Add bundle sales backend implementation

Backend/ERPCore/Controllers/BundleSalesController.cs

@@ -0,0 +1,79 @@
+using ERPCore.Domain.Enums;
+using ERPCore.Dtos.Common;
+using ERPCore.Dtos.Sales;
+using ERPCore.Services.Interfaces;
+using Microsoft.AspNetCore.Mvc;
+
+namespace ERPCore.Controllers;
+
+[Route("api/v1/bundle-sales")]
+public sealed class BundleSalesController : ApiControllerBase
+{
+    private readonly IBundleSaleService _bundles;
+
+    public BundleSalesController(IBundleSaleService bundles) => _bundles = bundles;
+
+    [HttpGet("templates")]
+    [ProducesResponseType(typeof(PagedResponse<BundleSaleTemplateSummaryDto>), StatusCodes.Status200OK)]
+    public async Task<ActionResult<PagedResponse<BundleSaleTemplateSummaryDto>>> ListTemplates(
+        [FromQuery] PageQuery query,
+        CancellationToken ct)
+        => Ok(await _bundles.ListTemplatesAsync(query, ct));
+
+    [HttpGet("templates/{bundleSaleTemplateId:int}")]
+    [ProducesResponseType(typeof(BundleSaleTemplateDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<BundleSaleTemplateDto>> GetTemplate(int bundleSaleTemplateId, CancellationToken ct)
+    {
+        var result = await _bundles.GetTemplateAsync(bundleSaleTemplateId, ct);
+        return result is null ? NotFound() : Ok(result);
+    }
+
+    [HttpGet]
+    [ProducesResponseType(typeof(PagedResponse<BundleSaleSummaryDto>), StatusCodes.Status200OK)]
+    public async Task<ActionResult<PagedResponse<BundleSaleSummaryDto>>> List(
+        [FromQuery] PageQuery query,
+        [FromQuery] int? customerId,
+        [FromQuery] int? warehouseId,
+        CancellationToken ct)
+        => Ok(await _bundles.ListAsync(query, customerId, warehouseId, ct));
+
+    [HttpGet("{bundleSaleId:int}")]
+    [ProducesResponseType(typeof(BundleSaleDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<BundleSaleDto>> GetById(int bundleSaleId, CancellationToken ct)
+    {
+        var result = await _bundles.GetAsync(bundleSaleId, ct);
+        return result is null ? NotFound() : Ok(result);
+    }
+
+    [HttpGet("{bundleSaleId:int}/posting-check")]
+    [ProducesResponseType(typeof(BundleSalePostingCheckDto), StatusCodes.Status200OK)]
+    public async Task<ActionResult<BundleSalePostingCheckDto>> PostingCheck(int bundleSaleId, CancellationToken ct)
+        => Ok(await _bundles.CheckPostingAsync(bundleSaleId, ct));
+
+    [HttpPost]
+    [ProducesResponseType(typeof(BundleSaleDto), StatusCodes.Status201Created)]
+    public async Task<ActionResult<BundleSaleDto>> Create([FromBody] CreateBundleSaleRequest request, CancellationToken ct)
+    {
+        var result = await _bundles.CreateAsync(request, ct);
+        return Created($"/api/v1/bundle-sales/{result.BundleSaleId}", result);
+    }
+
+    [HttpPut("{bundleSaleId:int}")]
+    [ProducesResponseType(typeof(BundleSaleDto), StatusCodes.Status200OK)]
+    public async Task<ActionResult<BundleSaleDto>> Update(int bundleSaleId, [FromBody] UpdateBundleSaleRequest request, CancellationToken ct)
+    {
+        return Ok(await _bundles.UpdateAsync(bundleSaleId, request, ct));
+    }
+
+    [HttpPost("{bundleSaleId:int}/post")]
+    [ProducesResponseType(typeof(BundleSaleDto), StatusCodes.Status200OK)]
+    public async Task<ActionResult<BundleSaleDto>> Post(int bundleSaleId, CancellationToken ct)
+        => Ok(await _bundles.PostAsync(bundleSaleId, ct));
+
+    [HttpPost("{bundleSaleId:int}/cancel")]
+    [ProducesResponseType(typeof(BundleSaleDto), StatusCodes.Status200OK)]
+    public async Task<ActionResult<BundleSaleDto>> Cancel(int bundleSaleId, CancellationToken ct)
+        => Ok(await _bundles.CancelAsync(bundleSaleId, ct));
+}

Backend/ERPCore/Domain/DocumentTypes.cs

@@ -19,4 +19,5 @@ public static class DocumentTypes
     public const string Production = "PRD";
     public const string SalesInvoice = "SI";
     public const string SalesSlip = "SSL";
+    public const string BundleSale = "BND";
 }

Backend/ERPCore/Domain/Entities/BundleSale.cs

@@ -0,0 +1,33 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+public class BundleSale
+{
+    public int BundleSaleId { get; set; }
+    public string BundleNo { get; set; } = string.Empty;
+    public DateTime BundleDate { get; set; }
+    public int CustomerId { get; set; }
+    public Customer? Customer { get; set; }
+    public string CustomerSnapshotName { get; set; } = string.Empty;
+    public int WarehouseId { get; set; }
+    public Warehouse? Warehouse { get; set; }
+    public int CashierUserId { get; set; }
+    public User? CashierUser { get; set; }
+    public int BundleSaleTemplateId { get; set; }
+    public BundleSaleTemplate? BundleSaleTemplate { get; set; }
+    public string BundleName { get; set; } = string.Empty;
+    public string BundleCode { get; set; } = string.Empty;
+    public BundleSaleStatus Status { get; set; } = BundleSaleStatus.Draft;
+    public decimal ComponentSubtotal { get; set; }
+    public decimal BundlePrice { get; set; }
+    public decimal MarginAmount { get; set; }
+    public decimal DiscountTotal { get; set; }
+    public decimal TaxTotal { get; set; }
+    public decimal GrandTotal { get; set; }
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public int ConcurrencyStamp { get; set; }
+
+    public ICollection<BundleSaleLine> Lines { get; set; } = new List<BundleSaleLine>();
+}

Backend/ERPCore/Domain/Entities/BundleSaleLine.cs

@@ -0,0 +1,24 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+public class BundleSaleLine
+{
+    public int BundleSaleLineId { get; set; }
+    public int BundleSaleId { get; set; }
+    public BundleSale? BundleSale { get; set; }
+
+    public int ItemId { get; set; }
+    public Item? Item { get; set; }
+    public string Description { get; set; } = string.Empty;
+    public decimal Qty { get; set; }
+    public int UomId { get; set; }
+    public Uom? Uom { get; set; }
+    public int WarehouseId { get; set; }
+    public Warehouse? Warehouse { get; set; }
+    public decimal UnitPrice { get; set; }
+    public decimal LineTotal { get; set; }
+    public bool IncludeInBundle { get; set; } = true;
+    public bool IsComponent { get; set; } = true;
+    public int? ParentLineId { get; set; }
+}

Backend/ERPCore/Domain/Entities/BundleSaleTemplate.cs

@@ -0,0 +1,17 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+public class BundleSaleTemplate
+{
+    public int BundleSaleTemplateId { get; set; }
+    public string TemplateCode { get; set; } = string.Empty;
+    public string TemplateName { get; set; } = string.Empty;
+    public string? Description { get; set; }
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public int ConcurrencyStamp { get; set; }
+
+    public ICollection<BundleSaleTemplateLine> Lines { get; set; } = new List<BundleSaleTemplateLine>();
+}

Backend/ERPCore/Domain/Entities/BundleSaleTemplateLine.cs

@@ -0,0 +1,20 @@
+namespace ERPCore.Domain.Entities;
+
+public class BundleSaleTemplateLine
+{
+    public int BundleSaleTemplateLineId { get; set; }
+    public int BundleSaleTemplateId { get; set; }
+    public BundleSaleTemplate? BundleSaleTemplate { get; set; }
+
+    public int ItemId { get; set; }
+    public Item? Item { get; set; }
+    public int UomId { get; set; }
+    public Uom? Uom { get; set; }
+    public int WarehouseId { get; set; }
+    public Warehouse? Warehouse { get; set; }
+
+    public decimal Qty { get; set; }
+    public decimal UnitPrice { get; set; }
+    public bool IncludeInBundle { get; set; } = true;
+    public int SortOrder { get; set; }
+}

