svelte-ignore a11y_no_static_element_interactions -->
          <div class="segment-text" ondblclick={() => startEditing(segment)}>
            {#each segment.words as word (word.id)}
              <span
                class="word"
                class:word-active={isWordActive(word, $currentTimeMs)}
                onclick={() => handleWordClick(word)}
                role="button"
                tabindex="0"
                onkeydown={(e) => { if (e.key === 'Enter') handleWordClick(word); }}
              >{word.word} </span>
            {:else}
              <span class="segment-plain-text">{segment.text}</span>
            {/each}
            {#if segment.is_edited}
              <span class="edited-badge">edited</span>
            {/if}
          </div>
        {/if}
      </div>
    {/each}
  {/if}
</div>

<style>
  .transcript-editor {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
    background: #16213e;
    border-radius: 8px;
    color: #e0e0e0;
  }
  .empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: #666;
  }
  .hint {
    font-size: 0.875rem;
    color: #555;
  }
  .segment {
    margin-bottom: 1rem;
    padding: 0.5rem;
    border-radius: 4px;
    transition: background-color 0.2s;
  }
  .segment.active {
    background: rgba(233, 69, 96, 0.1);
  }
  .segment-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.25rem;
  }
  .speaker-label {
    font-weight: 600;
    font-size: 0.875rem;
    border-left: 3px solid;
    padding-left: 0.5rem;
  }
  .timestamp {
    color: #666;
    font-size: 0.75rem;
    font-variant-numeric: tabular-nums;
  }
  .segment-text {
    line-height: 1.6;
    padding-left: 0.75rem;
  }
  .word {
    cursor: pointer;
    border-radius: 2px;
    padding: 0 1px;
    transition: background-color 0.15s;
  }
  .word:hover {
    background: rgba(233, 69, 96, 0.2);
  }
  .word-active {
    background: rgba(233, 69, 96, 0.35);
    color: #fff;
  }
  .segment-plain-text {
    color: #ccc;
  }
  .segment-edit {
    padding-left: 0.75rem;
  }
  .edit-textarea {
    width: 100%;
    min-height: 3rem;
    background: #1a1a2e;
    color: #e0e0e0;
    border: 1px solid #e94560;
    border-radius: 4px;
    padding: 0.5rem;
    font-family: inherit;
    font-size: inherit;
    line-height: 1.6;
    resize: vertical;
  }
  .edit-textarea:focus {
    outline: none;
    border-color: #ff6b81;
  }
  .edit-hint {
    font-size: 0.7rem;
    color: #666;
  }
  .edited-badge {
    font-size: 0.65rem;
    color: #e94560;
    background: rgba(233, 69, 96, 0.15);
    padding: 0.1rem 0.3rem;
    border-radius: 3px;
    margin-left: 0.5rem;
    vertical-align: middle;
  }
</style>
