Part VI: Admin DSL -- Auto-Generated UI📋

namespace Cmf.Admin.Lib;

/// <summary>
/// Declares an admin module for a given aggregate root. The source
/// generator produces a complete Blazor CRUD interface: list page,
/// form page, detail page, and navigation entry.
/// </summary>
[MetaConcept("AdminModule")]
[MetaReference("Aggregate", "AggregateRoot", Multiplicity = "1")]
[MetaConstraint("AggregateMustExist",
    "ReferencedType.IsAnnotatedWith('AggregateRoot')",
    Message = "AdminModule must reference an [AggregateRoot] type")]
public sealed class AdminModuleAttribute : Attribute
{
    [MetaProperty("Name", "string", Required = true)]
    public string Name { get; }

    [MetaProperty("Aggregate", "Type", Required = true)]
    public Type Aggregate { get; }

    [MetaProperty("Icon", "string")]
    public string? Icon { get; set; }

    [MetaProperty("Group", "string")]
    public string? Group { get; set; }

    [MetaProperty("PageSize", "int")]
    public int PageSize { get; set; } = 25;

    public AdminModuleAttribute(string name, Type aggregate)
    {
        Name = name;
        Aggregate = aggregate;
    }
}

/// <summary>
/// Overrides the default rendering for a specific field in the admin
/// form and list view. Without this attribute, the generator infers
/// display types from property types (string → text input, bool → checkbox,
/// decimal → number input, enum → dropdown).
/// </summary>
[MetaConcept("AdminField")]
[AttributeUsage(AttributeTargets.Property, AllowMultiple = false)]
public sealed class AdminFieldAttribute : Attribute
{
    [MetaProperty("Name", "string", Required = true)]
    public string Name { get; }

    [MetaProperty("DisplayType", "string")]
    public string? DisplayType { get; set; }

    [MetaProperty("DisplayName", "string")]
    public string? DisplayName { get; set; }

    [MetaProperty("ReadOnly", "bool")]
    public bool ReadOnly { get; set; } = false;

    [MetaProperty("HideInList", "bool")]
    public bool HideInList { get; set; } = false;

    [MetaProperty("HideInForm", "bool")]
    public bool HideInForm { get; set; } = false;

    [MetaProperty("Order", "int")]
    public int Order { get; set; } = 0;

    public AdminFieldAttribute(string name) => Name = name;
}

/// <summary>
/// Adds a filter control to the list view for the admin module.
/// Filters appear above the list table and apply server-side
/// query filtering via the generated repository.
/// </summary>
[MetaConcept("AdminFilter")]
[AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
public sealed class AdminFilterAttribute : Attribute
{
    [MetaProperty("FieldName", "string", Required = true)]
    public string FieldName { get; }

    [MetaProperty("FilterType", "string")]
    public string FilterType { get; set; } = "Text";

    [MetaProperty("DisplayName", "string")]
    public string? DisplayName { get; set; }

    [MetaProperty("Options", "string[]")]
    public string[]? Options { get; set; }

    public AdminFilterAttribute(string fieldName) => FieldName = fieldName;
}

/// <summary>
/// Declares a custom bulk action available on the list view.
/// When the user selects rows and invokes the action, the framework
/// dispatches the specified command for each selected entity.
/// </summary>
[MetaConcept("AdminAction")]
[MetaReference("Command", "Command", Multiplicity = "0..1")]
[AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
public sealed class AdminActionAttribute : Attribute
{
    [MetaProperty("Name", "string", Required = true)]
    public string Name { get; }

    [MetaProperty("Command", "string", Required = true)]
    public string Command { get; set; }

    [MetaProperty("Icon", "string")]
    public string? Icon { get; set; }

    [MetaProperty("ConfirmationMessage", "string")]
    public string? ConfirmationMessage { get; set; }

    [MetaProperty("RequiresRole", "string")]
    public string? RequiresRole { get; set; }

    public AdminActionAttribute(string name) => Name = name;
}

namespace MyStore.Lib.Catalog;

[AggregateRoot("Product", BoundedContext = "Catalog")]
[HasPart(typeof(RoutablePart))]
[HasPart(typeof(SeoablePart))]
[HasPart(typeof(VersionablePart))]
public partial class Product
{
    [EntityId]
    public partial ProductId Id { get; }

    [Property("Name", Required = true, MaxLength = 200)]
    [AdminField("Name", Order = 1)]
    public partial string Name { get; }

    [Property("Sku", Required = true, MaxLength = 50)]
    [AdminField("SKU", Order = 2)]
    public partial string Sku { get; }

    [Property("Description", MaxLength = 2000)]
    [AdminField("Description", DisplayType = "TextArea", HideInList = true, Order = 3)]
    public partial string? Description { get; }

