/**
 * commands.js
 * Command-line interface for the Task Master CLI
 */

import { program } from 'commander';
import path from 'path';
import chalk from 'chalk';
import boxen from 'boxen';
import fs from 'fs';

import { CONFIG, log, readJSON } from './utils.js';
import {
  parsePRD,
  updateTasks,
  generateTaskFiles,
  setTaskStatus,
  listTasks,
  expandTask,
  expandAllTasks,
  clearSubtasks,
  addTask,
  analyzeTaskComplexity
} from './task-manager.js';

import {
  addDependency,
  removeDependency,
  validateDependenciesCommand,
  fixDependenciesCommand
} from './dependency-manager.js';

import {
  displayBanner,
  displayHelp,
  displayNextTask,
  displayTaskById,
  displayComplexityReport,
} from './ui.js';

/**
 * Configure and register CLI commands
 * @param {Object} program - Commander program instance
 */
function registerCommands(programInstance) {
  // Default help
  programInstance.on('--help', function() {
    displayHelp();
  });
  
  // parse-prd command
  programInstance
    .command('parse-prd')
    .description('Parse a PRD file and generate tasks')
    .argument('[file]', 'Path to the PRD file')
    .option('-o, --output <file>', 'Output file path', 'tasks/tasks.json')
    .option('-n, --num-tasks <number>', 'Number of tasks to generate', '10')
    .action(async (file, options) => {
      if (!file) {
        console.log(chalk.yellow('No PRD file specified.'));
        console.log(boxen(
          chalk.white.bold('Parse PRD Help') + '\n\n' +
          chalk.cyan('Usage:') + '\n' +
          `  task-master parse-prd <prd-file.txt> [options]\n\n` +
          chalk.cyan('Options:') + '\n' +
          '  -o, --output <file>       Output file path (default: "tasks/tasks.json")\n' +
          '  -n, --num-tasks <number>  Number of tasks to generate (default: 10)\n\n' +
          chalk.cyan('Example:') + '\n' +
          '  task-master parse-prd requirements.txt --num-tasks 15\n\n' +
          chalk.yellow('Note: This command will generate tasks from a PRD document and will overwrite any existing tasks.json file.'),
          { padding: 1, borderColor: 'blue', borderStyle: 'round' }
        ));
        return;
      }
      
      const numTasks = parseInt(options.numTasks, 10);
      const outputPath = options.output;
      
      console.log(chalk.blue(`Parsing PRD file: ${file}`));
      console.log(chalk.blue(`Generating ${numTasks} tasks...`));
      
      await parsePRD(file, outputPath, numTasks);
    });

  // update command
  programInstance
    .command('update')
    .description('Update tasks based on new information or implementation changes')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .option('--from <id>', 'Task ID to start updating from (tasks with ID >= this value will be updated)', '1')
    .option('-p, --prompt <text>', 'Prompt explaining the changes or new context (required)')
    .option('-r, --research', 'Use Perplexity AI for research-backed task updates')
    .action(async (options) => {
      const tasksPath = options.file;
      const fromId = parseInt(options.from, 10);
      const prompt = options.prompt;
      const useResearch = options.research || false;
      
      if (!prompt) {
        console.error(chalk.red('Error: --prompt parameter is required. Please provide information about the changes.'));
        process.exit(1);
      }
      
      console.log(chalk.blue(`Updating tasks from ID >= ${fromId} with prompt: "${prompt}"`));
      console.log(chalk.blue(`Tasks file: ${tasksPath}`));
      
      if (useResearch) {
        console.log(chalk.blue('Using Perplexity AI for research-backed task updates'));
      }
      
      await updateTasks(tasksPath, fromId, prompt, useResearch);
    });

  // generate command
  programInstance
    .command('generate')
    .description('Generate task files from tasks.json')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .option('-o, --output <dir>', 'Output directory', 'tasks')
    .action(async (options) => {
      const tasksPath = options.file;
      const outputDir = options.output;
      
      console.log(chalk.blue(`Generating task files from: ${tasksPath}`));
      console.log(chalk.blue(`Output directory: ${outputDir}`));
      
      await generateTaskFiles(tasksPath, outputDir);
    });

