/**
 * API Configuration & Key Resolution Service
 * 
 * Provides unified, hierarchical access to OpenRouter API credentials,
 * supporting browser LocalStorage overrides and environment variables.
 */

import { UserSettings } from '../types';

const SETTINGS_KEY = 'cognitive-clarity-settings';

export const DEFAULT_OPENROUTER_MODEL = 'google/gemini-3.8-flash';
export const DEFAULT_SUPERVISOR_MODEL = 'google/gemini-3.8-flash';

export function getStoredUserSettings(): Partial<UserSettings> {
  try {
    if (typeof localStorage === 'undefined') {
      return {};
    }
    const saved = localStorage.getItem(SETTINGS_KEY);
    return saved ? JSON.parse(saved) : {};
  } catch (e) {
    console.error("Failed to read user settings from localStorage", e);
    return {};
  }
}

/**
 * Returns the effective OpenRouter API Key.
 * Precedence:
 * 1. Explicit argument
 * 2. UserSettings in LocalStorage
 * 3. Vite environment variable (VITE_OPENROUTER_API_KEY)
 * 4. Node process environment variable (OPENROUTER_API_KEY)
 */
export function getOpenRouterApiKey(customKey?: string): string {
  if (customKey !== undefined) {
    return customKey.trim();
  }

  const stored = getStoredUserSettings();
  if (stored.openRouterApiKey && stored.openRouterApiKey.trim().length > 0) {
    return stored.openRouterApiKey.trim();
  }

  if (typeof process !== 'undefined' && process.env?.OPENROUTER_API_KEY !== undefined) {
    return process.env.OPENROUTER_API_KEY.trim();
  }

  if (typeof import.meta !== 'undefined' && import.meta.env?.VITE_OPENROUTER_API_KEY) {
    return (import.meta.env.VITE_OPENROUTER_API_KEY as string).trim();
  }

  return '';
}

/**
 * Checks if a valid OpenRouter API Key is configured.
 */
export function hasOpenRouterApiKey(): boolean {
  return getOpenRouterApiKey().length > 0;
}

/**
 * Returns the effective Google Gemini API Key.
 * Precedence:
 * 1. Explicit argument
 * 2. UserSettings in LocalStorage (geminiApiKey)
 * 3. Node process environment variable (GEMINI_API_KEY / API_KEY / VITE_GEMINI_API_KEY)
 * 4. Vite environment variable (VITE_GEMINI_API_KEY)
 */
export function getGeminiApiKey(customKey?: string): string {
  if (customKey !== undefined) {
    return customKey.trim();
  }

  const stored = getStoredUserSettings();
  if (stored.geminiApiKey && stored.geminiApiKey.trim().length > 0) {
    return stored.geminiApiKey.trim();
  }

  if (typeof process !== 'undefined') {
    if (process.env?.GEMINI_API_KEY !== undefined) return process.env.GEMINI_API_KEY.trim();
    if (process.env?.API_KEY !== undefined) return process.env.API_KEY.trim();
    if (process.env?.VITE_GEMINI_API_KEY !== undefined) return process.env.VITE_GEMINI_API_KEY.trim();
  }

  if (typeof import.meta !== 'undefined' && import.meta.env?.VITE_GEMINI_API_KEY) {
    return (import.meta.env.VITE_GEMINI_API_KEY as string).trim();
  }

  return '';
}

/**
 * Checks if a valid Google Gemini API Key is configured.
 */
export function hasGeminiApiKey(): boolean {
  return getGeminiApiKey().length > 0;
}