import * as path from 'path';
import * as fs from 'fs-extra';
import { Command } from 'commander';
import ora from 'ora';
import chalk from 'chalk';
import {
  createWorktree,
  createGit,
  getMainBranch
} from '../utils/git-utils';
import {
  loadGlobalConfig,
  saveWorkspaceConfig,
  getWorkspacePath,
  isValidAgentName,
  detectPackageJson,
  installDependencies,
  getGitUserInfo
} from '../utils/file-utils';
import { setupEnvironment, runCustomSetupScript } from '../utils/env-utils';
import { sanitizeAgentName } from '../utils/file-utils';
import { GitAgentSyncError, InvalidAgentNameError } from '../utils/errors';
import { CreateOptions } from '../types';

export function createCreateCommand(): Command {
  const cmd = new Command('create')
    .description('Create an isolated git worktree for an AI agent')
    .argument('<agent-name>', 'Name identifier for the agent (will become agent-{name})')
    .option('-p, --path <path>', 'Custom path for the workspace')
    .option('-t, --template <template>', 'Path to environment template directory')
    .option('--no-install', 'Skip automatic dependency installation')
    .option('--env <key=value>', 'Set environment variable (can be used multiple times)', collectEnvVars)
    .action(async (agentName, options) => {
      try {
        const sanitizedName = sanitizeAgentName(agentName);

        if (!isValidAgentName(sanitizedName)) {
          throw new InvalidAgentNameError(agentName);
        }

        const currentPath = process.cwd();
        const spinner = ora('Initializing...').start();

        const globalConfig = await loadGlobalConfig();
        const branchName = `agent-${sanitizedName}`;
        const workspacePath = options.path
          ? path.resolve(currentPath, options.path)
          : getWorkspacePath(currentPath, sanitizedName);

        spinner.text = 'Checking git repository...';
        const git = createGit(currentPath);

        try {
          await git.raw(['rev-parse', '--is-inside-work-tree']);
        } catch {
          throw new GitAgentSyncError('Not a git repository. Please run this command from within a git repository.');
        }

        spinner.text = 'Checking workspace existence...';
        if (await fs.pathExists(workspacePath)) {
          throw new GitAgentSyncError(`Workspace already exists at ${workspacePath}. Use a different agent name or destroy the existing workspace first.`);
        }

        spinner.text = 'Determining main branch...';
        const mainBranch = await getMainBranch(git, globalConfig.defaultBranch);

        spinner.text = 'Creating worktree...';
        await createWorktree(currentPath, workspacePath, branchName, mainBranch);

        const gitUserInfo = await getGitUserInfo();

        const createOptions: CreateOptions = {
          path: options.path,
          template: options.template,
          installDeps: options.install !== false,
          environment: parseEnvVars(options.env || [])
        };

        spinner.text = 'Setting up environment...';
        await setupEnvironment(workspacePath, sanitizedName, createOptions);

        if (createOptions.installDeps) {
          spinner.text = 'Checking for dependencies...';
          if (await detectPackageJson(workspacePath)) {
            spinner.text = 'Installing dependencies...';
            await installDependencies(workspacePath);
          }
        }

        const workspaceConfig = {
          agentName: sanitizedName,
          branch: branchName,
          createdAt: new Date().toISOString(),
          mainBranch,
          environment: {
            AGENT_ID: sanitizedName,
            WORKSPACE_PATH: workspacePath,
            GIT_USER_EMAIL: gitUserInfo.email,
            GIT_USER_NAME: gitUserInfo.name
          }
        };

        await saveWorkspaceConfig(workspacePath, workspaceConfig);

        spinner.succeed(chalk.green('Workspace created successfully!'));

        console.log(chalk.cyan('\n📁 Workspace Details:'));
        console.log(`   Agent Name: ${chalk.white(sanitizedName)}`);
        console.log(`   Branch: ${chalk.white(branchName)}`);
        console.log(`   Path: ${chalk.white(workspacePath)}`);
        console.log(`   Main Branch: ${chalk.white(mainBranch)}`);
        console.log(`   Created: ${chalk.white(new Date().toISOString())}`);
        console.log(chalk.cyan('\n📝 Next Steps:'));
        console.log(`   1. ${chalk.white(`cd ${workspacePath}`)}`);
        console.log(`   2. ${chalk.white('Start your coding tasks')}`);
        console.log(`   3. ${chalk.white('git-agent-sync status')} - Track changes`);
        console.log(`   4. ${chalk.white('git-agent-sync diff')} - Generate diffs`);
        console.log(`   5. ${chalk.white('git-agent-sync merge')} - Merge back to main`);

      } catch (error) {
        const gitError = error instanceof GitAgentSyncError ? error : new GitAgentSyncError(String(error));
        console.error(chalk.red(`\n❌ Error: ${gitError.message}`));
        process.exit(1);
      }
    });

  return cmd;
}

function collectEnvVars(value: string, previous: string[]): string[] {
  return [...(previous || []), value];
}

function parseEnvVars(envVars: string[]): Record<string, string> {
  const result: Record<string, string> = {};

  for (const envVar of envVars) {
    const [key, ...valueParts] = envVar.split('=');
    if (key && valueParts.length > 0) {
      result[key] = valueParts.join('=');
    }
  }

  return result;
}