  // set-status command
  programInstance
    .command('set-status')
    .description('Set the status of a task')
    .option('-i, --id <id>', 'Task ID (can be comma-separated for multiple tasks)')
    .option('-s, --status <status>', 'New status (todo, in-progress, review, done)')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .action(async (options) => {
      const tasksPath = options.file;
      const taskId = options.id;
      const status = options.status;
      
      if (!taskId || !status) {
        console.error(chalk.red('Error: Both --id and --status are required'));
        process.exit(1);
      }
      
      console.log(chalk.blue(`Setting status of task(s) ${taskId} to: ${status}`));
      
      await setTaskStatus(tasksPath, taskId, status);
    });

  // list command
  programInstance
    .command('list')
    .description('List all tasks')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .option('-s, --status <status>', 'Filter by status')
    .option('--with-subtasks', 'Show subtasks for each task')
    .action(async (options) => {
      const tasksPath = options.file;
      const statusFilter = options.status;
      const withSubtasks = options.withSubtasks || false;
      
      console.log(chalk.blue(`Listing tasks from: ${tasksPath}`));
      if (statusFilter) {
        console.log(chalk.blue(`Filtering by status: ${statusFilter}`));
      }
      if (withSubtasks) {
        console.log(chalk.blue('Including subtasks in listing'));
      }
      
      await listTasks(tasksPath, statusFilter, withSubtasks);
    });

  // expand command
  programInstance
    .command('expand')
    .description('Break down tasks into detailed subtasks')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .option('-i, --id <id>', 'Task ID to expand')
    .option('-a, --all', 'Expand all tasks')
    .option('-n, --num <number>', 'Number of subtasks to generate', CONFIG.defaultSubtasks.toString())
    .option('--research', 'Enable Perplexity AI for research-backed subtask generation')
    .option('-p, --prompt <text>', 'Additional context to guide subtask generation')
    .option('--force', 'Force regeneration of subtasks for tasks that already have them')
    .action(async (options) => {
      const tasksPath = options.file;
      const idArg = options.id ? parseInt(options.id, 10) : null;
      const allFlag = options.all;
      const numSubtasks = parseInt(options.num, 10);
      const forceFlag = options.force;
      const useResearch = options.research === true;
      const additionalContext = options.prompt || '';
      
      // Debug log to verify the value
      log('debug', `Research enabled: ${useResearch}`);
      
      if (allFlag) {
        console.log(chalk.blue(`Expanding all tasks with ${numSubtasks} subtasks each...`));
        if (useResearch) {
          console.log(chalk.blue('Using Perplexity AI for research-backed subtask generation'));
        } else {
          console.log(chalk.yellow('Research-backed subtask generation disabled'));
        }
        if (additionalContext) {
          console.log(chalk.blue(`Additional context: "${additionalContext}"`));
        }
        await expandAllTasks(numSubtasks, useResearch, additionalContext, forceFlag);
      } else if (idArg) {
        console.log(chalk.blue(`Expanding task ${idArg} with ${numSubtasks} subtasks...`));
        if (useResearch) {
          console.log(chalk.blue('Using Perplexity AI for research-backed subtask generation'));
        } else {
          console.log(chalk.yellow('Research-backed subtask generation disabled'));
        }
        if (additionalContext) {
          console.log(chalk.blue(`Additional context: "${additionalContext}"`));
        }
        await expandTask(idArg, numSubtasks, useResearch, additionalContext);
      } else {
        console.error(chalk.red('Error: Please specify a task ID with --id=<id> or use --all to expand all tasks.'));
      }
    });