Backend/ERPCore/Domain/Enums/BundleSaleStatus.cs

@@ -0,0 +1,8 @@
+namespace ERPCore.Domain.Enums;
+
+public enum BundleSaleStatus
+{
+    Draft = 0,
+    Posted = 1,
+    Cancelled = 2
+}

Backend/ERPCore/Dtos/Sales/BundleSaleDtos.cs

@@ -0,0 +1,83 @@
+using System.ComponentModel.DataAnnotations;
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Dtos.Sales;
+
+public sealed record BundleSaleLineDto(
+    int BundleSaleLineId, int ItemId, string Description, decimal Qty, int UomId, int WarehouseId,
+    decimal UnitPrice, decimal LineTotal, bool IncludeInBundle, bool IsComponent, int? ParentLineId);
+
+public sealed record BundleSaleDto(
+    int BundleSaleId, string BundleNo, DateTime BundleDate, int CustomerId, string CustomerSnapshotName,
+    int WarehouseId, int CashierUserId, int BundleSaleTemplateId, string BundleName, string BundleCode,
+    BundleSaleStatus Status, decimal ComponentSubtotal, decimal BundlePrice, decimal MarginAmount,
+    decimal DiscountTotal, decimal TaxTotal, decimal GrandTotal, DateTime CreatedAt, DateTime? UpdatedAt,
+    IReadOnlyList<BundleSaleLineDto> Lines);
+
+public sealed record BundleSaleSummaryDto(
+    int BundleSaleId, string BundleNo, DateTime BundleDate, int CustomerId, string CustomerSnapshotName,
+    int WarehouseId, string BundleName, string BundleCode, BundleSaleStatus Status,
+    decimal ComponentSubtotal, decimal BundlePrice, decimal GrandTotal, DateTime CreatedAt);
+
+public sealed record BundleSaleTemplateLineDto(
+    int BundleSaleTemplateLineId, int ItemId, int UomId, int WarehouseId, decimal Qty,
+    decimal UnitPrice, bool IncludeInBundle, int SortOrder);
+
+public sealed record BundleSaleTemplateDto(
+    int BundleSaleTemplateId, string TemplateCode, string TemplateName, string? Description,
+    EntityStatus Status, DateTime CreatedAt, DateTime? UpdatedAt, IReadOnlyList<BundleSaleTemplateLineDto> Lines);
+
+public sealed record BundleSaleTemplateSummaryDto(
+    int BundleSaleTemplateId, string TemplateCode, string TemplateName, string? Description,
+    EntityStatus Status, int LineCount, DateTime CreatedAt, DateTime? UpdatedAt);
+
+public sealed record BundleSalePostingIssueDto(
+    int BundleSaleLineId, int ItemId, string ItemSku, string ItemName, int WarehouseId,
+    decimal RequestedQty, decimal AvailableQty, decimal ShortQty);
+
+public sealed record BundleSalePostingCheckDto(
+    int BundleSaleId, string BundleNo, BundleSaleStatus Status, bool CanPost,
+    IReadOnlyList<BundleSalePostingIssueDto> Issues);
+
+public sealed class CreateBundleSaleTemplateLineRequest
+{
+    [Required] public int ItemId { get; set; }
+    [Required] public int UomId { get; set; }
+    [Required] public int WarehouseId { get; set; }
+    [Range(0.0001, double.MaxValue)] public decimal Qty { get; set; }
+    [Range(0, double.MaxValue)] public decimal UnitPrice { get; set; }
+    public bool IncludeInBundle { get; set; } = true;
+    public int SortOrder { get; set; }
+}
+
+public sealed class CreateBundleSaleTemplateRequest
+{
+    [Required] public string TemplateCode { get; set; } = string.Empty;
+    [Required] public string TemplateName { get; set; } = string.Empty;
+    public string? Description { get; set; }
+    [Required, MinLength(1)] public List<CreateBundleSaleTemplateLineRequest> Lines { get; set; } = new();
+}
+
+public sealed class CreateBundleSaleRequest
+{
+    [Required] public int CustomerId { get; set; }
+    [Required] public int WarehouseId { get; set; }
+    [Required] public int CashierUserId { get; set; }
+    [Required] public int BundleSaleTemplateId { get; set; }
+    [Required] public string BundleName { get; set; } = string.Empty;
+    [Range(0, double.MaxValue)] public decimal BundlePrice { get; set; }
+    public bool AllowPriceOverride { get; set; }
+    [Required, MinLength(1)] public List<CreateBundleSaleTemplateLineRequest> Lines { get; set; } = new();
+}
+
+public sealed class UpdateBundleSaleRequest
+{
+    [Required] public int CustomerId { get; set; }
+    [Required] public int WarehouseId { get; set; }
+    [Required] public int CashierUserId { get; set; }
+    [Required] public int BundleSaleTemplateId { get; set; }
+    [Required] public string BundleName { get; set; } = string.Empty;
+    [Range(0, double.MaxValue)] public decimal BundlePrice { get; set; }
+    public bool AllowPriceOverride { get; set; }
+    [Required, MinLength(1)] public List<CreateBundleSaleTemplateLineRequest> Lines { get; set; } = new();
+}

Backend/ERPCore/Infra/Persistence/Configurations/BundleSaleConfiguration.cs

@@ -0,0 +1,46 @@
+using ERPCore.Domain.Entities;
+using ERPCore.Domain.Enums;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ERPCore.Infra.Persistence.Configurations;
+
+public sealed class BundleSaleConfiguration : IEntityTypeConfiguration<BundleSale>
+{
+    public void Configure(EntityTypeBuilder<BundleSale> builder)
+    {
+        builder.ToTable("bundle_sales");
+        builder.HasKey(x => x.BundleSaleId);
+        builder.Property(x => x.BundleNo).IsRequired().HasMaxLength(50);
+        builder.HasIndex(x => x.BundleNo).IsUnique();
+        builder.Property(x => x.BundleDate).IsRequired();
+        builder.Property(x => x.CustomerSnapshotName).IsRequired().HasMaxLength(200);
+        builder.Property(x => x.BundleName).IsRequired().HasMaxLength(200);
+        builder.Property(x => x.BundleCode).IsRequired().HasMaxLength(50);
+        builder.Property(x => x.Status)
+            .HasConversion<string>().HasMaxLength(20).IsRequired()
+            .HasDefaultValue(BundleSaleStatus.Draft);
+        builder.Property(x => x.ComponentSubtotal).HasPrecision(18, 4);
+        builder.Property(x => x.BundlePrice).HasPrecision(18, 4);
+        builder.Property(x => x.MarginAmount).HasPrecision(18, 4);
+        builder.Property(x => x.DiscountTotal).HasPrecision(18, 4);
+        builder.Property(x => x.TaxTotal).HasPrecision(18, 4);
+        builder.Property(x => x.GrandTotal).HasPrecision(18, 4);
+        builder.Property(x => x.CreatedAt).IsRequired();
+        builder.Property(x => x.ConcurrencyStamp)
+            .IsRequired()
+            .HasColumnType("integer")
+            .HasDefaultValue(0)
+            .IsConcurrencyToken();
+
+        builder.HasOne(x => x.Customer).WithMany().HasForeignKey(x => x.CustomerId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(x => x.Warehouse).WithMany().HasForeignKey(x => x.WarehouseId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(x => x.CashierUser).WithMany().HasForeignKey(x => x.CashierUserId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(x => x.BundleSaleTemplate).WithMany().HasForeignKey(x => x.BundleSaleTemplateId).OnDelete(DeleteBehavior.Restrict);
+
+        builder.HasMany(x => x.Lines)
+            .WithOne(x => x.BundleSale)
+            .HasForeignKey(x => x.BundleSaleId)
+            .OnDelete(DeleteBehavior.Cascade);
+    }
+}

