Terminal-based AI coding agent with interactive TUI for autonomous code generation.

Features:
  - Interactive TUI with React/Ink
  - Autonomous agent with tool calls (bash, read, write, edit, glob, grep)
  - Permission system with pattern-based rules
  - Session management with auto-compaction
  - Dual providers: GitHub Copilot and Ollama
  - MCP server integration
  - Todo panel and theme system
  - Streaming responses
  - GitHub-compatible project context

src/services/config.ts

@@ -0,0 +1,168 @@
+/**
+ * Configuration management for CodeTyper CLI
+ */
+
+import fs from "fs/promises";
+import path from "path";
+import type { Config, Provider } from "@/types/index";
+import { DIRS, FILES } from "@constants/paths";
+
+/**
+ * Default configuration values
+ */
+const getDefaults = (): Config => ({
+  provider: "copilot",
+  model: "auto",
+  theme: "default",
+  maxIterations: 20,
+  timeout: 30000,
+  cascadeEnabled: true,
+  protectedPaths: [
+    ".git",
+    "node_modules",
+    ".env",
+    ".env.local",
+    ".env.production",
+    "dist",
+    "build",
+    ".next",
+    "__pycache__",
+    "venv",
+    ".venv",
+  ],
+});
+
+/**
+ * Environment variable mapping for providers
+ */
+const PROVIDER_ENV_VARS: Record<Provider, string> = {
+  copilot: "GITHUB_COPILOT_TOKEN",
+  ollama: "OLLAMA_HOST",
+};
+
+/**
+ * Config state (singleton pattern using closure)
+ */
+let configState: Config = getDefaults();
+
+/**
+ * Load configuration from file
+ */
+export const loadConfig = async (): Promise<void> => {
+  try {
+    const data = await fs.readFile(FILES.config, "utf-8");
+    const loaded = JSON.parse(data);
+
+    // Clean up deprecated keys
+    delete loaded.models;
+
+    configState = { ...getDefaults(), ...loaded };
+  } catch {
+    // Config file doesn't exist or is invalid, use defaults
+    configState = getDefaults();
+  }
+};
+
+/**
+ * Save configuration to file
+ */
+export const saveConfig = async (): Promise<void> => {
+  try {
+    await fs.mkdir(DIRS.config, { recursive: true });
+    await fs.writeFile(
+      FILES.config,
+      JSON.stringify(configState, null, 2),
+      "utf-8",
+    );
+  } catch (error) {
+    throw new Error(`Failed to save config: ${error}`);
+  }
+};
+
+/**
+ * Get configuration value
+ */
+export const getConfigValue = <K extends keyof Config>(key: K): Config[K] => {
+  return configState[key];
+};
+
+/**
+ * Set configuration value
+ */
+export const setConfigValue = <K extends keyof Config>(
+  key: K,
+  value: Config[K],
+): void => {
+  configState[key] = value;
+};
+
+/**
+ * Get full configuration
+ */
+export const getAllConfig = (): Config => ({ ...configState });
+
+/**
+ * Get API key for provider from environment
+ */
+export const getApiKey = (provider?: Provider): string | undefined => {
+  const targetProvider = provider ?? configState.provider;
+  const envVar = PROVIDER_ENV_VARS[targetProvider];
+  return envVar ? process.env[envVar] : undefined;
+};
+
+/**
+ * Get configured model
+ */
+export const getModel = (): string => {
+  return configState.model ?? "auto";
+};
+
+/**
+ * Get config file path
+ */
+export const getConfigPath = (): string => FILES.config;
+
+/**
+ * Check if a path is protected
+ */
+export const isProtectedPath = (filePath: string): boolean => {
+  const normalizedPath = path.normalize(filePath);
+  return configState.protectedPaths.some((protectedPath) =>
+    normalizedPath.includes(protectedPath),
+  );
+};
+
+/**
+ * Reset configuration to defaults
+ */
+export const resetConfig = (): void => {
+  configState = getDefaults();
+};
+
+/**
+ * Initialize and get config (convenience function)
+ */
+export const getConfig = async (): Promise<{
+  get: <K extends keyof Config>(key: K) => Config[K];
+  set: <K extends keyof Config>(key: K, value: Config[K]) => void;
+  getAll: () => Config;
+  save: () => Promise<void>;
+  getApiKey: (provider?: Provider) => string | undefined;
+  getModel: () => string;
+  getConfigPath: () => string;
+  isProtectedPath: (filePath: string) => boolean;
+  reset: () => void;
+}> => {
+  await loadConfig();
+  return {
+    get: getConfigValue,
+    set: setConfigValue,
+    getAll: getAllConfig,
+    save: saveConfig,
+    getApiKey,
+    getModel,
+    getConfigPath,
+    isProtectedPath,
+    reset: resetConfig,
+  };
+};