// ChatPane — mirrors ui/src/components/chat/* with user/ask/result/progress bubbles
function Bubble({ role, children, footer }) {
  const isUser = role === 'user';
  const style = {
    maxWidth: '85%',
    padding: '10px 14px',
    borderRadius: 16,
    fontSize: 13,
    lineHeight: 1.55,
    whiteSpace: 'pre-wrap',
    wordBreak: 'break-word',
  };
  if (isUser) {
    Object.assign(style, { background: '#f1f5f9', color: '#0f172a', borderBottomRightRadius: 4, alignSelf: 'flex-end' });
  } else if (role === 'ask') {
    Object.assign(style, { background: '#fef9c3', color: '#854d0e', border: '1px solid #fde68a', borderBottomLeftRadius: 4 });
  } else if (role === 'result') {
    Object.assign(style, { background: '#ecfdf5', color: '#065f46', border: '1px solid #a7f3d0', borderBottomLeftRadius: 4 });
  } else {
    Object.assign(style, { background: '#fff', color: '#0f172a', border: '1px solid #e2e8f0', borderBottomLeftRadius: 4 });
  }
  return (
    <div style={{ display: 'flex', flexDirection: 'column', alignItems: isUser ? 'flex-end' : 'flex-start', gap: 4 }}>
      <div style={style}>{children}</div>
      {footer && <div style={{ fontSize: 10, color: '#94a3b8' }}>{footer}</div>}
    </div>
  );
}

function ProgressBubble({ text }) {
  return (
    <div style={{
      alignSelf: 'flex-start', background: '#f1f5f9', color: '#475569',
      padding: '8px 12px', borderRadius: 12, fontSize: 12,
      display: 'inline-flex', alignItems: 'center', gap: 8,
    }}>
      <Spinner />
      <span>{text}</span>
    </div>
  );
}

function ChatHeader({ task, onOpenDetail, detailOpen }) {
  return (
    <div style={{
      flexShrink: 0, padding: '12px 16px', borderBottom: '1px solid #e2e8f0', background: '#fff',
      display: 'flex', alignItems: 'center', justifyContent: 'space-between', gap: 12,
    }}>
      <div style={{ minWidth: 0 }}>
        <div style={{ fontSize: 10, fontFamily: 'IBM Plex Mono, monospace', color: '#94a3b8', letterSpacing: '.08em' }}>
          TASK #{task.id}
        </div>
        <div style={{ fontSize: 15, fontWeight: 700, color: '#0f172a', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>
          {task.title}
        </div>
      </div>
      <div style={{ display: 'flex', alignItems: 'center', gap: 10 }}>
        <StatusBadge status={task.status} />
        <button onClick={onOpenDetail} style={{
          padding: '6px 10px', borderRadius: 8, border: '1px solid #e2e8f0',
          background: detailOpen ? '#eff6ff' : '#fff',
          color: detailOpen ? '#1d4ed8' : '#475569',
          fontSize: 12, fontWeight: 600, cursor: 'pointer', fontFamily: 'inherit',
        }}>詳細</button>
      </div>
    </div>
  );
}

