BotSharp/src/Infrastructure/BotSharp.Core/Files/Functions/ReadFileFn.cs

using BotSharp.Abstraction.Functions;
using BotSharp.Abstraction.MLTasks;

namespace BotSharp.Core.Files.Functions;

public class ReadFileFn : IFunctionCallback
{
    public string Name => "read_file";
    public string Indication => "Reading files";

    private readonly IServiceProvider _services;
    private readonly ILogger<ReadFileFn> _logger;
    private readonly IEnumerable<string> _imageTypes = new List<string> { "image", "images", "png", "jpg", "jpeg" };
    private readonly IEnumerable<string> _pdfTypes = new List<string> { "pdf" };
    private static string UTILITY_ASSISTANT = Guid.Empty.ToString();

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

    public async Task<bool> Execute(RoleDialogModel message)
    {
        var args = JsonSerializer.Deserialize<LlmFileContext>(message.FunctionArgs);
        var conv = _services.GetRequiredService<IConversationService>();
        var agentService = _services.GetRequiredService<IAgentService>();
        
        var wholeDialogs = conv.GetDialogHistory();
        var fileTypes = args?.FileTypes?.Split(",", StringSplitOptions.RemoveEmptyEntries)?.ToList() ?? new List<string>();
        var dialogs = await AssembleFiles(conv.ConversationId, wholeDialogs, fileTypes);
        var agent = await agentService.LoadAgent(UTILITY_ASSISTANT);
        var fileAgent = new Agent
        {
            Id = agent?.Id ?? Guid.Empty.ToString(),
            Name = agent?.Name ?? "Unkown",
            Instruction = !string.IsNullOrWhiteSpace(args?.UserRequest) ? args.UserRequest : "Please describe the files.",
            TemplateDict = new Dictionary<string, object>()
        };

        var response = await GetChatCompletion(fileAgent, dialogs);
        message.Content = response;
        message.StopCompletion = true;
        return true;
    }

    private async Task<List<RoleDialogModel>> AssembleFiles(string conversationId, List<RoleDialogModel> dialogs, List<string> fileTypes)
    {
        if (dialogs.IsNullOrEmpty())
        {
            return new List<RoleDialogModel>();
        }

        var parsedTypes = ParseFileTypes(fileTypes);
        var fileService = _services.GetRequiredService<IBotSharpFileService>();
        var files = await fileService.GetChatImages(conversationId, FileSourceType.User, parsedTypes, dialogs);

        foreach (var dialog in dialogs)
        {
            var found = files.Where(x => x.MessageId == dialog.MessageId).ToList();
            if (found.IsNullOrEmpty()) continue;

            dialog.Files = found.Select(x => new BotSharpFile
            {
                ContentType = x.ContentType,
                FileStorageUrl = x.FileStorageUrl
            }).ToList();
        }

        return dialogs;
    }

    private IEnumerable<string> ParseFileTypes(IEnumerable<string> fileTypes)
    {
        var imageType = "image";
        var pdfType = "pdf";
        var parsed = new List<string>();

        if (fileTypes.IsNullOrEmpty())
        {
            return new List<string> { imageType };
        }

        foreach (var fileType in fileTypes)
        {
            var type = fileType?.Trim();
            if (string.IsNullOrWhiteSpace(type) || _imageTypes.Any(x => type.IsEqualTo(x)))
            {
                parsed.Add(imageType);
            }
            else if (_pdfTypes.Any(x => type.IsEqualTo(x)))
            {
                parsed.Add(pdfType);
            }
        }

        if (parsed.IsNullOrEmpty())
        {
            parsed.Add(imageType);
        }

        return parsed.Distinct();
    }

    private async Task<string> GetChatCompletion(Agent agent, List<RoleDialogModel> dialogs)
    {
        try
        {
            var llmProviderService = _services.GetRequiredService<ILlmProviderService>();
            var provider = llmProviderService.GetProviders().FirstOrDefault(x => x == "openai");
            var model = llmProviderService.GetProviderModel(provider: provider, id: "gpt-4", multiModal: true);
            var completion = CompletionProvider.GetChatCompletion(_services, provider: provider, model: model.Name);
            var response = await completion.GetChatCompletions(agent, dialogs);
            return response.Content;
        }
        catch (Exception ex)
        {
            var error = $"Error when analyzing files.";
            _logger.LogWarning($"{error} {ex.Message}");
            return error;
        }
    }
}