@fromsvenwithlove/devops-issues-cli/src/utils/stdin-state-manager.js

AI-powered CLI tool and library for Azure DevOps work item management with Claude agents

/**
 * Manages stdin state to prevent conflicts between different input handlers
 * This ensures proper isolation between keypress and inquirer
 */
class StdinStateManager {
  constructor() {
    this.originalState = null;
    this.savedListeners = new Map();
  }

  /**
   * Save the current state of stdin
   */
  saveState() {
    if (!process.stdin.isTTY) {
      return;
    }

    this.originalState = {
      rawMode: process.stdin.isRaw || false,
      paused: process.stdin.isPaused(),
      encoding: process.stdin.readableEncoding,
      listeners: new Map(),
    };

    // Save all event listeners
    const events = ["data", "keypress", "end", "error", "close"];
    events.forEach((event) => {
      const listeners = process.stdin.listeners(event);
      if (listeners.length > 0) {
        this.originalState.listeners.set(event, listeners.slice());
      }
    });
  }

  /**
   * Restore stdin to its original state
   */
  restoreState() {
    if (!this.originalState || !process.stdin.isTTY) {
      return;
    }

    // Remove all current listeners
    process.stdin.removeAllListeners();

    // Restore original listeners
    this.originalState.listeners.forEach((listeners, event) => {
      listeners.forEach((listener) => {
        process.stdin.on(event, listener);
      });
    });

    // Restore encoding
    if (this.originalState.encoding) {
      process.stdin.setEncoding(this.originalState.encoding);
    }

    // Restore raw mode and pause state
    if (process.stdin.setRawMode) {
      try {
        process.stdin.setRawMode(this.originalState.rawMode);
      } catch (e) {
        // Ignore errors if stdin is no longer in a valid state
      }
    }

    if (this.originalState.paused) {
      process.stdin.pause();
    } else {
      process.stdin.resume();
    }

    this.originalState = null;
  }

  /**
   * Fully reset stdin to a clean state for inquirer
   */
  resetForInquirer() {
    if (!process.stdin.isTTY) {
      return;
    }

    // Remove all keypress-related listeners
    process.stdin.removeAllListeners("keypress");

    // Ensure stdin is not in raw mode for inquirer
    if (process.stdin.setRawMode) {
      try {
        process.stdin.setRawMode(false);
      } catch (e) {
        // Ignore errors
      }
    }

    // Pause first to ensure clean state
    process.stdin.pause();

    // Clear any buffered input
    if (process.stdin.read) {
      while (process.stdin.read() !== null) {
        // Drain any buffered input
      }
    }

    // 🔧 IMPORTANT: resume stdin so Inquirer can listen cleanly
    process.stdin.resume();
  }

  /**
   * Check if stdin has been modified from its default state
   */
  isModified() {
    if (!process.stdin.isTTY) {
      return false;
    }

    // Check for keypress listeners (indicator of keypress module usage)
    const keypressListeners = process.stdin.listeners("keypress");
    return keypressListeners.length > 0;
  }
}

// Export singleton instance
export const stdinStateManager = new StdinStateManager();