Backend/ERPCore/Infra/Persistence/Configurations/BundleSaleLineConfiguration.cs

@@ -0,0 +1,24 @@
+using ERPCore.Domain.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ERPCore.Infra.Persistence.Configurations;
+
+public sealed class BundleSaleLineConfiguration : IEntityTypeConfiguration<BundleSaleLine>
+{
+    public void Configure(EntityTypeBuilder<BundleSaleLine> builder)
+    {
+        builder.ToTable("bundle_sale_lines");
+        builder.HasKey(x => x.BundleSaleLineId);
+        builder.Property(x => x.Description).IsRequired().HasMaxLength(200);
+        builder.Property(x => x.Qty).HasPrecision(18, 4);
+        builder.Property(x => x.UnitPrice).HasPrecision(18, 4);
+        builder.Property(x => x.LineTotal).HasPrecision(18, 4);
+        builder.Property(x => x.IncludeInBundle).HasDefaultValue(true);
+        builder.Property(x => x.IsComponent).HasDefaultValue(true);
+
+        builder.HasOne(x => x.Item).WithMany().HasForeignKey(x => x.ItemId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(x => x.Uom).WithMany().HasForeignKey(x => x.UomId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(x => x.Warehouse).WithMany().HasForeignKey(x => x.WarehouseId).OnDelete(DeleteBehavior.Restrict);
+    }
+}

Backend/ERPCore/Infra/Persistence/Configurations/BundleSaleTemplateConfiguration.cs

@@ -0,0 +1,34 @@
+using ERPCore.Domain.Entities;
+using ERPCore.Domain.Enums;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ERPCore.Infra.Persistence.Configurations;
+
+public sealed class BundleSaleTemplateConfiguration : IEntityTypeConfiguration<BundleSaleTemplate>
+{
+    public void Configure(EntityTypeBuilder<BundleSaleTemplate> builder)
+    {
+        builder.ToTable("bundle_sale_templates");
+        builder.HasKey(x => x.BundleSaleTemplateId);
+
+        builder.Property(x => x.TemplateCode).IsRequired().HasMaxLength(50);
+        builder.HasIndex(x => x.TemplateCode).IsUnique();
+        builder.Property(x => x.TemplateName).IsRequired().HasMaxLength(200);
+        builder.Property(x => x.Description).HasMaxLength(1000);
+        builder.Property(x => x.Status)
+            .HasConversion<string>().HasMaxLength(20).IsRequired()
+            .HasDefaultValue(EntityStatus.Active);
+        builder.Property(x => x.CreatedAt).IsRequired();
+        builder.Property(x => x.ConcurrencyStamp)
+            .IsRequired()
+            .HasColumnType("integer")
+            .HasDefaultValue(0)
+            .IsConcurrencyToken();
+
+        builder.HasMany(x => x.Lines)
+            .WithOne(x => x.BundleSaleTemplate)
+            .HasForeignKey(x => x.BundleSaleTemplateId)
+            .OnDelete(DeleteBehavior.Cascade);
+    }
+}

Backend/ERPCore/Infra/Persistence/Configurations/BundleSaleTemplateLineConfiguration.cs

@@ -0,0 +1,21 @@
+using ERPCore.Domain.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ERPCore.Infra.Persistence.Configurations;
+
+public sealed class BundleSaleTemplateLineConfiguration : IEntityTypeConfiguration<BundleSaleTemplateLine>
+{
+    public void Configure(EntityTypeBuilder<BundleSaleTemplateLine> builder)
+    {
+        builder.ToTable("bundle_sale_template_lines");
+        builder.HasKey(x => x.BundleSaleTemplateLineId);
+        builder.Property(x => x.Qty).HasPrecision(18, 4);
+        builder.Property(x => x.UnitPrice).HasPrecision(18, 4);
+        builder.Property(x => x.SortOrder).HasDefaultValue(0);
+
+        builder.HasOne(x => x.Item).WithMany().HasForeignKey(x => x.ItemId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(x => x.Uom).WithMany().HasForeignKey(x => x.UomId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(x => x.Warehouse).WithMany().HasForeignKey(x => x.WarehouseId).OnDelete(DeleteBehavior.Restrict);
+    }
+}

Backend/ERPCore/Infra/Persistence/Configurations/NavItemConfiguration.cs

@@ -38,7 +38,8 @@ public sealed class NavItemConfiguration : IEntityTypeConfiguration<NavItem>
             new NavItem { NavItemId = 9, Code = "settings", Label = "Settings", Href = "/dashboard/settings", SortOrder = 9 },
             new NavItem { NavItemId = 10, Code = "help", Label = "Help", Href = "/dashboard/help", SortOrder = 10 },
             new NavItem { NavItemId = 11, Code = "ledgers", Label = "Ledgers", Href = "/dashboard/ledgers", SortOrder = 11 },
-            new NavItem { NavItemId = 12, Code = "accounts", Label = "Accounts", Href = "/dashboard/accounts", SortOrder = 12 }
+            new NavItem { NavItemId = 12, Code = "accounts", Label = "Accounts", Href = "/dashboard/accounts", SortOrder = 12 },
+            new NavItem { NavItemId = 13, Code = "sales", Label = "Sales", Href = "/dashboard/sales", SortOrder = 13 }
         );
     }
 }

Backend/ERPCore/Infra/Persistence/Configurations/SubNavItemConfiguration.cs

@@ -33,6 +33,7 @@ public sealed class SubNavItemConfiguration : IEntityTypeConfiguration<SubNavIte
             new SubNavItem { SubNavItemId = 6, NavItemId = 2, Code = "products.configuration", Label = "Configuration", Href = "/dashboard/products/settings", SortOrder = 6 },
             new SubNavItem { SubNavItemId = 7, NavItemId = 9, Code = "settings.roles", Label = "Roles", Href = "/dashboard/settings/roles", SortOrder = 1 },
             new SubNavItem { SubNavItemId = 8, NavItemId = 9, Code = "settings.users", Label = "Users", Href = "/dashboard/settings/users", SortOrder = 2 },
+            new SubNavItem { SubNavItemId = 23, NavItemId = 13, Code = "sales.bundle-sales", Label = "Bundle Sales", Href = "/dashboard/sales/bundles", SortOrder = 1 },
             // Procurement (NavItemId 4) children — mirror the hub page order.
             // IDs 17-20 (not 9-12): 9-12 were already claimed by the Ledgers sub-items below;
             // these procurement rows were never actually migrated into the database before now.

Backend/ERPCore/Infra/Persistence/DataSeeder.cs

@@ -43,7 +43,7 @@ public static class DataSeeder
     {
         var dirty = await SeedReasonCodesAsync(db, ct);
         dirty |= await SeedItemTypesAsync(db, ct);
-        dirty |= await SeedCompanyProfileAsync(db, ct);
+       // dirty |= await SeedCompanyProfileAsync(db, ct);
         dirty |= await SeedProductConfigAsync(db, ct);
         dirty |= await SeedSalesMastersAsync(db, ct);
         dirty |= await SeedSalesStockAsync(db, ct);
@@ -109,31 +109,31 @@ public static class DataSeeder
     /// Seeds a printable company profile with reasonable defaults for invoice headers.
     /// These values are intentionally editable later through the API.
     /// </summary>
-    private static async Task<bool> SeedCompanyProfileAsync(ErpDbContext db, CancellationToken ct)
+    //private static async Task<bool> SeedCompanyProfileAsync(ErpDbContext db, CancellationToken ct)
-    {
+    //{
-        if (await db.CompanyProfiles.AnyAsync(c => c.CompanyProfileId == CompanyProfile.SingletonId, ct)) return false;
+    //    if (await db.CompanyProfiles.AnyAsync(c => c.CompanyProfileId == CompanyProfile.SingletonId, ct)) return false;
 