    [Property("Price", Required = true)]
    [AdminField("Price", DisplayType = "Currency", Order = 4)]
    public partial decimal Price { get; }

    [Property("Category", Required = true)]
    [AdminField("Category", DisplayType = "Dropdown", Order = 5)]
    public partial ProductCategory Category { get; }

    [Property("IsActive")]
    [AdminField("Active", Order = 6)]
    public partial bool IsActive { get; }

    [Property("StockQuantity", Required = true)]
    [AdminField("Stock", Order = 7)]
    public partial int StockQuantity { get; }

    [StreamField("Gallery", AllowedBlockTypes = new[] { typeof(ImageBlock) })]
    [AdminField("Gallery", DisplayType = "StreamField", HideInList = true, Order = 8)]
    public partial IReadOnlyList<IContentBlock> Gallery { get; }

    [Invariant("Product must have a positive price")]
    private Result PriceIsPositive()
        => Price > 0
            ? Result.Success()
            : Result.Failure("Product price must be positive");

    [Invariant("Product must have non-negative stock")]
    private Result StockIsNonNegative()
        => StockQuantity >= 0
            ? Result.Success()
            : Result.Failure("Stock quantity cannot be negative");
}

public enum ProductCategory { Electronics, Clothing, Books, Home, Sports }

namespace MyStore.Admin;

/// <summary>
/// Declares the Product admin module. The generator produces
/// list, form, and detail pages for the Product aggregate.
/// </summary>
[AdminModule("Products", typeof(Product), Icon = "box", Group = "Catalog")]
[AdminFilter("Category", FilterType = "Dropdown", DisplayName = "Category")]
[AdminFilter("IsActive", FilterType = "Boolean", DisplayName = "Active Status")]
[AdminFilter("Price", FilterType = "NumberRange", DisplayName = "Price Range")]
[AdminAction("Publish", Command = "PublishProduct",
    Icon = "send", ConfirmationMessage = "Publish selected products?",
    RequiresRole = "Editor")]
[AdminAction("Deactivate", Command = "DeactivateProduct",
    Icon = "x-circle", ConfirmationMessage = "Deactivate selected products?",
    RequiresRole = "Admin")]
public partial class ProductAdminModule { }

// Generated: ProductListPage.razor
@page "/admin/products"
@namespace MyStore.Admin.Pages
@attribute [Authorize(Roles = "Editor,Admin")]
@inject IProductRepository Repository
@inject NavigationManager Navigation

<PageTitle>Products</PageTitle>

<div class="admin-list-page">
    <header class="admin-header">
        <h1>Products</h1>
        <button class="btn btn-primary" @onclick="NavigateToCreate">
            + New Product
        </button>
    </header>

    @* ── Filters ── *@
    <div class="admin-filters">
        <AdminDropdownFilter Label="Category" @bind-Value="Filters.Category"
            Options="@ProductCategoryOptions" />
        <AdminBooleanFilter Label="Active Status" @bind-Value="Filters.IsActive" />
        <AdminNumberRangeFilter Label="Price Range"
            @bind-Min="Filters.PriceMin" @bind-Max="Filters.PriceMax" />
        <button class="btn btn-secondary" @onclick="ApplyFilters">Apply</button>
        <button class="btn btn-link" @onclick="ClearFilters">Clear</button>
    </div>

    @* ── Batch Actions ── *@
    @if (SelectedIds.Count > 0)
    {
        <div class="admin-batch-actions">
            <span>@SelectedIds.Count selected</span>
            <AdminBatchAction Label="Publish" Icon="send"
                OnClick="BatchPublish"
                Confirmation="Publish selected products?" />
            <AdminBatchAction Label="Deactivate" Icon="x-circle"
                OnClick="BatchDeactivate"
                Confirmation="Deactivate selected products?" />
        </div>
    }

    @* ── Data Table ── *@
    <AdminDataTable TItem="Product" Items="Products" @bind-SelectedIds="SelectedIds"
        OnSort="HandleSort" CurrentSort="SortColumn" SortDescending="SortDesc">
        <AdminColumn Title="Name" Field="Name" Sortable="true" />
        <AdminColumn Title="SKU" Field="Sku" Sortable="true" />
        <AdminColumn Title="Price" Field="Price" Sortable="true"
            Format="Currency" />
        <AdminColumn Title="Category" Field="Category" Sortable="true" />
        <AdminColumn Title="Active" Field="IsActive" Sortable="true"
            DisplayType="Badge" />
        <AdminColumn Title="Stock" Field="StockQuantity" Sortable="true" />
        <AdminActionsColumn>
            <button @onclick="() => NavigateToEdit(context.Id)">Edit</button>
            <button @onclick="() => NavigateToDetail(context.Id)">View</button>
        </AdminActionsColumn>
    </AdminDataTable>

