Task System

/**
 * Register a basic task that executes a single function
 * @param {string} name - Task name used for CLI execution
 * @param {string} [info] - Optional task description for help
 * @param {function} fn - Task function to execute
 */
grunt.registerTask = function(name, info, fn) {};

/**
 * Register a multi-task that can have multiple targets
 * @param {string} name - Task name used for CLI execution
 * @param {string} [info] - Optional task description for help  
 * @param {function} fn - Task function executed for each target
 */
grunt.registerMultiTask = function(name, info, fn) {};

/**
 * Register an initialization task for project setup
 * @param {string} name - Task name
 * @param {string} [info] - Task description
 * @param {function} fn - Initialization function
 */
grunt.registerInitTask = function(name, info, fn) {};

/**
 * Rename an existing task
 * @param {string} oldname - Current task name
 * @param {string} newname - New task name
 */
grunt.renameTask = function(oldname, newname) {};

/**
 * Check if a task exists
 * @param {string} name - Task name to check
 * @returns {boolean} True if task exists
 */
grunt.task.exists = function(name) {};

/**
 * Check if a task is an alias task
 * @param {string} name - Task name to check
 * @returns {boolean} True if task is an alias
 */
grunt.task.isTaskAlias = function(name) {};

/**
 * Parse command-line arguments into task names
 * @param {Array} args - Command-line arguments
 * @returns {string[]} Array of task names
 */
grunt.task.parseArgs = function(args) {};

/**
 * Split argument string into individual arguments
 * @param {string} str - Argument string
 * @returns {string[]} Array of arguments
 */
grunt.task.splitArgs = function(str) {};

/**
 * Normalize multi-task file configuration
 * @param {object} data - File configuration data
 * @param {string} target - Target name
 * @returns {Array} Normalized file objects
 */
grunt.task.normalizeMultiTaskFiles = function(data, target) {};

// Basic task
grunt.registerTask('hello', 'Say hello', function() {
  grunt.log.writeln('Hello World!');
});

// Multi-task with targets
grunt.registerMultiTask('concat', 'Concatenate files', function() {
  const options = this.options({
    separator: '\n'
  });
  
  this.files.forEach(function(fileObj) {
    const src = fileObj.src.filter(function(filepath) {
      return grunt.file.exists(filepath);
    });
    
    const content = src.map(function(filepath) {
      return grunt.file.read(filepath);
    }).join(options.separator);
    
    grunt.file.write(fileObj.dest, content);
    grunt.log.writeln('File "' + fileObj.dest + '" created.');
  });
});

// Asynchronous task
grunt.registerTask('async-task', 'An async task', function() {
  const done = this.async();
  
  setTimeout(function() {
    grunt.log.writeln('Async operation completed');
    done();
  }, 1000);
});

/**
 * Load tasks from an npm module
 * @param {string} name - Module name (e.g., 'grunt-contrib-concat')
 */
grunt.loadNpmTasks = function(name) {};

/**
 * Load tasks from a directory
 * @param {string} tasksdir - Directory path containing task files
 */
grunt.loadTasks = function(tasksdir) {};

// Load tasks from npm module
grunt.loadNpmTasks('grunt-contrib-concat');
grunt.loadNpmTasks('grunt-contrib-uglify');

// Load custom tasks from directory
grunt.loadTasks('tasks');
grunt.loadTasks('./build/custom-tasks');

/**
 * Execute tasks programmatically
 * @param {string[]} tasks - Array of task names to execute
 * @param {object} [options] - Execution options
 * @param {function} [done] - Completion callback
 */
grunt.tasks = function(tasks, options, done) {};

/**
 * Add tasks to the execution queue
 * @param {...string} tasks - Task names to queue
 */
grunt.task.run = function(...tasks) {};

/**
 * Mark a position in the task queue
 */
grunt.task.mark = function() {};

/**
 * Clear tasks from queue
 * @param {object} [options] - Clear options
 * @param {boolean} [options.untilMarker] - Clear only until marker
 */
grunt.task.clearQueue = function(options) {};

/**
 * Start task execution
 * @param {object} [options] - Start options
 * @param {boolean} [options.asyncDone] - Use async completion
 */
grunt.task.start = function(options) {};

/**
 * Require that specified tasks have run successfully
 * @param {...string} tasks - Task names
 */
grunt.task.requires = function(...tasks) {};

