/**
 * Sidebar — 左侧边栏
 *
 * 始终显示，包含会话列表、新建会话按钮、搜索。
 */

import { useState, useEffect } from 'react';
import { Box, Typography, Button, IconButton, TextField, Stack, Collapse, List, ListItemButton, ListItemIcon, ListItemText, Badge, Divider, Dialog, DialogTitle, DialogContent, DialogActions } from '@mui/material';
import Fuse from 'fuse.js';
import { Plus, Search, MessageSquare, Pin, Wrench, Database, ChevronDown, ChevronRight, Trash2 } from 'lucide-react';
import { useSessionStore, type Session } from '@renderer/stores/session-store';
import { useAgentStore } from '@renderer/stores/agent-store';
import { formatRelativeTime } from '@renderer/lib/formatters';
import { LAYOUT } from '@renderer/lib/constants';

export function Sidebar(): React.JSX.Element {
  const sessions = useSessionStore((s) => s.sessions);
  const currentSessionId = useSessionStore((s) => s.currentSessionId);
  const setCurrentSession = useSessionStore((s) => s.setCurrentSession);
  const loadSessionMessages = useAgentStore((s) => s.setCurrentSession);
  const searchQuery = useSessionStore((s) => s.searchQuery);
  const setSearchQuery = useSessionStore((s) => s.setSearchQuery);
  const agentStatus = useAgentStore((s) => s.agentStatus);

  useEffect(() => {
    if (window.metona?.sessions?.list) window.metona.sessions.list().then((list) => useSessionStore.getState().setSessions((list as any[]).map((s) => ({ id: s.id, title: s.title, createdAt: s.createdAt, updatedAt: s.updatedAt, messageCount: s.messageCount, pinned: s.pinned, archived: s.archived })))).catch(() => {});
  }, []);

  const filteredSessions = (() => {
    let list = sessions.filter((s) => !s.archived);
    if (searchQuery) { const fuse = new Fuse(list, { keys: ['title'], threshold: 0.4, ignoreLocation: true }); list = fuse.search(searchQuery).map((r) => r.item); }
    return list.sort((a, b) => a.pinned === b.pinned ? b.updatedAt - a.updatedAt : a.pinned ? -1 : 1);
  })();

  const handleNewSession = async () => {
    if (window.metona?.sessions?.create) {
      try {
        const r = await window.metona.sessions.create() as { id: string; title: string; createdAt: number; updatedAt: number; messageCount: number; pinned: boolean; archived: boolean };
        useSessionStore.getState().addSession({ id: r.id, title: r.title, createdAt: r.createdAt, updatedAt: r.updatedAt, messageCount: r.messageCount, pinned: r.pinned, archived: r.archived });
        setCurrentSession(r.id);
        loadSessionMessages(r.id);
        return;
      } catch {}
    }
    const newSession: Session = { id: `s_${Date.now()}`, title: '新会话', createdAt: Date.now(), updatedAt: Date.now(), messageCount: 0, pinned: false, archived: false };
    useSessionStore.getState().addSession(newSession);
    setCurrentSession(newSession.id);
    loadSessionMessages(newSession.id);
  };

  return (
    <Box component="aside" sx={{ flexShrink: 0, display: 'flex', flexDirection: 'column', overflow: 'hidden', bgcolor: 'background.paper', borderRight: 1, borderColor: 'divider', width: LAYOUT.SIDEBAR_WIDTH }}>
      <Box sx={{ p: 1.5, flex: 1, display: 'flex', flexDirection: 'column', overflow: 'hidden' }}>
        <Button variant="outlined" fullWidth size="small" onClick={handleNewSession} sx={{ mb: 1.5, fontSize: 12 }}>
          <Plus size={14} style={{ marginRight: 8 }} /> 新建会话
        </Button>

        <TextField
          size="small"
          value={searchQuery}
          onChange={(e) => setSearchQuery(e.target.value)}
          placeholder="搜索会话..."
          slotProps={{
            input: {
              startAdornment: <Search size={14} style={{ color: '#8b8fa7', marginRight: 8 }} />,
            },
          }}
          sx={{ mb: 1.5, '& .MuiOutlinedInput-root': { fontSize: 12, borderRadius: 1.5, height: 34 } }}
        />