    @* ── Pagination ── *@
    <AdminPagination TotalItems="TotalCount" PageSize="25"
        @bind-CurrentPage="CurrentPage" OnPageChanged="LoadPage" />
</div>

@code {
    private List<Product> Products { get; set; } = new();
    private HashSet<ProductId> SelectedIds { get; set; } = new();
    private ProductListFilters Filters { get; set; } = new();
    private int TotalCount { get; set; }
    private int CurrentPage { get; set; } = 1;
    private string SortColumn { get; set; } = "Name";
    private bool SortDesc { get; set; } = false;

    protected override async Task OnInitializedAsync()
        => await LoadPage(1);

    private async Task LoadPage(int page)
    {
        var result = await Repository.GetPagedAsync(
            page, pageSize: 25, Filters, SortColumn, SortDesc);
        Products = result.Items.ToList();
        TotalCount = result.TotalCount;
        CurrentPage = page;
    }

    // Navigation, sorting, batch action handlers...
}

// Generated: ProductFormPage.razor
@page "/admin/products/new"
@page "/admin/products/{Id:guid}/edit"
@namespace MyStore.Admin.Pages
@attribute [Authorize(Roles = "Editor,Admin")]
@inject IProductRepository Repository
@inject ICommandDispatcher Commands
@inject NavigationManager Navigation

<PageTitle>@(IsEdit ? "Edit Product" : "New Product")</PageTitle>

<div class="admin-form-page">
    <header class="admin-header">
        <h1>@(IsEdit ? $"Edit: {Model.Name}" : "New Product")</h1>
    </header>

    <EditForm Model="Model" OnValidSubmit="HandleSubmit">
        <DataAnnotationsValidator />
        <ValidationSummary />

        @* ── Core Fields ── *@
        <fieldset>
            <legend>Product Information</legend>
            <AdminTextField Label="Name" @bind-Value="Model.Name"
                Required="true" MaxLength="200" />
            <AdminTextField Label="SKU" @bind-Value="Model.Sku"
                Required="true" MaxLength="50" />
            <AdminTextArea Label="Description" @bind-Value="Model.Description"
                MaxLength="2000" />
            <AdminCurrencyField Label="Price" @bind-Value="Model.Price" />
            <AdminDropdownField Label="Category" @bind-Value="Model.Category"
                Options="@ProductCategoryOptions" />
            <AdminCheckboxField Label="Active" @bind-Value="Model.IsActive" />
            <AdminNumberField Label="Stock" @bind-Value="Model.StockQuantity" />
        </fieldset>

        @* ── Content Part Fields (auto-injected from [HasPart]) ── *@
        <fieldset>
            <legend>URL & Routing</legend>
            <AdminSlugField Label="Slug" @bind-Value="Model.RoutablePart.Slug"
                SourceField="Model.Name" />
        </fieldset>

        <fieldset>
            <legend>SEO</legend>
            <AdminTextField Label="Meta Title" @bind-Value="Model.SeoablePart.MetaTitle"
                MaxLength="70" HelpText="Browser tab title" />
            <AdminTextArea Label="Meta Description"
                @bind-Value="Model.SeoablePart.MetaDescription"
                MaxLength="160" HelpText="Search result snippet" />
            <AdminTextField Label="OG Image" @bind-Value="Model.SeoablePart.OgImage"
                HelpText="Social sharing image URL" />
        </fieldset>

        <fieldset>
            <legend>Publishing</legend>
            <AdminReadOnlyField Label="Version"
                Value="@Model.VersionablePart.VersionNumber.ToString()" />
            <AdminReadOnlyField Label="Status"
                Value="@Model.VersionablePart.Status.ToString()" />
        </fieldset>

        @* ── StreamField: Gallery ── *@
        <fieldset>
            <legend>Gallery</legend>
            <StreamFieldEditor @bind-Value="Model.Gallery"
                AllowedBlockTypes="@(new[] { typeof(ImageBlock) })" />
        </fieldset>

        <div class="admin-form-actions">
            <button type="submit" class="btn btn-primary">
                @(IsEdit ? "Save Changes" : "Create Product")
            </button>
            <button type="button" class="btn btn-secondary"
                @onclick="Cancel">Cancel</button>
        </div>
    </EditForm>
</div>