/**
 * Run all targets for a multi-task
 * @param {string} taskname - Multi-task name
 * @param {string[]} [args] - Task arguments
 */
grunt.task.runAllTargets = function(taskname, args) {};

// Programmatic execution
grunt.tasks(['clean', 'concat', 'uglify'], {force: true}, function() {
  console.log('Build completed!');
});

// Inside a task, require other tasks to have run
grunt.registerTask('deploy', function() {
  grunt.task.requires('build test');
  // Deploy logic here
});

// Task context object (available as 'this' in task functions)
const taskContext = {
  /** 
   * Mark task as asynchronous and return completion callback
   * @returns {function} Callback to signal task completion
   */
  async: function() {},
  
  /**
   * Get task options merged with defaults
   * @param {object} [defaults] - Default option values
   * @returns {object} Merged options
   */
  options: function(defaults) {},
  
  /**
   * Require that other tasks have run successfully
   * @param {string} tasks - Space-separated task names
   */
  requires: function(tasks) {},
  
  /**
   * Require that configuration properties exist
   * @param {string} props - Space-separated property paths
   */
  requiresConfig: function(props) {},
  
  /** Current task name */
  name: string,
  
  /** Task name with arguments */
  nameArgs: string,
  
  /** Array of task arguments */
  args: Array,
  
  /** Object of arguments as boolean flags */
  flags: Object,
  
  /** Current target name (multi-tasks only) */
  target: string,
  
  /** Current target data (multi-tasks only) */
  data: any,
  
  /** Normalized files array (multi-tasks only) */
  files: Array,
  
  /** Flattened source files array (multi-tasks only) */
  filesSrc: Array,
  
  /** Number of errors logged during task execution */
  errorCount: number
};

grunt.registerMultiTask('process', function() {
  // Get options with defaults
  const options = this.options({
    encoding: 'utf8',
    separator: '\n'
  });
  
  // Check required configuration
  this.requiresConfig('process.' + this.target + '.files');
  
  // Access task properties
  grunt.log.writeln('Processing target: ' + this.target);
  grunt.log.writeln('Task arguments: ' + this.args.join(', '));
  
  // Process files
  this.files.forEach(function(fileObj) {
    // File processing logic
  });
  
  // Check for errors
  if (this.errorCount > 0) {
    grunt.fail.warn('Task completed with errors');
  }
});

// Asynchronous task
grunt.registerTask('fetch-data', function() {
  const done = this.async();
  
  // Async operation
  fetchRemoteData()
    .then(function(data) {
      grunt.file.write('data.json', JSON.stringify(data));
      done();
    })
    .catch(function(error) {
      grunt.fail.warn('Failed to fetch data: ' + error.message);
      done(false);
    });
});

// File object structure in multi-tasks
const fileObject = {
  /** Array of source file paths */
  src: Array,
  
  /** Destination file path */
  dest: string,
  
  /** Original file specification object */
  orig: Object
};

grunt.registerMultiTask('compile', function() {
  this.files.forEach(function(fileObj) {
    // Filter existing source files
    const validSrc = fileObj.src.filter(function(filepath) {
      if (!grunt.file.exists(filepath)) {
        grunt.log.warn('Source file "' + filepath + '" not found.');
        return false;
      }
      return true;
    });
    
    // Process each source file
    const compiled = validSrc.map(function(filepath) {
      const content = grunt.file.read(filepath);
      return compileContent(content);
    }).join('\n');
    
    // Write compiled output
    grunt.file.write(fileObj.dest, compiled);
    grunt.log.writeln('File "' + fileObj.dest + '" created.');
  });
});

/**
 * Log warning and optionally abort execution
 * @param {string|Error} error - Error message or Error object
 * @param {number} [errorcode] - Exit code
 */
grunt.warn = function(error, errorcode) {};

/**
 * Log fatal error and abort execution
 * @param {string|Error} error - Error message or Error object  
 * @param {number} [errorcode] - Exit code
 */
grunt.fatal = function(error, errorcode) {};

grunt.registerTask('validate', function() {
  if (!grunt.file.exists('config.json')) {
    grunt.fail.warn('Configuration file not found');
    return false;
  }
  
  try {
    const config = grunt.file.readJSON('config.json');
    if (!config.version) {
      grunt.fail.fatal('Configuration missing required version field');
    }
  } catch (e) {
    grunt.fail.fatal('Invalid configuration file: ' + e.message);
  }
});