/**
 * Module resolution result
 */
export interface ModuleResolution {
  code: string;
  path: string;
  metadata?: Record<string, any>;
}

/**
 * Base interface for module resolvers
 * Implement this interface to provide custom module resolution
 */
export abstract class ModuleResolver {
  /**
   * Resolve a module path to its source code
   * @param modulePath - The module path to resolve (e.g., "./utils", "@wang/core", "https://...")
   * @param fromPath - The path of the importing module (for relative resolution)
   * @returns Promise resolving to module code and resolved path
   */
  abstract resolve(modulePath: string, fromPath?: string): Promise<ModuleResolution>;

  /**
   * Check if a module exists
   * @param modulePath - The module path to check
   * @param fromPath - The path of the importing module (for relative resolution)
   * @returns Promise resolving to true if module exists
   */
  abstract exists(modulePath: string, fromPath?: string): Promise<boolean>;

  /**
   * List available modules (for autocomplete/suggestions)
   * @param prefix - Optional prefix to filter modules
   * @returns Promise resolving to array of available module paths
   */
  abstract list(prefix?: string): Promise<string[]>;

  /**
   * Clear any caches (optional)
   */
  clearCache?(): void;

  /**
   * Get module metadata (optional)
   * @param modulePath - The module path
   * @returns Promise resolving to module metadata
   */
  getMetadata?(modulePath: string): Promise<Record<string, any> | null>;
}

/**
 * Helper to normalize module paths
 */
export function normalizePath(path: string): string {
  const parts = path.split('/');
  const normalized: string[] = [];

  for (const part of parts) {
    if (part === '..') {
      normalized.pop();
    } else if (part && part !== '.') {
      normalized.push(part);
    }
  }

  return normalized.join('/');
}

/**
 * Helper to resolve relative paths
 */
export function resolveRelativePath(modulePath: string, fromPath?: string): string {
  if (!fromPath || !modulePath.startsWith('.')) {
    return modulePath;
  }

  const basePath = fromPath.split('/').slice(0, -1).join('/');
  return normalizePath(basePath + '/' + modulePath);
}

/**
 * Helper to add file extension if missing
 */
export function addExtension(path: string, extension: string = '.wang'): string {
  if (path.endsWith(extension) || path.includes('.')) {
    return path;
  }
  return path + extension;
}