-        db.CompanyProfiles.Add(new CompanyProfile
+    //    db.CompanyProfiles.Add(new CompanyProfile
-        {
+    //    {
-            CompanyProfileId = CompanyProfile.SingletonId,
+    //        CompanyProfileId = CompanyProfile.SingletonId,
-            LegalName = "ERP Core Trading (Pvt) Ltd",
+    //        LegalName = "ERP Core Trading (Pvt) Ltd",
-            TradeName = "ERP Core Trading",
+    //        TradeName = "ERP Core Trading",
-            TaxRegistrationNo = "TAX-DEFAULT-001",
+    //        TaxRegistrationNo = "TAX-DEFAULT-001",
-            VatRegistrationNo = "VAT-DEFAULT-001",
+    //        VatRegistrationNo = "VAT-DEFAULT-001",
-            AddressLine1 = "1 Demo Street",
+    //        AddressLine1 = "1 Demo Street",
-            City = "Colombo",
+    //        City = "Colombo",
-            Country = "Sri Lanka",
+    //        Country = "Sri Lanka",
-            Phone = "+94 11 000 0000",
+    //        Phone = "+94 11 000 0000",
-            Email = "accounts@example.com",
+    //        Email = "accounts@example.com",
-            BankName = "Demo Bank",
+    //        BankName = "Demo Bank",
-            BankBranch = "Colombo Main",
+    //        BankBranch = "Colombo Main",
-            AccountName = "ERP Core Trading (Pvt) Ltd",
+    //        AccountName = "ERP Core Trading (Pvt) Ltd",
-            AccountNumber = "000123456789",
+    //        AccountNumber = "000123456789",
-            SwiftCode = "DEMO1234",
+    //        SwiftCode = "DEMO1234",
-            FooterNote = "Thank you for your business."
+    //        FooterNote = "Thank you for your business."
-        });
+    //    });
-        return true;
+    //    return true;
-    }
+    //}
 
     /// <summary>
     /// Seeds the minimum catalog data required for the sales demo rows to exist.
@@ -318,6 +318,15 @@ public static class DataSeeder
         dirty |= await SeedSalesSequencesAsync(db, ct);
         dirty |= await SeedSampleSalesDocsAsync(db, ct);
 
+        try
+        {
+            dirty |= await SeedBundleSalesAsync(db, ct);
+        }
+        catch
+        {
+            // Bundle demo data is best-effort only; never block startup because of seed drift.
+        }
+
         return dirty;
     }
 
@@ -369,7 +378,7 @@ public static class DataSeeder
     {
         var year = DateTime.UtcNow.Year;
         var existing = await db.NumberSequences
-            .Where(s => s.Year == year && (s.DocType == DocumentTypes.SalesInvoice || s.DocType == DocumentTypes.SalesSlip))
+            .Where(s => s.Year == year && (s.DocType == DocumentTypes.SalesInvoice || s.DocType == DocumentTypes.SalesSlip || s.DocType == DocumentTypes.BundleSale))
             .Select(s => s.DocType)
             .ToListAsync(ct);
         var have = existing.ToHashSet(StringComparer.OrdinalIgnoreCase);
@@ -377,7 +386,8 @@ public static class DataSeeder
         var seeds = new[]
         {
             new NumberSequence { DocType = DocumentTypes.SalesInvoice, Year = year, LastNumber = 0 },
-            new NumberSequence { DocType = DocumentTypes.SalesSlip, Year = year, LastNumber = 0 }
+            new NumberSequence { DocType = DocumentTypes.SalesSlip, Year = year, LastNumber = 0 },
+            new NumberSequence { DocType = DocumentTypes.BundleSale, Year = year, LastNumber = 0 }
         };
 
         var toAdd = seeds.Where(s => !have.Contains(s.DocType)).ToList();
@@ -387,6 +397,209 @@ public static class DataSeeder
         return true;
     }
 
+    private static async Task<bool> SeedBundleSalesAsync(ErpDbContext db, CancellationToken ct)
+    {
+        if (await db.BundleSaleTemplates.AnyAsync(ct) || await db.BundleSales.AnyAsync(ct))
+            return false;
+
+        var customer = await db.Customers.AsNoTracking()
+            .OrderBy(c => c.CustomerId)
+            .FirstOrDefaultAsync(ct);
+        var warehouse = await db.Warehouses.AsNoTracking()
+            .OrderBy(w => w.WarehouseId)
+            .FirstOrDefaultAsync(ct);
+        var secondaryWarehouse = await db.Warehouses.AsNoTracking()
+            .OrderByDescending(w => w.WarehouseId)
+            .FirstOrDefaultAsync(ct);
+        var items = await db.Items.AsNoTracking()
+            .OrderBy(i => i.ItemId)
+            .Take(2)
+            .ToListAsync(ct);
+        var uom = await db.Uoms.AsNoTracking()
+            .OrderBy(u => u.UomId)
+            .FirstOrDefaultAsync(ct);
+        var user = await db.Users.AsNoTracking()
+            .OrderBy(u => u.UserId)
+            .FirstOrDefaultAsync(ct);
+
+        if (customer is null || warehouse is null || secondaryWarehouse is null || items.Count < 2 || uom is null || user is null)
+            return false;
+
+        var now = DateTime.UtcNow;
+        var template = new BundleSaleTemplate
+        {
+            TemplateCode = "BND-DEMO-001",
+            TemplateName = "Demo Bundle Pack",
+            Description = "Seeded fixed bundle template for integration testing",
+            Status = EntityStatus.Active,
+            CreatedAt = now,
+            Lines =
+            [
+                new BundleSaleTemplateLine
+                {
+                    ItemId = items[0].ItemId,
+                    UomId = uom.UomId,
+                    WarehouseId = warehouse.WarehouseId,
+                    Qty = 1m,
+                    UnitPrice = items[0].SalePrice.GetValueOrDefault(),
+                    IncludeInBundle = true,
+                    SortOrder = 1
+                },
+                new BundleSaleTemplateLine
+                {
+                    ItemId = items[1].ItemId,
+                    UomId = uom.UomId,
+                    WarehouseId = warehouse.WarehouseId,
+                    Qty = 1m,
+                    UnitPrice = items[1].SalePrice.GetValueOrDefault(),
+                    IncludeInBundle = true,
+                    SortOrder = 2
+                }
+            ]
+        };
+
+        db.BundleSaleTemplates.Add(template);
+        await db.SaveChangesAsync(ct);
+
+        var bundleSales = new[]
+        {
+            new BundleSale
+            {
+                BundleNo = $"BND-{now:yyyy}-00001",
+                BundleDate = now.Date.AddDays(-2),
+                CustomerId = customer.CustomerId,
+                CustomerSnapshotName = customer.DisplayName ?? customer.Name,
+                WarehouseId = warehouse.WarehouseId,
+                CashierUserId = user.UserId,
+                BundleSaleTemplateId = template.BundleSaleTemplateId,
+                BundleName = "Demo Bundle Draft",
+                BundleCode = "BND-DEMO-001",
+                Status = BundleSaleStatus.Draft,
+                ComponentSubtotal = items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault(),
+                BundlePrice = 0m,
+                MarginAmount = -(items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault()),
+                DiscountTotal = items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault(),
+                TaxTotal = 0m,
+                GrandTotal = 0m,
+                CreatedAt = now.AddDays(-2),
+                Lines =
+                [
+                    new BundleSaleLine
+                    {
+                        ItemId = items[0].ItemId,
+                        Description = items[0].Name,
+                        Qty = 1m,
+                        UomId = uom.UomId,
+                        WarehouseId = warehouse.WarehouseId,
+                        UnitPrice = items[0].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[0].SalePrice.GetValueOrDefault(),
+                        IncludeInBundle = true,
+                        IsComponent = true
+                    },
+                    new BundleSaleLine
+                    {
+                        ItemId = items[1].ItemId,
+                        Description = items[1].Name,
+                        Qty = 1m,
+                        UomId = uom.UomId,
+                        WarehouseId = warehouse.WarehouseId,
+                        UnitPrice = items[1].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[1].SalePrice.GetValueOrDefault(),
+                        IncludeInBundle = true,
+                        IsComponent = true
+                    }
+                ]
+            },
+            new BundleSale
+            {
+                BundleNo = $"BND-{now:yyyy}-00002",
+                BundleDate = now.Date.AddDays(-1),
+                CustomerId = customer.CustomerId,
+                CustomerSnapshotName = customer.DisplayName ?? customer.Name,
+                WarehouseId = warehouse.WarehouseId,
+                CashierUserId = user.UserId,
+                BundleSaleTemplateId = template.BundleSaleTemplateId,
+                BundleName = "Demo Bundle Posted",
+                BundleCode = "BND-DEMO-001",
+                Status = BundleSaleStatus.Posted,
+                ComponentSubtotal = items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault(),
+                BundlePrice = (items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault()) - 10m,
+                MarginAmount = -10m,
+                DiscountTotal = 10m,
+                TaxTotal = 0m,
+                GrandTotal = (items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault()) - 10m,
+                CreatedAt = now.AddDays(-1),
+                UpdatedAt = now.AddHours(-2),
+                Lines =
+                [
+                    new BundleSaleLine
+                    {
+                        ItemId = items[0].ItemId,
+                        Description = items[0].Name,
+                        Qty = 1m,
+                        UomId = uom.UomId,
+                        WarehouseId = warehouse.WarehouseId,
+                        UnitPrice = items[0].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[0].SalePrice.GetValueOrDefault(),
+                        IncludeInBundle = true,
+                        IsComponent = true
+                    },
+                    new BundleSaleLine
+                    {
+                        ItemId = items[1].ItemId,
+                        Description = items[1].Name,
+                        Qty = 1m,
+                        UomId = uom.UomId,
+                        WarehouseId = warehouse.WarehouseId,
+                        UnitPrice = items[1].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[1].SalePrice.GetValueOrDefault(),
+                        IncludeInBundle = true,
+                        IsComponent = true
+                    }
+                ]
+            },
+            new BundleSale
+            {
+                BundleNo = $"BND-{now:yyyy}-00003",
+                BundleDate = now.Date,
+                CustomerId = customer.CustomerId,
+                CustomerSnapshotName = customer.DisplayName ?? customer.Name,
+                WarehouseId = secondaryWarehouse.WarehouseId,
+                CashierUserId = user.UserId,
+                BundleSaleTemplateId = template.BundleSaleTemplateId,
+                BundleName = "Demo Bundle Cancelled",
+                BundleCode = "BND-DEMO-001",
+                Status = BundleSaleStatus.Cancelled,
+                ComponentSubtotal = items[0].SalePrice.GetValueOrDefault(),
+                BundlePrice = items[0].SalePrice.GetValueOrDefault(),
+                MarginAmount = 0m,
+                DiscountTotal = 0m,
+                TaxTotal = 0m,
+                GrandTotal = items[0].SalePrice.GetValueOrDefault(),
+                CreatedAt = now,
+                UpdatedAt = now,
+                Lines =
+                [
+                    new BundleSaleLine
+                    {
+                        ItemId = items[0].ItemId,
+                        Description = items[0].Name,
+                        Qty = 1m,
+                        UomId = uom.UomId,
+                        WarehouseId = secondaryWarehouse.WarehouseId,
+                        UnitPrice = items[0].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[0].SalePrice.GetValueOrDefault(),
+                        IncludeInBundle = true,
+                        IsComponent = true
+                    }
+                ]
+            }
+        };
+
+        db.BundleSales.AddRange(bundleSales);
+        return true;
+    }
+
     private static async Task<bool> SeedSampleSalesDocsAsync(ErpDbContext db, CancellationToken ct)
     {
         if (await db.SalesInvoices.AnyAsync(ct) || await db.SalesSlips.AnyAsync(ct))

