import React, { useState } from 'react';
import {
  Table,
  TableBody,
  TableCell,
  TableContainer,
  TableHead,
  TableRow,
  Paper,
  IconButton,
  Checkbox,
  Button,
  Chip,
  Dialog,
  DialogTitle,
  DialogContent,
  DialogActions,
  Typography,
  Tooltip,
} from '@mui/material';
import { Download as DownloadIcon, Delete as DeleteIcon, Error as ErrorIcon } from '@mui/icons-material';
import { File, FileStatus } from '../types/file';
import { api } from '../services/api';

interface FileListProps {
  files: File[];
  onFileStatusChange: () => void;
}

const FileList: React.FC<FileListProps> = ({ files, onFileStatusChange }) => {
  const [selectedFiles, setSelectedFiles] = useState<string[]>([]);
  const [deleteDialogOpen, setDeleteDialogOpen] = useState(false);
  const [fileToDelete, setFileToDelete] = useState<string | null>(null);

  const handleSelectFile = (fileId: string) => {
    setSelectedFiles((prev) =>
      prev.includes(fileId)
        ? prev.filter((id) => id !== fileId)
        : [...prev, fileId]
    );
  };

  const handleSelectAll = () => {
    setSelectedFiles((prev) =>
      prev.length === files.length ? [] : files.map((file) => file.id)
    );
  };

  const handleDownload = async (fileId: string) => {
    try {
      console.log('=== FRONTEND DOWNLOAD START ===');
      console.log('File ID:', fileId);
      
      const file = files.find((f) => f.id === fileId);
      console.log('File object:', file);
      
      const blob = await api.downloadFile(fileId);
      console.log('Blob received:', blob);
      console.log('Blob type:', blob.type);
      console.log('Blob size:', blob.size);
      
      const url = window.URL.createObjectURL(blob);
      const a = document.createElement('a');
      a.href = url;
      
      // Match backend behavior: change extension to .md
      const originalFilename = file?.filename || 'downloaded-file';
      const filenameWithoutExt = originalFilename.replace(/\.[^/.]+$/, ''); // Remove extension
      const downloadFilename = `${filenameWithoutExt}.md`;
      
      console.log('Original filename:', originalFilename);
      console.log('Filename without extension:', filenameWithoutExt);
      console.log('Download filename:', downloadFilename);
      
      a.download = downloadFilename;
      document.body.appendChild(a);
      a.click();
      window.URL.revokeObjectURL(url);
      document.body.removeChild(a);
      
      console.log('=== FRONTEND DOWNLOAD END ===');
    } catch (error) {
      console.error('Error downloading file:', error);
    }
  };

  const handleDownloadSelected = async () => {
    for (const fileId of selectedFiles) {
      await handleDownload(fileId);
    }
  };

  const handleDeleteClick = (fileId: string) => {
    setFileToDelete(fileId);
    setDeleteDialogOpen(true);
  };

  const handleDeleteConfirm = async () => {
    if (fileToDelete) {
      try {
        await api.deleteFile(fileToDelete);
        onFileStatusChange();
      } catch (error) {
        console.error('Error deleting file:', error);
      }
    }
    setDeleteDialogOpen(false);
    setFileToDelete(null);
  };

  const handleDeleteCancel = () => {
    setDeleteDialogOpen(false);
    setFileToDelete(null);
  };

  const getStatusColor = (status: FileStatus) => {
    switch (status) {
      case FileStatus.SUCCESS:
        return 'success';
      case FileStatus.FAILED:
        return 'error';
      case FileStatus.PROCESSING:
        return 'warning';
      default:
        return 'default';
    }
  };

  return (
    <div>
      <div style={{ marginBottom: '1rem' }}>
        <Button
          variant="contained"
          color="primary"
          onClick={handleDownloadSelected}
          disabled={selectedFiles.length === 0}
          sx={{ mr: 1 }}
        >
          Download Selected
        </Button>
      </div>
      <TableContainer component={Paper}>
        <Table>
          <TableHead>
            <TableRow>
              <TableCell padding="checkbox">
                <Checkbox
                  checked={selectedFiles.length === files.length}
                  indeterminate={selectedFiles.length > 0 && selectedFiles.length < files.length}
                  onChange={handleSelectAll}
                />
              </TableCell>
              <TableCell>Filename</TableCell>
              <TableCell>Status</TableCell>
              <TableCell>Created At</TableCell>
              <TableCell>Finished At</TableCell>
              <TableCell>Actions</TableCell>
            </TableRow>
          </TableHead>
          <TableBody>
            {files.map((file) => (
              <TableRow key={file.id}>
                <TableCell padding="checkbox">
                  <Checkbox
                    checked={selectedFiles.includes(file.id)}
                    onChange={() => handleSelectFile(file.id)}
                  />
                </TableCell>
                <TableCell>{file.filename}</TableCell>
                <TableCell>
                  <Chip
                    label={file.status}
                    color={getStatusColor(file.status) as any}
                    size="small"
                  />
                  {file.status === FileStatus.FAILED && file.error_message && (
                    <div style={{ marginTop: '4px' }}>
                      <Tooltip 
                        title={file.error_message}
                        placement="top-start"
                        arrow
                        sx={{ maxWidth: '400px' }}
                      >
                        <div 
                          style={{ 
                            display: 'flex', 
                            alignItems: 'flex-start', 
                            gap: '4px',
                            padding: '4px 8px',
                            backgroundColor: '#ffebee',
                            borderRadius: '4px',
                            border: '1px solid #ffcdd2'
                          }}
                        >
                          <ErrorIcon 
                            color="error" 
                            sx={{ fontSize: '16px', marginTop: '1px', flexShrink: 0 }} 
                          />
                          <Typography
                            variant="caption"
                            color="error"
                            sx={{
                              display: 'block',
                              wordBreak: 'break-word',
                              maxWidth: '300px',
                              lineHeight: '1.2',
                              cursor: 'help',
                              fontWeight: 500
                            }}
                          >
                            {file.error_message.length > 50 
                              ? `${file.error_message.substring(0, 50)}...` 
                              : file.error_message
                            }
                          </Typography>
                        </div>
                      </Tooltip>
                    </div>
                  )}
                </TableCell>
                <TableCell>
                  {new Date(file.created_at).toLocaleString()}
                </TableCell>
                <TableCell>
                  {(file.status === FileStatus.SUCCESS || file.status === FileStatus.FAILED)
                    ? new Date(file.updated_at).toLocaleString()
                    : '—'}
                </TableCell>
                <TableCell>
                  <IconButton
                    onClick={() => handleDeleteClick(file.id)}
                    size="small"
                    color="error"
                    sx={{ mr: 1 }}
                  >
                    <DeleteIcon />
                  </IconButton>
                  {file.status === FileStatus.SUCCESS && (
                    <IconButton
                      onClick={() => handleDownload(file.id)}
                      size="small"
                      color="primary"
                    >
                      <DownloadIcon />
                    </IconButton>
                  )}
                </TableCell>
              </TableRow>
            ))}
          </TableBody>
        </Table>
      </TableContainer>

      <Dialog
        open={deleteDialogOpen}
        onClose={handleDeleteCancel}
      >
        <DialogTitle>Confirm Delete</DialogTitle>
        <DialogContent>
          <Typography>
            Are you sure you want to delete this file? This action cannot be undone.
          </Typography>
        </DialogContent>
        <DialogActions>
          <Button onClick={handleDeleteCancel}>Cancel</Button>
          <Button onClick={handleDeleteConfirm} color="error" variant="contained">
            Delete
          </Button>
        </DialogActions>
      </Dialog>
    </div>
  );
};

export default FileList;