import React, { useCallback, useEffect, useMemo, useState } from 'react';
import { ThemeProvider, createTheme, useMediaQuery, Box, Grid, Card, CardContent, CardActions, Typography, Button, TextField, Dialog, DialogTitle, DialogContent, DialogActions, IconButton, styled } from '@mui/material';
import EditIcon from '@mui/icons-material/Edit';
import DeleteIcon from '@mui/icons-material/Delete';
import AddIcon from '@mui/icons-material/Add';
import { useTLDraw } from '../../../../../contexts/TLDrawContext';
import { useAuth } from '../../../../../contexts/AuthContext';

type Cabinet = { id: string; name: string };

const Toolbar = styled('div')(() => ({ display: 'flex', gap: '8px', marginBottom: '8px' }));

export const CCCabinetsPanel: React.FC = () => {
  const { tldrawPreferences } = useTLDraw() as { tldrawPreferences?: { colorScheme?: 'light' | 'dark' | 'system' } };
  const { user: authUser, accessToken } = useAuth();
  const prefersDarkMode = useMediaQuery('(prefers-color-scheme: dark)');
  const [cabinets, setCabinets] = useState<Cabinet[]>([]);
  const [createOpen, setCreateOpen] = useState(false);
  const [renameOpen, setRenameOpen] = useState<null | Cabinet>(null);
  const [newName, setNewName] = useState('');

  const theme = useMemo(() => {
    const mode = (tldrawPreferences?.colorScheme === 'system')
      ? (prefersDarkMode ? 'dark' : 'light')
      : (tldrawPreferences?.colorScheme === 'dark' ? 'dark' : 'light');
    return createTheme({ palette: { mode, divider: 'var(--color-divider)' } });
  }, [tldrawPreferences?.colorScheme, prefersDarkMode]);

  const API_BASE: string = import.meta.env.VITE_API_BASE || '/api';

  type RequestInitLite = { method?: string; body?: string | FormData | Blob | null; headers?: Record<string, string> } | undefined;
  const apiFetch = useCallback(async (url: string, init?: RequestInitLite) => {
    const fullUrl = url.startsWith('http') ? url : `${API_BASE}${url}`;
    const res = await fetch(fullUrl, {
      ...init,
      headers: {
        'Authorization': `Bearer ${accessToken || ''}`,
        ...(init?.headers || {})
      }
    });
    if (!res.ok) throw new Error(await res.text());
    return res.json();
  }, [accessToken, API_BASE]);

  const loadCabinets = useCallback(async () => {
    const data = await apiFetch('/database/cabinets');
    setCabinets([...(data.owned || []), ...(data.shared || [])]);
  }, [apiFetch]);

  useEffect(() => {
    if (authUser?.id) {
      loadCabinets();
    }
  }, [loadCabinets, authUser?.id]);

  const handleCreate = async () => {
    if (!newName.trim()) return;
    await apiFetch('/database/cabinets', { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ name: newName }) });
    setNewName('');
    setCreateOpen(false);
    await loadCabinets();
  };

  const handleRename = async () => {
    if (!renameOpen || !newName.trim()) return;
    await apiFetch(`/database/cabinets/${renameOpen.id}`, { method: 'PATCH', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ name: newName }) });
    setRenameOpen(null);
    setNewName('');
    await loadCabinets();
  };

  const handleDelete = async (cabinetId: string) => {
    await apiFetch(`/database/cabinets/${cabinetId}`, { method: 'DELETE' });
    await loadCabinets();
  };

  return (
    <ThemeProvider theme={theme}>
      <Box sx={{ p: 1, height: '100%', display: 'flex', flexDirection: 'column', gap: 1 }}>
        <Toolbar>
          <Button size="small" variant="outlined" startIcon={<AddIcon />} onClick={() => { setNewName(''); setCreateOpen(true); }}>New Cabinet</Button>
        </Toolbar>
        <Grid container spacing={1} sx={{ overflow: 'auto' }}>
          {cabinets.map(c => (
            <Grid item xs={12} key={c.id}>
              <Card variant="outlined">
                <CardContent sx={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center' }}>
                  <div>
                    <Typography variant="subtitle1" sx={{ color: 'var(--color-text)' }}>{c.name}</Typography>
                    <Typography variant="caption" sx={{ color: 'var(--color-text-secondary)' }}>{c.id}</Typography>
                  </div>
                  <CardActions>
                    <IconButton size="small" onClick={() => { setRenameOpen(c); setNewName(c.name); }} title="Rename">
                      <EditIcon />
                    </IconButton>
                    <IconButton size="small" onClick={() => handleDelete(c.id)} title="Delete">
                      <DeleteIcon />
                    </IconButton>
                  </CardActions>
                </CardContent>
              </Card>
            </Grid>
          ))}
        </Grid>

        <Dialog open={createOpen} onClose={() => setCreateOpen(false)}>
          <DialogTitle>Create Cabinet</DialogTitle>
          <DialogContent>
            <TextField autoFocus fullWidth label="Name" value={newName} onChange={(e) => setNewName(e.target.value)} />
          </DialogContent>
          <DialogActions>
            <Button onClick={() => setCreateOpen(false)}>Cancel</Button>
            <Button onClick={handleCreate} disabled={!newName.trim()}>Create</Button>
          </DialogActions>
        </Dialog>

        <Dialog open={!!renameOpen} onClose={() => setRenameOpen(null)}>
          <DialogTitle>Rename Cabinet</DialogTitle>
          <DialogContent>
            <TextField autoFocus fullWidth label="New name" value={newName} onChange={(e) => setNewName(e.target.value)} />
          </DialogContent>
          <DialogActions>
            <Button onClick={() => setRenameOpen(null)}>Cancel</Button>
            <Button onClick={handleRename} disabled={!newName.trim()}>Save</Button>
          </DialogActions>
        </Dialog>
      </Box>
    </ThemeProvider>
  );
};