@page "/database-schema"
@using DataConnection.Interfaces
@using DataConnection.Enums
@inject Data.DatabaseConnectionService DatabaseService
@inject IJSRuntime JSRuntime
@inject NavigationManager NavigationManager

<PageTitle>Schema del Database</PageTitle>

<h3>Schema del Database</h3>

@if (!DatabaseService.IsConnected || string.IsNullOrEmpty(DatabaseService.SelectedDatabase))
{
    <div class="alert alert-warning">
        <p>Non sei connesso a nessun database. Devi prima stabilire una connessione.</p>
        <button class="btn btn-primary" @onclick="NavigateToConnection">Vai alla pagina di connessione</button>
    </div>
}
else
{
    <div class="row mb-4">
        <div class="col-md-12">
            <div class="card">
                <div class="card-header d-flex justify-content-between align-items-center">
                    <span>Dettagli del Database: <strong>@DatabaseService.SelectedDatabase</strong></span>
                    <button class="btn btn-outline-primary btn-sm" @onclick="RefreshSchema">
                        <i class="oi oi-reload"></i> Aggiorna Schema
                    </button>
                </div>
                <div class="card-body">
                    @if (databaseInfo != null)
                    {
                        <div class="row">
                            <div class="col-md-3">
                                <strong>Nome:</strong> @databaseInfo.Name
                            </div>
                            <div class="col-md-3">
                                <strong>Dimensione:</strong> @databaseInfo.SizeMB.ToString("N2") MB
                            </div>
                            <div class="col-md-3">
                                <strong>Creato il:</strong> @databaseInfo.CreationDate.ToString("dd/MM/yyyy HH:mm")
                            </div>
                            <div class="col-md-3">
                                <strong>Stato:</strong> @databaseInfo.Status
                            </div>
                        </div>
                    }
                </div>
            </div>
        </div>
    </div>

    <div class="row">
        <div class="col-md-3">
            <div class="card">
                <div class="card-header">
                    Tabelle
                </div>
                <div class="card-body p-0">
                    <div class="list-group list-group-flush">
                        <input type="text" class="form-control border-0 mb-2" placeholder="Filtra tabelle..." @oninput="FilterTables" />
                        
                        @if (schemaInfo != null && schemaInfo.Count > 0)
                        {
                            @foreach (var table in filteredTables)
                            {
                                <button class="list-group-item list-group-item-action @(selectedTable == table.Key ? "active" : "")"
                                        @onclick="() => SelectTable(table.Key)">
                                    @table.Key
                                </button>
                            }
                        }
                        else if (isLoading)
                        {
                            <div class="text-center p-3">
                                <div class="spinner-border" role="status">
                                    <span class="visually-hidden">Caricamento...</span>
                                </div>
                            </div>
                        }
                        else
                        {
                            <div class="list-group-item text-center text-muted">
                                Nessuna tabella disponibile
                            </div>
                        }
                    </div>
                </div>
            </div>
        </div>
        
