module.exports = {
  root: true,
  parser: '@typescript-eslint/parser',
  parserOptions: {
    ecmaVersion: 2022,
    sourceType: 'module',
    project: './tsconfig.json',
    tsconfigRootDir: __dirname,
  },
  plugins: [
    '@typescript-eslint',
    'import',
    'prefer-arrow',
  ],
  extends: [
    'eslint:recommended',
    'plugin:@typescript-eslint/recommended',
    'plugin:@typescript-eslint/recommended-requiring-type-checking',
    'prettier', // Must be last to override other configs
  ],
  rules: {
    // TypeScript specific
    '@typescript-eslint/no-unused-vars': ['error', { argsIgnorePattern: '^_' }],
    '@typescript-eslint/explicit-function-return-type': 'warn',
    '@typescript-eslint/explicit-module-boundary-types': 'warn',
    '@typescript-eslint/no-explicit-any': 'error',
    '@typescript-eslint/no-non-null-assertion': 'off',
    '@typescript-eslint/prefer-nullish-coalescing': 'error',
    '@typescript-eslint/prefer-optional-chain': 'error',
    '@typescript-eslint/no-unnecessary-type-assertion': 'error',
    '@typescript-eslint/no-floating-promises': 'error',
    '@typescript-eslint/await-thenable': 'error',
    '@typescript-eslint/require-await': 'error',
    '@typescript-eslint/no-misused-promises': 'error',

    // Import rules
    'import/order': ['error', {
      'groups': [
        'builtin',
        'external',
        'internal',
        'parent',
        'sibling',
        'index',
      ],
      'pathGroups': [
        {
          'pattern': '#root/**',
          'group': 'internal',
          'position': 'before'
        }
      ],
      'pathGroupsExcludedImportTypes': ['builtin'],
      'newlines-between': 'never',
      'alphabetize': {
        'order': 'asc',
        'caseInsensitive': true
      }
    }],
    'import/no-unresolved': 'error',
    'import/extensions': ['error', 'always', {
      'ts': 'always',
      'js': 'always'
    }],

    // General code quality
    'no-console': 'off', // Allowed for game development
    'no-debugger': 'warn',
    'no-unused-vars': 'off', // Use TypeScript version instead
    'prefer-const': 'error',
    'no-var': 'error',
    'object-shorthand': 'error',
    'prefer-template': 'error',
    'prefer-arrow-callback': 'error',
    'arrow-body-style': ['error', 'as-needed'],

    // Stylistic (handled by Prettier, but some logical ones)
    'curly': ['error', 'all'],
    'brace-style': 'off', // Prettier handles this
    'comma-dangle': 'off', // Prettier handles this
    'quotes': 'off', // Prettier handles this
    'semi': 'off', // Prettier handles this

    // Best practices
    'eqeqeq': ['error', 'always'],
    'no-eval': 'error',
    'no-implied-eval': 'error',
    'no-new-wrappers': 'error',
    'no-throw-literal': 'error',
    'no-return-await': 'error',

    // Complexity
    'complexity': ['warn', 10],
    'max-lines': ['warn', { max: 500, skipBlankLines: true, skipComments: true }],
    'max-lines-per-function': ['warn', { max: 100, skipBlankLines: true, skipComments: true }],

    // Naming conventions
    '@typescript-eslint/naming-convention': [
      'error',
      {
        'selector': 'default',
        'format': ['PascalCase', 'camelCase']
      },
      {
        'selector': 'function',
        'format': ['PascalCase', 'camelCase']
      },
      {
        'selector': 'variable',
        'format': ['camelCase', 'UPPER_CASE', 'PascalCase'],
        'prefix': ['_', 'BP_', 'AC_', 'WBP_', 'UBP_', 'ABP_', 'IMC_', 'IA_', 'DT_', 'BFL_', 'U', 'A', 'T', 'F']
      },
      {
        'selector': 'variable',
        'format': ['camelCase', 'UPPER_CASE', 'PascalCase'],
        'filter': {
          'regex': '^(?!_|BP_|AC_|WBP_|UBP_|ABP_|IA_|DT_|IMC_|BFL_|U[A-Z]|A[A-Z]|T[A-Z]|F[A-Z])',
          'match': true
        }
      },
      // Unreal Engine classes with prefixes
      {
        'selector': 'class',
        'format': ['PascalCase'],
        'prefix': ['_', 'BP_', 'AC_', 'WBP_', 'UBP_', 'ABP_', 'IMC_', 'IA_', 'DT_', 'FT_', 'BFL_', 'U', 'A', 'T', 'F']
      },
      // Regular classes without prefix
      {
        'selector': 'class',
        'format': ['PascalCase'],
        'filter': {
          'regex': '^(?!_|BP_|AC_|WBP_|UBP_|ABP_|IA_|IMC_|BFL_|U[A-Z]|A[A-Z]|T[A-Z]|F[A-Z])',
          'match': true
        }
      },
      // Interfaces and Structs
      {
        'selector': 'interface',
        'format': ['PascalCase'],
        'prefix': ['S_', 'I_', 'I']
      },
      // Enums
      {
        'selector': 'enum',
        'format': ['PascalCase'],
        'prefix': ['E_', 'E']
      },
      {
        'selector': 'enumMember',
        'format': ['PascalCase']
      }
    ],

    '@typescript-eslint/no-unsafe-member-access': 'off'
  },
  settings: {
    'import/resolver': {
      'typescript': {
        'alwaysTryTypes': true,
        'project': './tsconfig.json'
      },
      'node': {
        'extensions': ['.js', '.ts', '.json']
      }
    },
    'import/parsers': {
      '@typescript-eslint/parser': ['.ts', '.tsx']
    }
  },
  env: {
    browser: true,
    es2022: true,
    node: true,
  },
  ignorePatterns: [
    'node_modules/',
    'dist/',
    'build/',
    '**/*.d.ts'
  ]
};