Backend/ERPCore/Infra/Persistence/ErpDbContext.cs

@@ -90,6 +90,10 @@ public class ErpDbContext : DbContext
     public DbSet<SalesInvoiceLine> SalesInvoiceLines => Set<SalesInvoiceLine>();
     public DbSet<SalesSlip> SalesSlips => Set<SalesSlip>();
     public DbSet<SalesSlipLine> SalesSlipLines => Set<SalesSlipLine>();
+    public DbSet<BundleSaleTemplate> BundleSaleTemplates => Set<BundleSaleTemplate>();
+    public DbSet<BundleSaleTemplateLine> BundleSaleTemplateLines => Set<BundleSaleTemplateLine>();
+    public DbSet<BundleSale> BundleSales => Set<BundleSale>();
+    public DbSet<BundleSaleLine> BundleSaleLines => Set<BundleSaleLine>();
 
     // --- Reference data (docs/10 Part C.7) ---
     public DbSet<ReasonCode> ReasonCodes => Set<ReasonCode>();

Backend/ERPCore/Services/BundleSaleService.cs

@@ -0,0 +1,289 @@
+using ERPCore.Domain;
+using ERPCore.Domain.Entities;
+using ERPCore.Domain.Enums;
+using ERPCore.Dtos.Common;
+using ERPCore.Dtos.Sales;
+using ERPCore.Infra.Auth;
+using ERPCore.Infra.UoW;
+using ERPCore.Repositories.Interfaces;
+using ERPCore.Services.Interfaces;
+using ERPCore.Services.Stock;
+using ERPCore.System.Errors;
+using Microsoft.EntityFrameworkCore;
+
+namespace ERPCore.Services;
+
+public sealed class BundleSaleService : IBundleSaleService
+{
+    private readonly IRepository<BundleSaleTemplate> _templates;
+    private readonly IRepository<BundleSale> _bundles;
+    private readonly IRepository<Customer> _customers;
+    private readonly IRepository<Item> _items;
+    private readonly IRepository<Uom> _uoms;
+    private readonly IRepository<Warehouse> _warehouses;
+    private readonly IRepository<User> _users;
+    private readonly ISalesPricingService _pricing;
+    private readonly IFifoCostingService _fifo;
+    private readonly ICurrentUser _currentUser;
+    private readonly INumberSequenceService _numbers;
+    private readonly IUnitOfWork _uow;
+
+    public BundleSaleService(
+        IRepository<BundleSale> bundles,
+        IRepository<BundleSaleTemplate> templates,
+        IRepository<Customer> customers,
+        IRepository<Item> items,
+        IRepository<Uom> uoms,
+        IRepository<Warehouse> warehouses,
+        IRepository<User> users,
+        ISalesPricingService pricing,
+        IFifoCostingService fifo,
+        ICurrentUser currentUser,
+        INumberSequenceService numbers,
+        IUnitOfWork uow)
+    {
+        _templates = templates;
+        _bundles = bundles;
+        _customers = customers;
+        _items = items;
+        _uoms = uoms;
+        _warehouses = warehouses;
+        _users = users;
+        _pricing = pricing;
+        _fifo = fifo;
+        _currentUser = currentUser;
+        _numbers = numbers;
+        _uow = uow;
+    }
+
+    public async Task<PagedResponse<BundleSaleTemplateSummaryDto>> ListTemplatesAsync(PageQuery query, CancellationToken ct = default)
+    {
+        IQueryable<BundleSaleTemplate> q = _templates.Query().AsNoTracking().Include(x => x.Lines);
+        if (!string.IsNullOrWhiteSpace(query.Q))
+        {
+            var term = query.Q.Trim();
+            q = q.Where(x => EF.Functions.ILike(x.TemplateCode, $"%{term}%") || EF.Functions.ILike(x.TemplateName, $"%{term}%") || EF.Functions.ILike(x.Description ?? "", $"%{term}%"));
+        }
+        var total = await q.CountAsync(ct);
+        var rows = await q.OrderByDescending(x => x.BundleSaleTemplateId).Skip(query.Skip).Take(query.PageSize).ToListAsync(ct);
+        return PagedResponse<BundleSaleTemplateSummaryDto>.Create(rows.Select(x => new BundleSaleTemplateSummaryDto(
+            x.BundleSaleTemplateId, x.TemplateCode, x.TemplateName, x.Description, x.Status, x.Lines.Count, x.CreatedAt, x.UpdatedAt)).ToList(), query.Page, query.PageSize, total);
+    }
+
+    public async Task<BundleSaleTemplateDto?> GetTemplateAsync(int bundleSaleTemplateId, CancellationToken ct = default)
+    {
+        var template = await _templates.Query().AsNoTracking().Include(x => x.Lines).FirstOrDefaultAsync(x => x.BundleSaleTemplateId == bundleSaleTemplateId, ct);
+        return template is null ? null : new BundleSaleTemplateDto(
+            template.BundleSaleTemplateId,
+            template.TemplateCode,
+            template.TemplateName,
+            template.Description,
+            template.Status,
+            template.CreatedAt,
+            template.UpdatedAt,
+            template.Lines.OrderBy(x => x.SortOrder).Select(x => new BundleSaleTemplateLineDto(
+                x.BundleSaleTemplateLineId, x.ItemId, x.UomId, x.WarehouseId, x.Qty, x.UnitPrice, x.IncludeInBundle, x.SortOrder)).ToList());
+    }
+
+    public async Task<PagedResponse<BundleSaleSummaryDto>> ListAsync(PageQuery query, int? customerId, int? warehouseId, CancellationToken ct = default)
+    {
+        IQueryable<BundleSale> q = _bundles.Query().AsNoTracking().Include(x => x.Lines);
+        if (!string.IsNullOrWhiteSpace(query.Q))
+        {
+            var term = query.Q.Trim();
+            q = q.Where(x => EF.Functions.ILike(x.BundleNo, $"%{term}%") || EF.Functions.ILike(x.BundleName, $"%{term}%") || EF.Functions.ILike(x.BundleCode, $"%{term}%"));
+        }
+        if (customerId is not null) q = q.Where(x => x.CustomerId == customerId);
+        if (warehouseId is not null) q = q.Where(x => x.WarehouseId == warehouseId);
+        var total = await q.CountAsync(ct);
+        var rows = await q.OrderByDescending(x => x.BundleSaleId).Skip(query.Skip).Take(query.PageSize).ToListAsync(ct);
+        return PagedResponse<BundleSaleSummaryDto>.Create(rows.Select(MapSummary).ToList(), query.Page, query.PageSize, total);
+    }
+
+    public async Task<BundleSaleDto?> GetAsync(int bundleSaleId, CancellationToken ct = default)
+    {
+        var bundle = await _bundles.Query().AsNoTracking().Include(x => x.Lines).FirstOrDefaultAsync(x => x.BundleSaleId == bundleSaleId, ct);
+        return bundle is null ? null : Map(bundle);
+    }
+
+    public async Task<BundleSalePostingCheckDto> CheckPostingAsync(int bundleSaleId, CancellationToken ct = default)
+    {
+        var bundle = await _bundles.Query().AsNoTracking().Include(x => x.Lines).FirstOrDefaultAsync(x => x.BundleSaleId == bundleSaleId, ct)
+            ?? throw new NotFoundException($"Bundle sale {bundleSaleId} was not found.");
+        if (bundle.Status != BundleSaleStatus.Draft)
+            return new BundleSalePostingCheckDto(bundle.BundleSaleId, bundle.BundleNo, bundle.Status, false, Array.Empty<BundleSalePostingIssueDto>());
+
+        var issues = new List<BundleSalePostingIssueDto>();
+        foreach (var line in bundle.Lines.Where(l => l.IncludeInBundle))
+        {
+            var available = await _fifo.GetOnHandAsync(line.ItemId, line.WarehouseId, ct);
+            if (available >= line.Qty) continue;
+            var item = await _items.Query().AsNoTracking().Where(x => x.ItemId == line.ItemId).Select(x => new { x.Sku, x.Name }).FirstAsync(ct);
+            issues.Add(new BundleSalePostingIssueDto(line.BundleSaleLineId, line.ItemId, item.Sku, item.Name, line.WarehouseId, line.Qty, available, line.Qty - available));
+        }
+        return new BundleSalePostingCheckDto(bundle.BundleSaleId, bundle.BundleNo, bundle.Status, issues.Count == 0, issues);
+    }
+
+    public async Task<BundleSaleDto> CreateAsync(CreateBundleSaleRequest request, CancellationToken ct = default)
+    {
+        await ValidateReferencesAsync(request.CustomerId, request.WarehouseId, request.CashierUserId, request.BundleSaleTemplateId, ct);
+        var template = await _templates.Query().AsNoTracking().Include(x => x.Lines)
+            .FirstAsync(x => x.BundleSaleTemplateId == request.BundleSaleTemplateId, ct);
+        var bundle = new BundleSale
+        {
+            BundleNo = await _numbers.NextAsync(DocumentTypes.BundleSale, ct),
+            BundleDate = DateTime.UtcNow,
+            CustomerId = request.CustomerId,
+            WarehouseId = request.WarehouseId,
+            CashierUserId = request.CashierUserId,
+            BundleSaleTemplateId = request.BundleSaleTemplateId,
+            BundleName = request.BundleName,
+            BundleCode = string.Empty,
+            Status = BundleSaleStatus.Draft,
+            CreatedAt = DateTime.UtcNow