        <div class="col-md-9">
            <div class="card">
                <div class="card-header">
                    @if (!string.IsNullOrEmpty(selectedTable))
                    {
                        <span>Struttura della tabella: <strong>@selectedTable</strong></span>
                    }
                    else
                    {
                        <span>Seleziona una tabella</span>
                    }
                </div>
                <div class="card-body">
                    @if (!string.IsNullOrEmpty(selectedTable) && schemaInfo != null && schemaInfo.ContainsKey(selectedTable))
                    {
                        <div class="table-responsive">
                            <table class="table table-bordered table-hover">
                                <thead class="table-light">
                                    <tr>
                                        <th>Nome Colonna</th>
                                        <th>Tipo Dati</th>
                                        <th>Nullable</th>
                                        <th>Chiave</th>
                                        <th>Relazioni</th>
                                    </tr>
                                </thead>
                                <tbody>
                                    @foreach (var column in schemaInfo[selectedTable])
                                    {
                                        <tr>
                                            <td>@column.Name</td>
                                            <td>@column.DataType</td>
                                            <td>
                                                @if (column.IsNullable)
                                                {
                                                    <span class="badge bg-secondary">NULL</span>
                                                }
                                                else
                                                {
                                                    <span class="badge bg-danger">NOT NULL</span>
                                                }
                                            </td>
                                            <td>
                                                @if (column.IsPrimaryKey)
                                                {
                                                    <span class="badge bg-primary">PK</span>
                                                }
                                            </td>
                                            <td>
                                                @if (column.IsForeignKey)
                                                {
                                                    <span class="badge bg-info text-dark">
                                                        FK → @column.ReferencedTable.@column.ReferencedColumn
                                                    </span>
                                                }
                                            </td>
                                        </tr>
                                    }
                                </tbody>
                            </table>
                        </div>
                    }
                    else if (string.IsNullOrEmpty(selectedTable))
                    {
                        <div class="alert alert-info">
                            Seleziona una tabella dal menu a sinistra per visualizzarne la struttura.
                        </div>
                    }
                    else if (isLoading)
                    {
                        <div class="text-center">
                            <div class="spinner-border" role="status">
                                <span class="visually-hidden">Caricamento...</span>
                            </div>
                        </div>
                    }
                    else
                    {
                        <div class="alert alert-warning">
                            Impossibile trovare informazioni sulla tabella selezionata.
                        </div>
                    }
                </div>
            </div>
        </div>
    </div>
}

@code {
    private bool isLoading = false;
    private string selectedTable = "";
    private string tableFilter = "";
    private DatabaseInfo databaseInfo;
    private IDictionary<string, IEnumerable<DbColumnInfo>> schemaInfo;
    private IDictionary<string, IEnumerable<DbColumnInfo>> filteredTables;

    protected override async Task OnInitializedAsync()
    {
        if (DatabaseService.IsConnected && !string.IsNullOrEmpty(DatabaseService.SelectedDatabase))
        {
            await LoadDatabaseSchema();
        }
    }

    private async Task LoadDatabaseSchema()
    {
        try
        {
            isLoading = true;
            selectedTable = "";

            // Ottieni informazioni sul database selezionato
            if (DatabaseService.DatabasesInfo.TryGetValue(DatabaseService.SelectedDatabase, out var dbInfo))
            {
                databaseInfo = dbInfo;
            }
            
            // Crea il database manager e connettiti al database selezionato
            var databaseManager = DatabaseService.GetDatabaseManager();
            
            // Verifica la connessione al database specifico
            if (await databaseManager.TestConnectionAsync())
            {
                // Recupera le informazioni sullo schema (tabelle e colonne)
                schemaInfo = await databaseManager.GetDatabaseSchemaAsync();
                filteredTables = schemaInfo;
            }
            else
            {
                throw new Exception($"Non è possibile connettersi al database {DatabaseService.SelectedDatabase}");
            }
        }
        catch (Exception ex)
        {
            await JSRuntime.InvokeVoidAsync("console.error", "Errore caricamento schema:", ex.Message);
            //DatabaseService.ErrorMessage = $"Errore nel caricamento dello schema: {ex.Message}";
            schemaInfo = null;
        }
        finally
        {
            isLoading = false;
        }
    }

    private void SelectTable(string tableName)
    {
        selectedTable = tableName;
    }

    private void FilterTables(ChangeEventArgs e)
    {
        tableFilter = e.Value?.ToString() ?? "";
        
        if (string.IsNullOrWhiteSpace(tableFilter))
        {
            filteredTables = schemaInfo;
        }
        else
        {
            filteredTables = schemaInfo
                .Where(t => t.Key.Contains(tableFilter, StringComparison.OrdinalIgnoreCase))
                .ToDictionary(t => t.Key, t => t.Value);
        }
    }

    private async Task RefreshSchema()
    {
        await LoadDatabaseSchema();
    }

    private void NavigateToConnection()
    {
        NavigationManager.NavigateTo("/database-connection");
    }
}