/**
 * AI Provider Configuration
 * Manages configuration for different AI providers (Claude, Ollama, Cloudflare)
 */

// Default configuration
const DEFAULT_PROVIDER = 'claude';
// Use 127.0.0.1 instead of localhost to avoid IPv6 resolution issues
const DEFAULT_OLLAMA_URL = 'http://127.0.0.1:11434';
const DEFAULT_CLOUDFLARE_ACCOUNT_ID = process.env.CLOUDFLARE_ACCOUNT_ID || '';

/**
 * Get the current AI provider
 * @returns {string} Provider name ('claude' or 'ollama')
 */
export function getProvider() {
    return process.env.AI_PROVIDER || DEFAULT_PROVIDER;
}

/**
 * Get Ollama API URL
 * @returns {string} Ollama base URL
 */
export function getOllamaUrl() {
    return process.env.OLLAMA_URL || DEFAULT_OLLAMA_URL;
}

/**
 * Get Anthropic API URL
 * @returns {string} Anthropic base URL
 */
export function getAnthropicUrl() {
    return process.env.ANTHROPIC_API_URL || 'https://api.anthropic.com';
}

/**
 * Get Cloudflare Account ID
 * @returns {string} Cloudflare account ID
 */
export function getCloudflareAccountId() {
    return process.env.CLOUDFLARE_ACCOUNT_ID || DEFAULT_CLOUDFLARE_ACCOUNT_ID;
}

/**
 * Get Cloudflare API Token
 * @returns {string} Cloudflare API token
 */
export function getCloudflareApiToken() {
    return process.env.CLOUDFLARE_API_TOKEN || '';
}

/**
 * Get Cloudflare Workers AI base URL
 * @returns {string} Cloudflare Workers AI base URL
 */
export function getCloudflareUrl() {
    const accountId = getCloudflareAccountId();
    return `https://api.cloudflare.com/client/v4/accounts/${accountId}/ai/run`;
}

/**
 * Get provider configuration for a specific provider
 * @param {string} provider - Provider name
 * @returns {object} Provider configuration
 */
export function getProviderConfig(provider) {
    switch (provider) {
        case 'ollama':
            return {
                name: 'ollama',
                baseUrl: getOllamaUrl(),
                chatEndpoint: '/api/chat',
                requiresAuth: false
            };
        case 'cloudflare':
            return {
                name: 'cloudflare',
                baseUrl: getCloudflareUrl(),
                chatEndpoint: '', // Model is appended to baseUrl
                requiresAuth: true,
                apiKey: getCloudflareApiToken(),
                accountId: getCloudflareAccountId()
            };
        case 'claude':
        default:
            return {
                name: 'claude',
                baseUrl: getAnthropicUrl(),
                chatEndpoint: '/v1/messages',
                requiresAuth: true,
                apiKey: process.env.ANTHROPIC_API_KEY
            };
    }
}

/**
 * Determine provider from model ID
 * @param {string} modelId - Model identifier
 * @returns {string} Provider name
 */
export function getProviderFromModel(modelId) {
    if (!modelId) return getProvider();

    // Claude models start with 'claude-'
    if (modelId.startsWith('claude-')) {
        return 'claude';
    }

    // Cloudflare models start with '@cf/' or '@hf/'
    if (modelId.startsWith('@cf/') || modelId.startsWith('@hf/')) {
        return 'cloudflare';
    }

    // Known Ollama models
    const ollamaModels = [
        'llama', 'mistral', 'qwen', 'codellama', 'phi',
        'gemma', 'neural-chat', 'starling', 'orca', 'vicuna',
        'deepseek', 'dolphin', 'nous-hermes', 'openhermes'
    ];

    for (const prefix of ollamaModels) {
        if (modelId.toLowerCase().startsWith(prefix)) {
            return 'ollama';
        }
    }

    // Default to configured provider
    return getProvider();
}

export default {
    getProvider,
    getOllamaUrl,
    getAnthropicUrl,
    getCloudflareAccountId,
    getCloudflareApiToken,
    getCloudflareUrl,
    getProviderConfig,
    getProviderFromModel
};