  // analyze-complexity command
  programInstance
    .command('analyze-complexity')
    .description(`Analyze tasks and generate expansion recommendations${chalk.reset('')}`)
    .option('-o, --output <file>', 'Output file path for the report', 'scripts/task-complexity-report.json')
    .option('-m, --model <model>', 'LLM model to use for analysis (defaults to configured model)')
    .option('-t, --threshold <number>', 'Minimum complexity score to recommend expansion (1-10)', '5')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .option('-r, --research', 'Use Perplexity AI for research-backed complexity analysis')
    .action(async (options) => {
      const tasksPath = options.file || 'tasks/tasks.json';
      const outputPath = options.output;
      const modelOverride = options.model;
      const thresholdScore = parseFloat(options.threshold);
      const useResearch = options.research || false;
      
      console.log(chalk.blue(`Analyzing task complexity from: ${tasksPath}`));
      console.log(chalk.blue(`Output report will be saved to: ${outputPath}`));
      
      if (useResearch) {
        console.log(chalk.blue('Using Perplexity AI for research-backed complexity analysis'));
      }
      
      await analyzeTaskComplexity(options);
    });

  // clear-subtasks command
  programInstance
    .command('clear-subtasks')
    .description('Clear subtasks from specified tasks')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .option('-i, --id <ids>', 'Task IDs (comma-separated) to clear subtasks from')
    .option('--all', 'Clear subtasks from all tasks')
    .action(async (options) => {
      const tasksPath = options.file;
      const taskIds = options.id;
      const all = options.all;

      if (!taskIds && !all) {
        console.error(chalk.red('Error: Please specify task IDs with --id=<ids> or use --all to clear all tasks'));
        process.exit(1);
      }

      if (all) {
        // If --all is specified, get all task IDs
        const data = readJSON(tasksPath);
        if (!data || !data.tasks) {
          console.error(chalk.red('Error: No valid tasks found'));
          process.exit(1);
        }
        const allIds = data.tasks.map(t => t.id).join(',');
        clearSubtasks(tasksPath, allIds);
      } else {
        clearSubtasks(tasksPath, taskIds);
      }
    });

  // add-task command
  programInstance
    .command('add-task')
    .description('Add a new task using AI')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .option('-p, --prompt <text>', 'Description of the task to add (required)')
    .option('-d, --dependencies <ids>', 'Comma-separated list of task IDs this task depends on')
    .option('--priority <priority>', 'Task priority (high, medium, low)', 'medium')
    .action(async (options) => {
      const tasksPath = options.file;
      const prompt = options.prompt;
      const dependencies = options.dependencies ? options.dependencies.split(',').map(id => parseInt(id.trim(), 10)) : [];
      const priority = options.priority;
      
      if (!prompt) {
        console.error(chalk.red('Error: --prompt parameter is required. Please provide a task description.'));
        process.exit(1);
      }
      
      console.log(chalk.blue(`Adding new task with description: "${prompt}"`));
      console.log(chalk.blue(`Dependencies: ${dependencies.length > 0 ? dependencies.join(', ') : 'None'}`));
      console.log(chalk.blue(`Priority: ${priority}`));
      
      await addTask(tasksPath, prompt, dependencies, priority);
    });

  // next command
  programInstance
    .command('next')
    .description(`Show the next task to work on based on dependencies and status${chalk.reset('')}`)
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .action(async (options) => {
      const tasksPath = options.file;
      await displayNextTask(tasksPath);
    });

  // show command
  programInstance
    .command('show')
    .description(`Display detailed information about a specific task${chalk.reset('')}`)
    .argument('[id]', 'Task ID to show')
    .option('-i, --id <id>', 'Task ID to show')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .action(async (taskId, options) => {
      const idArg = taskId || options.id;
      
      if (!idArg) {
        console.error(chalk.red('Error: Please provide a task ID'));
        process.exit(1);
      }
      
      const tasksPath = options.file;
      await displayTaskById(tasksPath, idArg);
    });