function Composer({ onSend, disabled }) {
  const [text, setText] = React.useState('');
  const [sending, setSending] = React.useState(false);
  const [error, setError] = React.useState(null);
  const send = async () => {
    if (!text.trim() || disabled || sending) return;
    setError(null); setSending(true);
    try {
      await Promise.resolve(onSend(text.trim()));
      setText('');
    } catch (e) {
      setError(e?.message || '送信に失敗しました');
    } finally {
      setSending(false);
    }
  };
  return (
    <div style={{ flexShrink: 0, borderTop: '1px solid #e2e8f0', background: '#fff', padding: 12 }}>
      {error && (
        <div style={{
          marginBottom: 8, padding: '8px 10px', background: '#fef2f2', border: '1px solid #fecaca',
          color: '#b91c1c', borderRadius: 8, fontSize: 12, display: 'flex', alignItems: 'center', justifyContent: 'space-between', gap: 8,
        }}>
          <span>⚠ {error}</span>
          <button onClick={send} style={{
            padding: '2px 8px', borderRadius: 6, border: '1px solid #fecaca',
            background: '#fff', color: '#b91c1c', fontSize: 11, fontWeight: 700,
            cursor: 'pointer', fontFamily: 'inherit',
          }}>再送信</button>
        </div>
      )}
      <div style={{
        display: 'flex', alignItems: 'flex-end', gap: 8, background: '#f8fafc',
        border: '1px solid #e2e8f0', borderRadius: 12, padding: 8,
        opacity: disabled ? 0.6 : 1,
      }}>
        <button style={{ padding: 6, background: 'transparent', border: 'none', color: '#94a3b8', cursor: 'pointer' }}>
          <IconAttach width={16} height={16} />
        </button>
        <textarea
          value={text}
          disabled={disabled || sending}
          onChange={(e) => setText(e.target.value)}
          onKeyDown={(e) => { if (e.key === 'Enter' && (e.metaKey || e.ctrlKey)) { e.preventDefault(); send(); } }}
          rows={2}
          placeholder={disabled ? '送信できません' : 'メッセージを入力 (⌘+Enter で送信)'}
          style={{
            flex: 1, resize: 'none', border: 'none', outline: 'none', background: 'transparent',
            fontFamily: 'inherit', fontSize: 13, color: '#0f172a', lineHeight: 1.5, minHeight: 32,
          }}
        />
        <button onClick={send} disabled={disabled || sending || !text.trim()} style={{
          padding: '6px 14px', background: '#2563eb', color: '#fff', borderRadius: 8,
          fontSize: 12, fontWeight: 700, border: 'none',
          cursor: (disabled || sending || !text.trim()) ? 'not-allowed' : 'pointer',
          opacity: (disabled || sending || !text.trim()) ? 0.5 : 1, fontFamily: 'inherit',
          display: 'inline-flex', alignItems: 'center', gap: 6,
        }}>
          {sending && <Spinner />}
          {sending ? '送信中' : '送信'}
        </button>
      </div>
      <div style={{ marginTop: 6, fontSize: 10, color: '#94a3b8', paddingLeft: 4 }}>エージェントは常に /brainstorm → /plan → /implement のパイプラインで動作します。</div>
    </div>
  );
}

function ChatPane({ task, messages, onSend, onOpenDetail, detailOpen, loading, onOpenCreate }) {
  const scrollRef = React.useRef(null);
  React.useEffect(() => {
    if (scrollRef.current) scrollRef.current.scrollTop = scrollRef.current.scrollHeight;
  }, [messages.length, task && task.id]);

  if (!task) {
    return (
      <div style={{ display: 'flex', flexDirection: 'column', height: '100%', background: '#fff', justifyContent: 'center' }}>
        <EmptyState
          icon={<svg width="22" height="22" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round"><path d="M21 15a2 2 0 01-2 2H7l-4 4V5a2 2 0 012-2h14a2 2 0 012 2z"/></svg>}
          title="タスクを選択してください"
          hint="左のリストから会話を開くか、新しい依頼を作成できます。"
          action={onOpenCreate && (
            <button onClick={onOpenCreate} style={{
              padding: '8px 14px', borderRadius: 10, fontSize: 12, fontWeight: 700,
              background: '#2563eb', color: '#fff', border: 'none', cursor: 'pointer',
              fontFamily: 'inherit', display: 'inline-flex', alignItems: 'center', gap: 6,
            }}>
              <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2.5" strokeLinecap="round"><path d="M12 5v14M5 12h14"/></svg>
              新しい依頼
            </button>
          )}
        />
      </div>
    );
  }

  return (
    <div style={{ display: 'flex', flexDirection: 'column', height: '100%', background: '#fff' }}>
      <ChatHeader task={task} onOpenDetail={onOpenDetail} detailOpen={detailOpen} />
      <div ref={scrollRef} style={{
        flex: 1, overflowY: 'auto', padding: '16px 20px',
        display: 'flex', flexDirection: 'column', gap: 12, minHeight: 0,
      }}>
        {loading && (
          <>
            <div style={{ alignSelf: 'flex-end', width: '60%' }}><SkeletonLine height={40} style={{ borderRadius: 16 }} /></div>
            <div style={{ alignSelf: 'flex-start', width: '70%' }}><SkeletonLine height={56} style={{ borderRadius: 16 }} /></div>
            <div style={{ alignSelf: 'flex-start', width: '40%' }}><SkeletonLine height={32} style={{ borderRadius: 12 }} /></div>
          </>
        )}
        {!loading && messages.length === 0 && (
          <EmptyState
            compact
            title="まだメッセージがありません"
            hint="下の入力欄から依頼の詳細を送信してください。エージェントが /brainstorm から開始します。"
          />
        )}
        {!loading && messages.map((m, i) => (
          m.role === 'progress'
            ? <ProgressBubble key={i} text={m.content} />
            : <Bubble key={i} role={m.role} footer={m.footer}>{m.content}</Bubble>
        ))}
      </div>
      <Composer onSend={onSend} disabled={task.status === 'cancelled' || task.status === 'succeeded'} />
    </div>
  );
}

window.ChatPane = ChatPane;