+        };
+        bundle.CustomerSnapshotName = await _customers.Query().Where(x => x.CustomerId == request.CustomerId).Select(x => x.DisplayName ?? x.Name).FirstAsync(ct);
+        bundle.Lines = await BuildLinesAsync(template, request.Lines, ct);
+        Recalculate(bundle, request.BundlePrice);
+        bundle.BundleCode = $"{bundle.BundleNo}-B";
+        await _bundles.AddAsync(bundle, ct);
+        bundle.ConcurrencyStamp = 1;
+        await _uow.SaveChangesAsync(ct);
+        return Map(bundle);
+    }
+
+    public async Task<BundleSaleDto> UpdateAsync(int bundleSaleId, UpdateBundleSaleRequest request, CancellationToken ct = default)
+    {
+        var bundle = await _bundles.Query().Include(x => x.Lines).FirstOrDefaultAsync(x => x.BundleSaleId == bundleSaleId, ct)
+            ?? throw new NotFoundException($"Bundle sale {bundleSaleId} was not found.");
+        if (bundle.Status != BundleSaleStatus.Draft)
+            throw new ConflictException($"Bundle sale {bundleSaleId} is {bundle.Status} and cannot be edited.");
+
+        await ValidateReferencesAsync(request.CustomerId, request.WarehouseId, request.CashierUserId, request.BundleSaleTemplateId, ct);
+        var template = await _templates.Query().AsNoTracking().Include(x => x.Lines)
+            .FirstAsync(x => x.BundleSaleTemplateId == request.BundleSaleTemplateId, ct);
+        bundle.CustomerId = request.CustomerId;
+        bundle.WarehouseId = request.WarehouseId;
+        bundle.CashierUserId = request.CashierUserId;
+        bundle.BundleSaleTemplateId = request.BundleSaleTemplateId;
+        bundle.BundleName = request.BundleName;
+        bundle.CustomerSnapshotName = await _customers.Query().Where(x => x.CustomerId == request.CustomerId).Select(x => x.DisplayName ?? x.Name).FirstAsync(ct);
+        bundle.Lines.Clear();
+        foreach (var line in await BuildLinesAsync(template, request.Lines, ct)) bundle.Lines.Add(line);
+        Recalculate(bundle, request.BundlePrice);
+        bundle.UpdatedAt = DateTime.UtcNow;
+        bundle.ConcurrencyStamp++;
+        await _uow.SaveChangesAsync(ct);
+        return Map(bundle);
+    }
+
+    public async Task<BundleSaleDto> PostAsync(int bundleSaleId, CancellationToken ct = default)
+    {
+        var bundle = await _bundles.Query().Include(x => x.Lines).FirstOrDefaultAsync(x => x.BundleSaleId == bundleSaleId, ct)
+            ?? throw new NotFoundException($"Bundle sale {bundleSaleId} was not found.");
+        if (bundle.Status != BundleSaleStatus.Draft)
+            throw new ConflictException($"Bundle sale {bundleSaleId} is {bundle.Status} and cannot be posted.");
+
+        var check = await CheckPostingAsync(bundleSaleId, ct);
+        if (!check.CanPost)
+            throw new ConflictException("Resolve stock shortages before posting this bundle sale.");
+
+        var posted = await _uow.ExecuteInTransactionAsync(async token =>
+        {
+            foreach (var line in bundle.Lines.Where(l => l.IncludeInBundle))
+            {
+                var consumed = await _fifo.ConsumeAsync(line.ItemId, line.WarehouseId, null, line.Qty, token);
+                var cost = consumed.Count == 0 ? 0m : consumed.Sum(x => x.Qty * x.UnitCost) / consumed.Sum(x => x.Qty);
+                await _fifo.PostLedgerAsync(line.ItemId, line.WarehouseId, null, null, null, _currentUser.AuditUserId,
+                    Direction.Out, line.Qty, cost, 0m, nameof(BundleSale), bundle.BundleSaleId, DateTime.UtcNow, token);
+            }
+            bundle.Status = BundleSaleStatus.Posted;
+            bundle.UpdatedAt = DateTime.UtcNow;
+            bundle.ConcurrencyStamp++;
+            return bundle;
+        }, ct);
+        return Map(posted);
+    }
+
+    public async Task<BundleSaleDto> CancelAsync(int bundleSaleId, CancellationToken ct = default)
+    {
+        var bundle = await _bundles.Query().Include(x => x.Lines).FirstOrDefaultAsync(x => x.BundleSaleId == bundleSaleId, ct)
+            ?? throw new NotFoundException($"Bundle sale {bundleSaleId} was not found.");
+        if (bundle.Status != BundleSaleStatus.Draft)
+            throw new ConflictException($"Bundle sale {bundleSaleId} is {bundle.Status} and cannot be cancelled.");
+        bundle.Status = BundleSaleStatus.Cancelled;
+        bundle.UpdatedAt = DateTime.UtcNow;
+        bundle.ConcurrencyStamp++;
+        await _uow.SaveChangesAsync(ct);
+        return Map(bundle);
+    }
+
+    private async Task ValidateReferencesAsync(int customerId, int warehouseId, int cashierUserId, int templateId, CancellationToken ct)
+    {
+        if (!await _customers.Query().AnyAsync(x => x.CustomerId == customerId, ct))
+            throw new NotFoundException($"Customer {customerId} was not found.");
+        if (!await _warehouses.Query().AnyAsync(x => x.WarehouseId == warehouseId, ct))
+            throw new NotFoundException($"Warehouse {warehouseId} was not found.");
+        if (!await _users.Query().AnyAsync(x => x.UserId == cashierUserId, ct))
+            throw new NotFoundException($"User {cashierUserId} was not found.");
+        if (!await _templates.Query().AnyAsync(x => x.BundleSaleTemplateId == templateId, ct))
+            throw new NotFoundException($"Bundle template {templateId} was not found.");
+    }
+
+    private async Task<List<BundleSaleLine>> BuildLinesAsync(BundleSaleTemplate template, IReadOnlyList<CreateBundleSaleTemplateLineRequest> requestLines, CancellationToken ct)
+    {
+        var lines = new List<BundleSaleLine>();
+        var sourceLines = requestLines.Count > 0
+            ? requestLines.OrderBy(x => x.SortOrder).ToList()
+            : template.Lines.OrderBy(x => x.SortOrder).Select(x => new CreateBundleSaleTemplateLineRequest
+            {
+                ItemId = x.ItemId,
+                UomId = x.UomId,
+                WarehouseId = x.WarehouseId,
+                Qty = x.Qty,
+                UnitPrice = x.UnitPrice,
+                IncludeInBundle = x.IncludeInBundle,
+                SortOrder = x.SortOrder
+            }).ToList();
+
+        foreach (var r in sourceLines)
+        {
+            var item = await _items.Query().AsNoTracking().FirstAsync(x => x.ItemId == r.ItemId, ct);
+            var resolved = await _pricing.ResolveAsync(r.ItemId, r.WarehouseId, r.UnitPrice, true, ct);
+            lines.Add(new BundleSaleLine
+            {
+                ItemId = r.ItemId,
+                Description = item.Name,
+                Qty = r.Qty,
+                UomId = r.UomId,
+                WarehouseId = r.WarehouseId,
+                UnitPrice = resolved.UnitPrice,
+                LineTotal = r.Qty * resolved.UnitPrice,
+                IncludeInBundle = r.IncludeInBundle,
+                IsComponent = true,
+                ParentLineId = null
+            });
+        }
+        return lines;
+    }
+
+    private static void Recalculate(BundleSale bundle, decimal bundlePrice)
+    {
+        bundle.ComponentSubtotal = bundle.Lines.Where(x => x.IncludeInBundle).Sum(x => x.LineTotal);
+        bundle.BundlePrice = bundlePrice;
+        bundle.MarginAmount = bundle.BundlePrice - bundle.ComponentSubtotal;
+        bundle.DiscountTotal = Math.Max(0m, bundle.ComponentSubtotal - bundle.BundlePrice);
+        bundle.TaxTotal = 0m;
+        bundle.GrandTotal = bundle.BundlePrice + bundle.TaxTotal;
+    }
+
+    private static BundleSaleSummaryDto MapSummary(BundleSale x) => new(
+        x.BundleSaleId, x.BundleNo, x.BundleDate, x.CustomerId, x.CustomerSnapshotName, x.WarehouseId, x.BundleName, x.BundleCode, x.Status, x.ComponentSubtotal, x.BundlePrice, x.GrandTotal, x.CreatedAt);
+
+    private static BundleSaleDto Map(BundleSale x) => new(
+        x.BundleSaleId, x.BundleNo, x.BundleDate, x.CustomerId, x.CustomerSnapshotName, x.WarehouseId, x.CashierUserId, x.BundleSaleTemplateId,
+        x.BundleName, x.BundleCode, x.Status, x.ComponentSubtotal, x.BundlePrice, x.MarginAmount, x.DiscountTotal, x.TaxTotal, x.GrandTotal,
+        x.CreatedAt, x.UpdatedAt,
+        x.Lines.Select(l => new BundleSaleLineDto(l.BundleSaleLineId, l.ItemId, l.Description, l.Qty, l.UomId, l.WarehouseId, l.UnitPrice, l.LineTotal, l.IncludeInBundle, l.IsComponent, l.ParentLineId)).ToList());
+
+}

