using BotSharp.Abstraction.MLTasks;
using BotSharp.Abstraction.MLTasks.Settings;
using BotSharp.Abstraction.Settings;

namespace BotSharp.Core.Infrastructures;

public class LlmProviderService : ILlmProviderService
{
    private readonly IServiceProvider _services;
    private readonly ILogger _logger;

    public LlmProviderService(IServiceProvider services, ILogger<LlmProviderService> logger)
    {
        _services = services;
        _logger = logger;
    }

    public List<string> GetProviders()
    {
        var providers = new List<string>();
        var services1 = _services.GetServices<ITextCompletion>();
        providers.AddRange(services1
            .Where(x => GetProviderModels(x.Provider).Any())
            .Select(x => x.Provider));

        var services2 = _services.GetServices<IChatCompletion>();
        providers.AddRange(services2
            .Where(x => GetProviderModels(x.Provider).Any())
            .Select(x => x.Provider));

        var services3 = _services.GetServices<ITextEmbedding>();
        providers.AddRange(services3
            .Where(x => GetProviderModels(x.Provider).Any())
            .Select(x => x.Provider));

        return providers.Distinct().ToList();
    }

    public List<LlmModelSetting> GetProviderModels(string provider)
    {
        var settingService = _services.GetRequiredService<ISettingService>();
        return settingService.Bind<List<LlmProviderSetting>>($"LlmProviders")
            .FirstOrDefault(x => x.Provider.Equals(provider))
            ?.Models ?? new List<LlmModelSetting>();
    }

    public LlmModelSetting GetProviderModel(string provider, string id, bool? multiModal = null, bool realTime = false, bool imageGenerate = false)
    {
        var models = GetProviderModels(provider)
            .Where(x => x.Id == id);

        if (multiModal.HasValue)
        {
            models = models.Where(x => x.MultiModal == multiModal);
        }

        models = models.Where(x => x.RealTime == realTime);

        models = models.Where(x => x.ImageGeneration == imageGenerate);

        var random = new Random();
        var index = random.Next(0, models.Count());
        var modelSetting = models.ElementAt(index);
        return modelSetting;
    }

    public LlmModelSetting? GetSetting(string provider, string model)
    {
        var settings = _services.GetRequiredService<List<LlmProviderSetting>>();
        var providerSetting = settings.FirstOrDefault(p => 
            p.Provider.Equals(provider, StringComparison.CurrentCultureIgnoreCase));
        if (providerSetting == null)
        {
            _logger.LogError($"Can't find provider settings for {provider}");
            return null;
        }        

        var modelSetting = providerSetting.Models.FirstOrDefault(m => 
            m.Name.Equals(model, StringComparison.CurrentCultureIgnoreCase));
        if (modelSetting == null)
        {
            _logger.LogError($"Can't find model settings for {provider}.{model}");
            return null;
        }

        // load balancing
        if (!string.IsNullOrEmpty(modelSetting.Group))
        {
            // find the models in the same group
            var models = providerSetting.Models
                .Where(m => !string.IsNullOrEmpty(m.Group) && 
                    m.Group.Equals(modelSetting.Group, StringComparison.CurrentCultureIgnoreCase))
                .ToList();

            // pick one model randomly
            var random = new Random();
            var index = random.Next(0, models.Count());
            modelSetting = models.ElementAt(index);
        }

        return modelSetting;
    }


    public List<LlmProviderSetting> GetLlmConfigs(LlmConfigOptions? options = null)
    {
        var settingService = _services.GetRequiredService<ISettingService>();
        var providers = settingService.Bind<List<LlmProviderSetting>>($"LlmProviders");
        var configs = new List<LlmProviderSetting>();

        if (providers.IsNullOrEmpty()) return configs;

        if (options == null) return providers ?? [];

        foreach (var provider in providers)
        {
            var models = provider.Models ?? [];
            if (options.Type.HasValue)
            {
                models = models.Where(x => x.Type == options.Type.Value).ToList();
            }

            if (options.MultiModal.HasValue)
            {
                models = models.Where(x => x.MultiModal == options.MultiModal.Value).ToList();
            }

            if (options.ImageGeneration.HasValue)
            {
                models = models.Where(x => x.ImageGeneration == options.ImageGeneration.Value).ToList();
            }

            if (options.RealTime.HasValue)
            {
                models = models.Where(x => x.RealTime == options.RealTime.Value).ToList();
            }

            if (models.IsNullOrEmpty())
            {
                continue;
            }

            provider.Models = models;
            configs.Add(provider);
        }

        return configs;
    }
}