        <Box sx={{ flex: 1, overflowY: 'auto' }}>
          {filteredSessions.length === 0 ? (
            <Typography variant="caption" sx={{ textAlign: 'center', py: 4, display: 'block', color: 'text.secondary' }}>{searchQuery ? '无匹配结果' : '暂无会话'}</Typography>
          ) : filteredSessions.map((session) => (
            <SessionItem key={session.id} session={session} isActive={session.id === currentSessionId} isAgentActive={session.id === currentSessionId && (agentStatus === 'thinking' || agentStatus === 'executing')} onClick={() => { setCurrentSession(session.id); loadSessionMessages(session.id); }} />
          ))}
        </Box>

        <Divider sx={{ mt: 'auto', mb: 1 }} />
        <ToolManagerPanel />
        <MemorySearchPanel />
      </Box>
    </Box>
  );
}

function SessionItem({ session, isActive, isAgentActive, onClick }: { session: Session; isActive: boolean; isAgentActive: boolean; onClick: () => void }) {
  const [showDeleteDialog, setShowDeleteDialog] = useState(false);

  const handleDelete = (e: React.MouseEvent) => {
    e.stopPropagation();
    setShowDeleteDialog(true);
  };

  const confirmDelete = () => {
    window.metona?.sessions.delete(session.id).catch(() => {});
    useSessionStore.getState().removeSession(session.id);
    setShowDeleteDialog(false);
  };

  return (
    <>
      <ListItemButton onClick={onClick} selected={isActive} dense sx={{ borderRadius: 1.5, mb: 0.25, px: 1.5, py: 0.75, borderRight: isActive ? '2px solid' : '2px solid transparent', borderColor: isActive ? 'primary.main' : 'transparent', '&:hover .delete-btn': { opacity: 1 } }}>
        <ListItemIcon sx={{ minWidth: 24 }}>
          {session.pinned ? <Pin size={10} style={{ color: '#818cf8' }} /> : isAgentActive ? <Badge color="success" variant="dot" sx={{ '& .MuiBadge-dot': { animation: 'pulse 2s infinite', width: 8, height: 8 } }}><MessageSquare size={12} style={{ color: '#8b8fa7' }} /></Badge> : <MessageSquare size={12} style={{ color: '#8b8fa7' }} />}
        </ListItemIcon>
        <ListItemText primary={<Typography variant="body2" sx={{ fontSize: 12, overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap', color: isActive ? 'text.primary' : 'text.secondary' }}>{session.title}</Typography>}
          secondary={<Typography variant="caption" sx={{ fontSize: 10 }}>{formatRelativeTime(session.updatedAt)}{session.messageCount > 0 ? ` · ${session.messageCount} 条` : ''}</Typography>}
        />
        <IconButton
          className="delete-btn"
          size="small"
          onClick={handleDelete}
          sx={{ opacity: 0, transition: 'opacity 150ms', color: 'text.disabled', '&:hover': { color: 'error.main' }, width: 20, height: 20 }}
        >
          <Trash2 size={12} />
        </IconButton>
      </ListItemButton>

      <Dialog open={showDeleteDialog} onClose={() => setShowDeleteDialog(false)} maxWidth="xs" fullWidth>
        <DialogTitle sx={{ fontSize: 14 }}>删除会话</DialogTitle>
        <DialogContent>
          <Typography variant="body2" sx={{ color: 'text.secondary' }}>
            确定删除会话「{session.title}」？此操作不可恢复。
          </Typography>
        </DialogContent>
        <DialogActions>
          <Button size="small" onClick={() => setShowDeleteDialog(false)} sx={{ color: 'text.secondary' }}>取消</Button>
          <Button size="small" color="error" variant="contained" onClick={confirmDelete}>删除</Button>
        </DialogActions>
      </Dialog>
    </>
  );
}