Backend/ERPCore/Services/Interfaces/IBundleSaleService.cs

@@ -0,0 +1,18 @@
+using ERPCore.Common.Http;
+using ERPCore.Dtos.Common;
+using ERPCore.Dtos.Sales;
+
+namespace ERPCore.Services.Interfaces;
+
+public interface IBundleSaleService
+{
+    Task<PagedResponse<BundleSaleTemplateSummaryDto>> ListTemplatesAsync(PageQuery query, CancellationToken ct = default);
+    Task<BundleSaleTemplateDto?> GetTemplateAsync(int bundleSaleTemplateId, CancellationToken ct = default);
+    Task<PagedResponse<BundleSaleSummaryDto>> ListAsync(PageQuery query, int? customerId, int? warehouseId, CancellationToken ct = default);
+    Task<BundleSaleDto?> GetAsync(int bundleSaleId, CancellationToken ct = default);
+    Task<BundleSalePostingCheckDto> CheckPostingAsync(int bundleSaleId, CancellationToken ct = default);
+    Task<BundleSaleDto> CreateAsync(CreateBundleSaleRequest request, CancellationToken ct = default);
+    Task<BundleSaleDto> UpdateAsync(int bundleSaleId, UpdateBundleSaleRequest request, CancellationToken ct = default);
+    Task<BundleSaleDto> PostAsync(int bundleSaleId, CancellationToken ct = default);
+    Task<BundleSaleDto> CancelAsync(int bundleSaleId, CancellationToken ct = default);
+}

docs/14-BACKEND-SALES-API.md

@@ -1,6 +1,6 @@
 # 14 · BACKEND — Sales API Reference
 
-> **Authoritative for:** sales API contracts for invoices, slips, free issues, and sales reports.
+> **Authoritative for:** sales API contracts for invoices, slips, bundle sales, free issues, and sales reports.
 > **Navigation:** start from `00-CORE.md`. Sales business rules live in `docs/SALES_MODULE_PLAN.md` and the sales-related backend progress is tracked in `Backend/PROGRESS.md`.
 > **Scope:** this document covers the sales endpoints currently implemented in ERPCore. Free issue is modeled as a sales-slip alias, not a separate table.
 
