using AIStudio.Components;
using AIStudio.Provider;
using AIStudio.Settings;
using AIStudio.Tools.Services;
using AIStudio.Tools.Validation;

using Microsoft.AspNetCore.Components;

using Host = AIStudio.Provider.SelfHosted.Host;

namespace AIStudio.Dialogs;

public partial class EmbeddingProviderDialog : MSGComponentBase, ISecretId
{
    [CascadingParameter]
    private IMudDialogInstance MudDialog { get; set; } = null!;

    /// <summary>
    /// The embedding's number in the list.
    /// </summary>
    [Parameter]
    public uint DataNum { get; set; }
    
    /// <summary>
    /// The embedding's ID.
    /// </summary>
    [Parameter]
    public string DataId { get; set; } = Guid.NewGuid().ToString();
    
    /// <summary>
    /// The user chosen name.
    /// </summary>
    [Parameter]
    public string DataName { get; set; } = string.Empty;
    
    /// <summary>
    /// The chosen hostname for self-hosted providers.
    /// </summary>
    [Parameter]
    public string DataHostname { get; set; } = string.Empty;
    
    /// <summary>
    /// The host to use, e.g., llama.cpp.
    /// </summary>
    [Parameter]
    public Host DataHost { get; set; } = Host.NONE;
    
    /// <summary>
    /// Is this provider self-hosted?
    /// </summary>
    [Parameter]
    public bool IsSelfHosted { get; set; }
    
    /// <summary>
    /// The provider to use.
    /// </summary>
    [Parameter]
    public LLMProviders DataLLMProvider { get; set; } = LLMProviders.NONE;
    
    /// <summary>
    /// The embedding model to use.
    /// </summary>
    [Parameter]
    public Model DataModel { get; set; }
    
    /// <summary>
    /// Should the dialog be in editing mode?
    /// </summary>
    [Parameter]
    public bool IsEditing { get; init; }
    
    [Inject]
    private RustService RustService { get; init; } = null!;

    [Inject]
    private ILogger<EmbeddingProviderDialog> Logger { get; init; } = null!;

    private static readonly Dictionary<string, object?> SPELLCHECK_ATTRIBUTES = new();

    /// <summary>
    /// The list of used instance names. We need this to check for uniqueness.
    /// </summary>
    private List<string> UsedInstanceNames { get; set; } = [];
    
    private bool dataIsValid;
    private string[] dataIssues = [];
    private string dataAPIKey = string.Empty;
    private string dataManuallyModel = string.Empty;
    private string dataAPIKeyStorageIssue = string.Empty;
    private string dataEditingPreviousInstanceName = string.Empty;
    private string dataLoadingModelsIssue = string.Empty;

    // We get the form reference from Blazor code to validate it manually:
    private MudForm form = null!;
    
    private readonly List<Model> availableModels = new();
    private readonly Encryption encryption = Program.ENCRYPTION;
    private readonly ProviderValidation providerValidation;
    
    public EmbeddingProviderDialog()
    {
        this.providerValidation = new()
        {
            GetProvider = () => this.DataLLMProvider,
            GetAPIKeyStorageIssue = () => this.dataAPIKeyStorageIssue,
            GetPreviousInstanceName = () => this.dataEditingPreviousInstanceName,
            GetUsedInstanceNames = () => this.UsedInstanceNames,
            GetHost = () => this.DataHost,
            IsModelProvidedManually = () => this.DataLLMProvider is LLMProviders.SELF_HOSTED && this.DataHost is Host.OLLAMA,
        };
    }
    
    private EmbeddingProvider CreateEmbeddingProviderSettings()
    {
        var cleanedHostname = this.DataHostname.Trim();
        Model model = default;
        if(this.DataLLMProvider is LLMProviders.SELF_HOSTED)
        {
            if (this.DataHost is Host.OLLAMA)
                model = new Model(this.dataManuallyModel, null);
            else if (this.DataHost is Host.LM_STUDIO)
                model = this.DataModel;
        }
        else
            model = this.DataModel;
        
        return new()
        {
            Num = this.DataNum,
            Id = this.DataId,
            Name = this.DataName,
            UsedLLMProvider = this.DataLLMProvider,
            Model = model,
            IsSelfHosted = this.DataLLMProvider is LLMProviders.SELF_HOSTED,
            Hostname = cleanedHostname.EndsWith('/') ? cleanedHostname[..^1] : cleanedHostname,
            Host = this.DataHost,
            IsEnterpriseConfiguration = false,
            EnterpriseConfigurationPluginId = Guid.Empty,
        };
    }
    
    #region Overrides of ComponentBase

    protected override async Task OnInitializedAsync()
    {
        // Call the base initialization first so that the I18N is ready:
        await base.OnInitializedAsync();
        
        // Configure the spellchecking for the instance name input:
        this.SettingsManager.InjectSpellchecking(SPELLCHECK_ATTRIBUTES);
        
        // Load the used instance names:
        this.UsedInstanceNames = this.SettingsManager.ConfigurationData.EmbeddingProviders.Select(x => x.Name.ToLowerInvariant()).ToList();
        
        // When editing, we need to load the data:
        if(this.IsEditing)
        {
            this.dataEditingPreviousInstanceName = this.DataName.ToLowerInvariant();
            