  // add-dependency command
  programInstance
    .command('add-dependency')
    .description('Add a dependency to a task')
    .option('-i, --id <id>', 'Task ID to add dependency to')
    .option('-d, --depends-on <id>', 'Task ID that will become a dependency')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .action(async (options) => {
      const tasksPath = options.file;
      const taskId = options.id;
      const dependencyId = options.dependsOn;
      
      if (!taskId || !dependencyId) {
        console.error(chalk.red('Error: Both --id and --depends-on are required'));
        process.exit(1);
      }
      
      await addDependency(tasksPath, parseInt(taskId, 10), parseInt(dependencyId, 10));
    });

  // remove-dependency command
  programInstance
    .command('remove-dependency')
    .description('Remove a dependency from a task')
    .option('-i, --id <id>', 'Task ID to remove dependency from')
    .option('-d, --depends-on <id>', 'Task ID to remove as a dependency')
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .action(async (options) => {
      const tasksPath = options.file;
      const taskId = options.id;
      const dependencyId = options.dependsOn;
      
      if (!taskId || !dependencyId) {
        console.error(chalk.red('Error: Both --id and --depends-on are required'));
        process.exit(1);
      }
      
      await removeDependency(tasksPath, parseInt(taskId, 10), parseInt(dependencyId, 10));
    });

  // validate-dependencies command
  programInstance
    .command('validate-dependencies')
    .description(`Identify invalid dependencies without fixing them${chalk.reset('')}`)
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .action(async (options) => {
      await validateDependenciesCommand(options.file);
    });

  // fix-dependencies command
  programInstance
    .command('fix-dependencies')
    .description(`Fix invalid dependencies automatically${chalk.reset('')}`)
    .option('-f, --file <file>', 'Path to the tasks file', 'tasks/tasks.json')
    .action(async (options) => {
      await fixDependenciesCommand(options.file);
    });

  // complexity-report command
  programInstance
    .command('complexity-report')
    .description(`Display the complexity analysis report${chalk.reset('')}`)
    .option('-f, --file <file>', 'Path to the report file', 'scripts/task-complexity-report.json')
    .action(async (options) => {
      await displayComplexityReport(options.file);
    });
    
  // Add more commands as needed...
  
  return programInstance;
}

/**
 * Setup the CLI application
 * @returns {Object} Configured Commander program
 */
function setupCLI() {
  // Create a new program instance
  const programInstance = program
    .name('dev')
    .description('AI-driven development task management')
    .version(() => {
      // Read version directly from package.json
      try {
        const packageJsonPath = path.join(process.cwd(), 'package.json');
        if (fs.existsSync(packageJsonPath)) {
          const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
          return packageJson.version;
        }
      } catch (error) {
        // Silently fall back to default version
      }
      return CONFIG.projectVersion; // Default fallback
    })
    .helpOption('-h, --help', 'Display help')
    .addHelpCommand(false) // Disable default help command
    .on('--help', () => {
      displayHelp(); // Use your custom help display instead
    })
    .on('-h', () => {
      displayHelp();
      process.exit(0);
    });
  
  // Modify the help option to use your custom display
  programInstance.helpInformation = () => {
    displayHelp();
    return '';
  };
  
  // Register commands
  registerCommands(programInstance);
  
  return programInstance;
}

/**
 * Parse arguments and run the CLI
 * @param {Array} argv - Command-line arguments
 */
async function runCLI(argv = process.argv) {
  try {
    // Display banner if not in a pipe
    if (process.stdout.isTTY) {
      displayBanner();
    }
    
    // If no arguments provided, show help
    if (argv.length <= 2) {
      displayHelp();
      process.exit(0);
    }
    
    // Setup and parse
    const programInstance = setupCLI();
    await programInstance.parseAsync(argv);
  } catch (error) {
    console.error(chalk.red(`Error: ${error.message}`));
    
    if (CONFIG.debug) {
      console.error(error);
    }
    
    process.exit(1);
  }
}

export {
  registerCommands,
  setupCLI,
  runCLI
};