import { useState, useEffect, useCallback } from 'react';
import { useToasts } from '@geist-ui/core';
import {
  fetchFileList,
  fetchFileContent,
  saveFileContent,
  pullChanges,
  lookupFileByName,
} from '../services/api';
import { isImageFile } from '../utils/fileHelpers';

const DEFAULT_FILE = {
  name: 'New File.md',
  path: 'New File.md',
  content: '# Welcome to NovaMD\n\nStart editing here!',
};

const useFileManagement = (gitEnabled = false) => {
  const [content, setContent] = useState(DEFAULT_FILE.content);
  const [files, setFiles] = useState([]);
  const [selectedFile, setSelectedFile] = useState(DEFAULT_FILE.path);
  const [isNewFile, setIsNewFile] = useState(true);
  const [hasUnsavedChanges, setHasUnsavedChanges] = useState(false);
  const [error, setError] = useState(null);
  const { setToast } = useToasts();

  const loadFileList = useCallback(async () => {
    try {
      const fileList = await fetchFileList();
      if (Array.isArray(fileList)) {
        setFiles(fileList);
      } else {
        throw new Error('File list is not an array');
      }
    } catch (error) {
      console.error('Failed to load file list:', error);
      setError('Failed to load file list. Please try again later.');
    }
  }, []);

  const pullLatestChanges = useCallback(async () => {
    if (gitEnabled) {
      try {
        await pullChanges();
        setToast({
          text: 'Latest changes pulled successfully',
          type: 'success',
        });
        await loadFileList(); // Reload file list after pulling changes
      } catch (error) {
        console.error('Failed to pull latest changes:', error);
        setToast({
          text: 'Failed to pull latest changes: ' + error.message,
          type: 'error',
        });
      }
    }
  }, [gitEnabled, loadFileList, setToast]);

  useEffect(() => {
    const initializeFileSystem = async () => {
      if (gitEnabled) {
        await pullLatestChanges();
      } else {
        await loadFileList();
      }
    };

    initializeFileSystem();
  }, [gitEnabled]);

  const handleFileSelect = async (filePath) => {
    if (hasUnsavedChanges) {
      const confirmSwitch = window.confirm(
        'You have unsaved changes. Are you sure you want to switch files?'
      );
      if (!confirmSwitch) return;
    }

    try {
      if (!isImageFile(filePath)) {
        const fileContent = await fetchFileContent(filePath);
        setContent(fileContent);
      } else {
        setContent(''); // Set empty content for image files
      }
      setSelectedFile(filePath);
      setIsNewFile(false);
      setHasUnsavedChanges(false);
      setError(null);
    } catch (error) {
      console.error('Failed to load file content:', error);
      setError('Failed to load file content. Please try again.');
    }
  };

  const handleContentChange = (newContent) => {
    setContent(newContent);
    setHasUnsavedChanges(true);
  };

  const handleSave = useCallback(
    async (filePath, fileContent) => {
      try {
        await saveFileContent(filePath, fileContent);
        setToast({ text: 'File saved successfully', type: 'success' });
        setIsNewFile(false);
        setHasUnsavedChanges(false);
        if (isNewFile) {
          await loadFileList();
        }
      } catch (error) {
        console.error('Error saving file:', error);
        setToast({
          text: 'Failed to save file. Please try again.',
          type: 'error',
        });
      }
    },
    [setToast, isNewFile, loadFileList]
  );

  return {
    content,
    files,
    selectedFile,
    isNewFile,
    hasUnsavedChanges,
    error,
    handleFileSelect,
    handleContentChange,
    handleSave,
    pullLatestChanges,
    lookupFileByName,
  };
};

export default useFileManagement;