            // When using self-hosted embedding, we must copy the model name:
            if (this.DataLLMProvider is LLMProviders.SELF_HOSTED)
                this.dataManuallyModel = this.DataModel.Id;
            
            //
            // We cannot load the API key for self-hosted providers:
            //
            if (this.DataLLMProvider is LLMProviders.SELF_HOSTED && this.DataHost is not Host.OLLAMA)
            {
                await this.ReloadModels();
                await base.OnInitializedAsync();
                return;
            }
            
            // Load the API key:
            var requestedSecret = await this.RustService.GetAPIKey(this, SecretStoreType.EMBEDDING_PROVIDER, isTrying: this.DataLLMProvider is LLMProviders.SELF_HOSTED);
            if (requestedSecret.Success)
                this.dataAPIKey = await requestedSecret.Secret.Decrypt(this.encryption);
            else
            {
                this.dataAPIKey = string.Empty;
                if (this.DataLLMProvider is not LLMProviders.SELF_HOSTED)
                {
                    this.dataAPIKeyStorageIssue = string.Format(T("Failed to load the API key from the operating system. The message was: {0}. You might ignore this message and provide the API key again."), requestedSecret.Issue);
                    await this.form.Validate();
                }
            }

            await this.ReloadModels();
        }
    }

    protected override async Task OnAfterRenderAsync(bool firstRender)
    {
        // Reset the validation when not editing and on the first render.
        // We don't want to show validation errors when the user opens the dialog.
        if(!this.IsEditing && firstRender)
            this.form.ResetValidation();
        
        await base.OnAfterRenderAsync(firstRender);
    }

    #endregion
    
    #region Implementation of ISecretId

    public string SecretId => this.DataLLMProvider.ToSecretId();
    
    public string SecretName => this.DataName;

    #endregion
    
    private async Task Store()
    {
        await this.form.Validate();
        this.dataAPIKeyStorageIssue = string.Empty;

        // Manually validate the model selection (needed when no models are loaded
        // and the MudSelect is not rendered):
        var modelValidationError = this.providerValidation.ValidatingModel(this.DataModel);
        if (!string.IsNullOrWhiteSpace(modelValidationError))
        {
            this.dataIssues = [..this.dataIssues, modelValidationError];
            this.dataIsValid = false;
        }

        // When the data is not valid, we don't store it:
        if (!this.dataIsValid)
            return;
        
        // Use the data model to store the provider.
        // We just return this data to the parent component:
        var addedProviderSettings = this.CreateEmbeddingProviderSettings();
        if (!string.IsNullOrWhiteSpace(this.dataAPIKey))
        {
            // Store the API key in the OS secure storage:
            var storeResponse = await this.RustService.SetAPIKey(this, this.dataAPIKey, SecretStoreType.EMBEDDING_PROVIDER);
            if (!storeResponse.Success)
            {
                this.dataAPIKeyStorageIssue = string.Format(T("Failed to store the API key in the operating system. The message was: {0}. Please try again."), storeResponse.Issue);
                await this.form.Validate();
                return;
            }
        }

        this.MudDialog.Close(DialogResult.Ok(addedProviderSettings));
    }
    
    private string? ValidateManuallyModel(string manuallyModel)
    {
        if (this.DataLLMProvider is LLMProviders.SELF_HOSTED && string.IsNullOrWhiteSpace(manuallyModel))
            return T("Please enter an embedding model name.");
        
        return null;
    }

    private void Cancel() => this.MudDialog.Cancel();

    private async Task OnAPIKeyChanged(string apiKey)
    {
        this.dataAPIKey = apiKey;
        if (!string.IsNullOrWhiteSpace(this.dataAPIKeyStorageIssue))
        {
            this.dataAPIKeyStorageIssue = string.Empty;
            await this.form.Validate();
        }
    }

    private void OnHostChanged(Host selectedHost)
    {
        // When the host changes, reset the model selection state:
        this.DataHost = selectedHost;
        this.DataModel = default;
        this.dataManuallyModel = string.Empty;
        this.availableModels.Clear();
        this.dataLoadingModelsIssue = string.Empty;
    }

    private async Task ReloadModels()
    {
        this.dataLoadingModelsIssue = string.Empty;
        var currentEmbeddingProviderSettings = this.CreateEmbeddingProviderSettings();
        var provider = currentEmbeddingProviderSettings.CreateProvider();
        if (provider is NoProvider)
            return;

        try
        {
            var result = await provider.GetEmbeddingModels(this.dataAPIKey);
            if (!result.Success)
                this.dataLoadingModelsIssue = result.FailureReason.ToUserMessage(provider.InstanceName);

            // Order descending by ID means that the newest models probably come first:
            var orderedModels = result.Models.OrderByDescending(n => n.Id);

            this.availableModels.Clear();
            this.availableModels.AddRange(orderedModels);
        }
        catch (Exception e)
        {
            this.Logger.LogError($"Failed to load models from provider '{this.DataLLMProvider}' (host={this.DataHost}, hostname='{this.DataHostname}'): {e.Message}");
            this.dataLoadingModelsIssue = T("We are currently unable to communicate with the provider to load models. Please try again later.");
        }
    }
    
    private string APIKeyText => this.DataLLMProvider switch
    {
        LLMProviders.SELF_HOSTED => T("(Optional) API Key"),
        _ => T("API Key"),
    };
    
    private bool IsNoneProvider => this.DataLLMProvider is LLMProviders.NONE;
}