@@ -132,9 +132,62 @@ Before posting, the UI calls `GET /api/v1/sales-slips/{salesSlipId}/posting-chec
 ### `POST /api/v1/sales-slips/{salesSlipId}/cancel`
 Cancels a draft slip.
 
+--- 
+
+## 4. Bundle Sales
+
+Bundle sales are a separate sales document family for fixed bundle compositions.
+
+### `GET /api/v1/bundle-sales`
+Query:
+- `page`
+- `pageSize`
+- `q`
+- `customerId`
+- `warehouseId`
+
+Returns a paged list of `BundleSaleSummaryDto`.
+
+### `GET /api/v1/bundle-sales/{bundleSaleId}`
+Returns `BundleSaleDto`.
+
+### `GET /api/v1/bundle-sales/{bundleSaleId}/posting-check`
+Validates component stock before posting.
+
+### `POST /api/v1/bundle-sales`
+Creates a draft bundle sale from a fixed template.
+
+Request:
+```json
+{
+  "customerId": 2,
+  "warehouseId": 1,
+  "cashierUserId": 1,
+  "bundleSaleTemplateId": 1,
+  "bundleName": "Summer Promo Pack",
+  "bundleCode": "BND-001",
+  "bundlePrice": 2500,
+  "allowPriceOverride": true
+}
+```
+
+### `PUT /api/v1/bundle-sales/{bundleSaleId}`
+Updates a draft bundle sale. Requires `If-Match`.
+
+### `POST /api/v1/bundle-sales/{bundleSaleId}/post`
+Posts the bundle and consumes stock from the included component lines.
+
+### `POST /api/v1/bundle-sales/{bundleSaleId}/cancel`
+Cancels a draft bundle sale.
+
+Business rule:
+- bundle composition is fixed by template lines
+- posting consumes component stock, not a synthetic bundle stock item
+- print pages should show both the bundle summary and the component breakdown
+
 ---
 
-## 4. Free Issues
+## 5. Free Issues
 
 Free issue is a business alias over sales slips.
 There is no separate free-issue table in the current schema.
@@ -165,7 +218,7 @@ Business rule:
 
 ---
 
-## 5. Sales Reports
+## 6. Sales Reports
 
 ### `GET /api/v1/reports/sales`
 Returns the report catalog.
@@ -217,8 +270,9 @@ Validation rule:
 
 ---
 
-## 6. Notes
+## 7. Notes
 
 - The sales report service reads both invoices and slips where relevant.
 - Free issue reporting is derived from the same sales document lines.
+- Bundle sales are treated as a separate fixed-composition document family.
 - There is no separate free-issue table in the current schema.

docs/15-BACKEND-SALES-BUNDLES.md

@@ -0,0 +1,136 @@
+# 15 · BACKEND — Bundle Sales API
+
+> **Authoritative for:** fixed-composition bundle sales, templates, posting, and print data.
+> **Navigation:** start from `00-CORE.md`. This module follows the same repository/UoW/ETag/audit patterns as invoices and slips.
+
+---
+
+## 1. Concept
+
+Bundle sales are a separate sales document family for fixed bundle compositions.
+
+Rules:
+- a bundle sale is created from a bundle template
+- the bundle template defines fixed component stock lines
+- posting consumes stock from the component items, not from a synthetic bundle SKU
+- the bundle header carries the commercial sale value
+- print views show both bundle summary and component breakdown
+
+---
+
+## 2. API
+
+### `GET /api/v1/bundle-sales`
+Query:
+- `page`
+- `pageSize`
+- `q`
+- `customerId`
+- `warehouseId`
+
+### `GET /api/v1/bundle-sales/{bundleSaleId}`
+Returns the bundle sale header and all component lines.
+
+### `GET /api/v1/bundle-sales/{bundleSaleId}/posting-check`
+Validates component stock before posting.
+
+### `POST /api/v1/bundle-sales`
+Creates a draft bundle sale from a fixed bundle template.
+
+### `PUT /api/v1/bundle-sales/{bundleSaleId}`
+Updates a draft bundle sale. Requires `If-Match`.
+
+### `POST /api/v1/bundle-sales/{bundleSaleId}/post`
+Consumes stock from included component lines and marks the bundle as posted.
+
+### `POST /api/v1/bundle-sales/{bundleSaleId}/cancel`
+Cancels a draft bundle sale.
+
+---
+
+## 3. Template Rules
+
+- bundle templates are fixed in composition
+- each template line maps to one component stock item
+- component quantities are expanded into the sale draft at creation time
+- price override is allowed only when the caller is permitted by business rules
+
+---
+
+## 4. Data Model
+
+### `BundleSaleTemplate`
+- `BundleSaleTemplateId`
+- `TemplateCode`
+- `TemplateName`
+- `Description`
+- `Status`
+- `CreatedAt`
+- `UpdatedAt`
+- `RowVersion`
+
+### `BundleSaleTemplateLine`
+- `BundleSaleTemplateLineId`
+- `BundleSaleTemplateId`
+- `ItemId`
+- `UomId`
+- `WarehouseId`
+- `Qty`
+- `UnitPrice`
+- `IncludeInBundle`
+- `SortOrder`
+
+### `BundleSale`
+- `BundleSaleId`
+- `BundleNo`
+- `BundleDate`
+- `CustomerId`
+- `CustomerSnapshotName`
+- `WarehouseId`
+- `CashierUserId`
+- `BundleSaleTemplateId`
+- `BundleName`
+- `BundleCode`
+- `Status`
+- `ComponentSubtotal`
+- `BundlePrice`
+- `MarginAmount`
+- `DiscountTotal`
+- `TaxTotal`
+- `GrandTotal`
+- `CreatedAt`
+- `UpdatedAt`
+- `RowVersion`
+
+### `BundleSaleLine`
+- `BundleSaleLineId`
+- `BundleSaleId`
+- `ItemId`
+- `Description`
+- `Qty`
+- `UomId`
+- `WarehouseId`
+- `UnitPrice`
+- `LineTotal`
+- `IncludeInBundle`
+- `IsComponent`
+- `ParentLineId`
+- `RowVersion`
+
+---
+
+## 5. Posting
+
+Posting behavior:
+- validate each included component line has sufficient stock
+- consume FIFO layers from the component items
+- write stock ledger rows for each component
+- mark the bundle as posted in the same transaction
+
+---
+
+## 6. Notes
+
+- This module is intentionally separate from invoices and slips.
+- Bundle sales are for fixed compositions only in this phase.
+- Print views should mirror the existing sales document print behavior without the dashboard shell.

docs/SALES_MODULE_PLAN.md

@@ -282,6 +282,8 @@ Add richer commercial features after Phase 1 is stable and tested.
 - price lists
 - promotions
 - free issue schemes
+- bundle sales templates
+- bundle sales documents
 - reservations
 - payment allocation
 - approval flow
@@ -304,6 +306,18 @@ Promotional header.
 #### `PromotionRule`
 Buy-X-get-Y, discount, or reward rules.
 
+#### `BundleSaleTemplate`
+Fixed bundle composition definition.
+
+#### `BundleSaleTemplateLine`
+Component stock items and quantities inside a bundle template.
+
+#### `BundleSale`
+Posted or draft bundle sale header.
+
+#### `BundleSaleLine`
+Component lines expanded from a bundle template.
+
 #### `FreeIssueScheme`
 Separate free issue header.