using System.Collections.Generic;

using AIRuntime.Runtime.Providers.OpenAI;


namespace AIRuntime.Runtime.Providers.OpenRouter
{
    /// <summary>
    /// OpenRouter provider using the OpenAI-compatible
    /// Chat Completions endpoint.
    /// </summary>
    public sealed class OpenRouterProvider :
        OpenAICompatibleProvider
    {
        public const string DefaultBaseUrl =
            "https://openrouter.ai/api/v1";


        public OpenRouterProvider(
            string apiKey,
            string model,
            string httpReferer = null,
            string applicationTitle = null,
            int timeoutSeconds = 60,
            string baseUrl = DefaultBaseUrl)
            : this(
                new OpenAIClient(
                    apiKey,
                    model,
                    baseUrl,
                    timeoutSeconds: timeoutSeconds,
                    providerName: "OpenRouter",
                    defaultHeaders: CreateHeaders(
                        httpReferer,
                        applicationTitle)))
        {
        }


        public OpenRouterProvider(
            IOpenAIClient client)
            : base(
                "OpenRouter",
                client)
        {
        }


        private static IReadOnlyDictionary<string, string>
            CreateHeaders(
                string httpReferer,
                string applicationTitle)
        {
            Dictionary<string, string> headers =
                new Dictionary<string, string>();


            if (!string.IsNullOrWhiteSpace(httpReferer))
            {
                headers.Add(
                    "HTTP-Referer",
                    httpReferer.Trim());
            }


            if (!string.IsNullOrWhiteSpace(applicationTitle))
            {
                headers.Add(
                    "X-OpenRouter-Title",
                    applicationTitle.Trim());
            }


            return headers;
        }
    }
}