@code {
    [Parameter] public Guid? Id { get; set; }
    private ProductFormModel Model { get; set; } = new();
    private bool IsEdit => Id.HasValue;

    protected override async Task OnParametersSetAsync()
    {
        if (IsEdit)
        {
            var product = await Repository.GetByIdAsync(
                new ProductId(Id!.Value));
            if (product is not null)
                Model = ProductFormModel.FromEntity(product);
        }
    }

    private async Task HandleSubmit()
    {
        if (IsEdit)
            await Commands.DispatchAsync(Model.ToUpdateCommand());
        else
            await Commands.DispatchAsync(Model.ToCreateCommand());

        Navigation.NavigateTo("/admin/products");
    }
}

// Generated: ProductDetailPage.razor
@page "/admin/products/{Id:guid}"
@namespace MyStore.Admin.Pages
@attribute [Authorize(Roles = "Editor,Admin")]
@inject IProductRepository Repository

<PageTitle>Product: @Product?.Name</PageTitle>

<div class="admin-detail-page">
    @if (Product is not null)
    {
        <header class="admin-header">
            <h1>@Product.Name</h1>
            <div class="admin-header-actions">
                <a href="/admin/products/@Id/edit" class="btn btn-primary">Edit</a>
            </div>
        </header>

        <div class="admin-detail-grid">
            <AdminDetailField Label="SKU" Value="@Product.Sku" />
            <AdminDetailField Label="Price" Value="@Product.Price.ToString("C")" />
            <AdminDetailField Label="Category" Value="@Product.Category.ToString()" />
            <AdminDetailField Label="Active" Value="@Product.IsActive.ToString()" />
            <AdminDetailField Label="Stock" Value="@Product.StockQuantity.ToString()" />
            <AdminDetailField Label="Slug" Value="@Product.RoutablePart.Slug" />
            <AdminDetailField Label="URL" Value="@Product.RoutablePart.UrlPath" />
            <AdminDetailField Label="Version"
                Value="@Product.VersionablePart.VersionNumber.ToString()" />
            <AdminDetailField Label="Status"
                Value="@Product.VersionablePart.Status.ToString()" />
        </div>

        @if (!string.IsNullOrEmpty(Product.Description))
        {
            <section class="admin-detail-section">
                <h2>Description</h2>
                <p>@Product.Description</p>
            </section>
        }
    }
</div>

@code {
    [Parameter] public Guid Id { get; set; }
    private Product? Product { get; set; }

    protected override async Task OnParametersSetAsync()
        => Product = await Repository.GetByIdAsync(new ProductId(Id));
}

// Order aggregate with OrderLine composition (from Part IV)
[AggregateRoot("Order", BoundedContext = "Ordering")]
public partial class Order
{
    [Composition]
    public partial IReadOnlyList<OrderLine> Lines { get; }
}

[AdminModule("Orders", typeof(Order), Icon = "shopping-cart", Group = "Sales")]
public partial class OrderAdminModule { }

// Generated: OrderFormPage.razor (excerpt)
<fieldset>
    <legend>Order Lines</legend>
    <AdminInlineTable TItem="OrderLineFormModel" @bind-Items="Model.Lines">
        <AdminInlineColumn Title="Product" Field="ProductName"
            DisplayType="Text" Required="true" />
        <AdminInlineColumn Title="Quantity" Field="Quantity"
            DisplayType="Number" Required="true" />
        <AdminInlineColumn Title="Unit Price" Field="UnitPrice"
            DisplayType="Currency" ReadOnly="true" />
        <AdminInlineColumn Title="Line Total" Field="LineTotal"
            DisplayType="Currency" ReadOnly="true" />
        <AdminInlineActions>
            <button @onclick="() => RemoveLine(context)">Remove</button>
        </AdminInlineActions>
    </AdminInlineTable>
    <button type="button" class="btn btn-secondary"
        @onclick="AddLine">+ Add Line</button>
</fieldset>

// Generated: ProductComplianceDashboard.razor (excerpt)
<div class="admin-compliance-dashboard">
    <h3>Requirement Compliance</h3>

    <AdminComplianceTable>
        <AdminComplianceRow Feature="AggregateDefinitionFeature"
            Status="FullyCovered" TestsPassed="4" TestsTotal="4"
            Coverage="92.3%" />
        <AdminComplianceRow Feature="ContentPartsFeature"
            Status="PartiallyCovered" TestsPassed="3" TestsTotal="5"
            Coverage="78.1%" />
        <AdminComplianceRow Feature="ListGenerationFeature"
            Status="FullyCovered" TestsPassed="4" TestsTotal="4"
            Coverage="95.0%" />
    </AdminComplianceTable>

    <AdminComplianceSummary TotalFeatures="3"
        CoveredFeatures="2" PartialFeatures="1" UncoveredFeatures="0"
        OverallCoverage="88.5%" />
</div>