import { useState } from 'react';
import { History, MessageSquare, Plus, X } from 'lucide-react';
import type { Chat, WorkspacePane } from '@/api/types';
import {
  ContextMenu,
  ContextMenuContent,
  ContextMenuItem,
  ContextMenuSeparator,
  ContextMenuTrigger,
} from '@/components/ui/context-menu';
import { cn } from '@/lib/utils';

interface Props {
  pane: WorkspacePane;
  tabs: Chat[];
  onSwitchTab: (tabIdx: number) => void;
  onRemoveTab: (chatId: string) => void;
  onCloseOthers: (chatId: string) => void;
  onCloseToRight: (chatId: string) => void;
  onCloseAll: () => void;
  onNewChat: () => void;
  onShowHistory: () => void;
  onRename: (chatId: string, name: string) => Promise<void>;
  onRemovePane?: () => void;
}

export function ChatTabBar({
  pane,
  tabs,
  onSwitchTab,
  onRemoveTab,
  onCloseOthers,
  onCloseToRight,
  onCloseAll,
  onNewChat,
  onShowHistory,
  onRename,
  onRemovePane,
}: Props) {
  const [renamingId, setRenamingId] = useState<string | null>(null);
  const [renameValue, setRenameValue] = useState('');

  function startRename(chatId: string, currentName: string | null) {
    setRenamingId(chatId);
    setRenameValue(currentName ?? '');
  }

  async function finishRename() {
    if (renamingId && renameValue.trim()) {
      await onRename(renamingId, renameValue.trim());
    }
    setRenamingId(null);
  }

  return (
    <div className="flex items-center border-b border-border bg-muted/20 h-8 shrink-0 overflow-x-auto">
      {tabs.map((chat, tabIdx) => {
        const isActive = tabIdx === pane.activeChatIdx;
        const isLast = tabIdx === tabs.length - 1;
        const onlyTab = tabs.length === 1;
        const label = chat.name ?? 'New chat';
        return (
          <ContextMenu key={chat.id}>
            <ContextMenuTrigger asChild>
              <div
                onClick={() => onSwitchTab(tabIdx)}
                className={cn(
                  'group flex items-center gap-1.5 px-3 py-1.5 text-xs border-r border-border cursor-default select-none shrink-0',
                  isActive
                    ? 'bg-background text-foreground'
                    : 'bg-muted/30 text-muted-foreground hover:bg-muted/60'
                )}
              >
                <MessageSquare size={12} className="shrink-0" />
                {renamingId === chat.id ? (
                  <input
                    autoFocus
                    value={renameValue}
                    onChange={(e) => setRenameValue(e.target.value)}
                    onBlur={() => void finishRename()}
                    onKeyDown={(e) => {
                      if (e.key === 'Enter') void finishRename();
                      if (e.key === 'Escape') setRenamingId(null);
                    }}
                    onClick={(e) => e.stopPropagation()}
                    className="bg-transparent border-b border-border text-xs outline-none w-28"
                  />
                ) : (
                  <span className="truncate max-w-[140px]" title={label}>
                    {label}
                  </span>
                )}
                <button
                  type="button"
                  onClick={(e) => {
                    e.stopPropagation();
                    onRemoveTab(chat.id);
                  }}
                  className="p-0.5 hover:bg-muted rounded opacity-0 group-hover:opacity-60 hover:!opacity-100 shrink-0"
                  aria-label="Close tab"
                >
                  <X size={10} />
                </button>
              </div>
            </ContextMenuTrigger>
            <ContextMenuContent>
              <ContextMenuItem onSelect={() => startRename(chat.id, chat.name)}>
                Rename
              </ContextMenuItem>
              <ContextMenuSeparator />
              <ContextMenuItem onSelect={() => onRemoveTab(chat.id)}>
                Close
              </ContextMenuItem>
              <ContextMenuItem
                disabled={onlyTab}
                onSelect={() => onCloseOthers(chat.id)}
              >
                Close others
              </ContextMenuItem>
              <ContextMenuItem
                disabled={isLast}
                onSelect={() => onCloseToRight(chat.id)}
              >
                Close to right
              </ContextMenuItem>
              <ContextMenuItem onSelect={() => onCloseAll()}>
                Close all
              </ContextMenuItem>
            </ContextMenuContent>
          </ContextMenu>
        );
      })}

      {tabs.length === 0 && (
        <div className="flex items-center gap-1.5 px-3 py-1.5 text-xs text-muted-foreground">
          <History size={12} className="shrink-0" />
          <span>Session</span>
        </div>
      )}

      <div className="flex items-center ml-auto gap-0.5 px-1 shrink-0">
        <button
          type="button"
          onClick={onNewChat}
          className="p-1 rounded text-muted-foreground hover:bg-muted hover:text-foreground"
          aria-label="New chat"
          title="New chat"
        >
          <Plus size={12} />
        </button>
        <button
          type="button"
          onClick={onShowHistory}
          className={cn(
            'p-1 rounded text-muted-foreground hover:bg-muted hover:text-foreground',
            pane.kind === 'empty' && 'text-foreground bg-muted/50'
          )}
          aria-label="Session history"
          title="Session history"
        >
          <History size={12} />
        </button>
        {onRemovePane && (
          <button
            type="button"
            onClick={onRemovePane}
            className="p-1 rounded text-muted-foreground hover:bg-muted hover:text-foreground"
            aria-label="Close pane"
            title="Close pane"
          >
            <X size={12} />
          </button>
        )}
      </div>
    </div>
  );
}