function ToolManagerPanel() {
  const [expanded, setExpanded] = useState(false);
  const tools = [
    { name: 'read_file', label: '读取文件', risk: 'SAFE' }, { name: 'write_file', label: '写入文件', risk: 'MEDIUM' },
    { name: 'list_directory', label: '列出目录', risk: 'SAFE' }, { name: 'search_files', label: '搜索文件', risk: 'SAFE' },
    { name: 'web_search', label: '网络搜索', risk: 'LOW' }, { name: 'web_extract', label: '网页抓取', risk: 'LOW' },
    { name: 'memory_store', label: '存储记忆', risk: 'MEDIUM' }, { name: 'memory_search', label: '搜索记忆', risk: 'SAFE' },
    { name: 'run_command', label: '执行命令', risk: 'HIGH' },
  ];
  const riskColors: Record<string, string> = { SAFE: 'success.main', LOW: 'info.main', MEDIUM: 'warning.main', HIGH: 'error.main' };
  return (
    <Box>
      <ListItemButton onClick={() => setExpanded(!expanded)} dense sx={{ borderRadius: 1, px: 1.5, py: 0.75 }}>
        <ListItemIcon sx={{ minWidth: 24 }}>{expanded ? <ChevronDown size={12} /> : <ChevronRight size={12} />}<Wrench size={12} style={{ marginLeft: 4 }} /></ListItemIcon>
        <ListItemText primary={<Typography variant="body2" sx={{ fontSize: 12 }}>工具管理</Typography>} />
        <Typography variant="caption" sx={{ color: 'success.main', fontSize: 10 }}>9 就绪</Typography>
      </ListItemButton>
      <Collapse in={expanded}>
        <List dense disablePadding sx={{ pl: 3 }}>
          {tools.map((t) => (
            <ListItemButton key={t.name} dense sx={{ py: 0.25, px: 1, borderRadius: 1 }}>
              <Box sx={{ width: 6, height: 6, borderRadius: '50%', bgcolor: riskColors[t.risk], mr: 1, flexShrink: 0 }} />
              <Typography variant="caption" sx={{ flex: 1, fontSize: 11, color: 'text.secondary' }}>{t.label}</Typography>
              <Typography variant="caption" sx={{ fontSize: 9, color: riskColors[t.risk] }}>{t.risk}</Typography>
            </ListItemButton>
          ))}
        </List>
      </Collapse>
    </Box>
  );
}

function MemorySearchPanel() {
  const [expanded, setExpanded] = useState(false);
  const [query, setQuery] = useState('');
  const [results, setResults] = useState<Array<{ id: string; type: string; content: string; importance: number }>>([]);
  const [searching, setSearching] = useState(false);
  const handleSearch = async () => { if (!query.trim() || !window.metona?.memory?.search) return; setSearching(true); try { setResults((await window.metona.memory.search(query, { topK: 5 })) as any); } catch { setResults([]); } setSearching(false); };
  return (
    <Box>
      <ListItemButton onClick={() => setExpanded(!expanded)} dense sx={{ borderRadius: 1, px: 1.5, py: 0.75 }}>
        <ListItemIcon sx={{ minWidth: 24 }}>{expanded ? <ChevronDown size={12} /> : <ChevronRight size={12} />}<Database size={12} style={{ marginLeft: 4 }} /></ListItemIcon>
        <ListItemText primary={<Typography variant="body2" sx={{ fontSize: 12 }}>记忆搜索</Typography>} />
      </ListItemButton>
      <Collapse in={expanded}>
        <Stack spacing={1} sx={{ pl: 3, pr: 1, pb: 1 }}>
          <Stack direction="row" spacing={0.5}>
            <TextField size="small" value={query} onChange={(e) => setQuery(e.target.value)} onKeyDown={(e) => { if (e.key === 'Enter') handleSearch(); }} placeholder="搜索记忆..." sx={{ flex: 1, '& .MuiInputBase-root': { fontSize: 11, height: 28 } }} />
            <Button variant="outlined" size="small" onClick={handleSearch} disabled={searching} sx={{ minWidth: 40, height: 28, fontSize: 10 }}>{searching ? '...' : '搜索'}</Button>
          </Stack>
          {results.length > 0 && (
            <Box sx={{ maxHeight: 200, overflowY: 'auto', display: 'flex', flexDirection: 'column', gap: 0.5 }}>
              {results.map((r) => (
                <Box key={r.id} sx={{ px: 1, py: 0.75, borderRadius: 1, bgcolor: 'background.default', fontSize: 10, color: 'text.secondary' }}>
                  <Stack direction="row" spacing={0.5} sx={{ mb: 0.25, alignItems: 'center' }}>
                    <Box sx={{ px: 0.5, borderRadius: 0.5, bgcolor: 'action.hover', color: 'primary.main', fontSize: 9 }}>{r.type}</Box>
                    <Typography variant="caption" sx={{ fontSize: 9 }}>重要度: {r.importance.toFixed(1)}</Typography>
                  </Stack>
                  <Typography variant="caption" sx={{ fontSize: 10, display: 'block', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>{r.content.slice(0, 100)}</Typography>
                </Box>
              ))}
            </Box>
          )}
        </Stack>
      </Collapse>
    </Box>
  );
}