using Distribution.Infra.UoW;

namespace Distribution.Features.ExpenseVendor;

public record PagedExpenseVendorsResponse(List<ExpenseVendorResponse> Items, int Page, int PageSize, int Total);

public class ExpenseVendorService(IExpenseVendorRepository repo, IUnitOfWork uow)
{
    private static ExpenseVendorResponse Map(Models.ExpenseVendor v) =>
        new(v.Id, v.Name, v.ContactInfo, v.IsActive);

    public async Task<PagedExpenseVendorsResponse> ListAsync(string? search, int page, int pageSize)
    {
        if (page < 1) page = 1;
        if (pageSize < 1 || pageSize > 200) pageSize = 50;

        search = string.IsNullOrWhiteSpace(search) ? null : search.Trim();
        var items = await repo.ListAsync(search, page, pageSize);
        var total = await repo.CountAsync(search);
        return new PagedExpenseVendorsResponse(items.Select(Map).ToList(), page, pageSize, total);
    }

    public async Task<ExpenseVendorResponse> CreateAsync(CreateExpenseVendorRequest request, CancellationToken ct = default)
    {
        var name = (request.Name ?? "").Trim();
        if (string.IsNullOrEmpty(name)) throw new InvalidOperationException("Name is required");
        if (await repo.NameExistsAsync(name, null))
            throw new InvalidOperationException("A vendor with this name already exists");

        var entity = new Models.ExpenseVendor { Name = name, ContactInfo = request.ContactInfo };

        await uow.BeginAsync(ct);
        try { await repo.AddAsync(entity); await uow.CommitAsync(ct); }
        catch { await uow.RollbackAsync(ct); throw; }

        return Map(entity);
    }

    public async Task<ExpenseVendorResponse?> UpdateAsync(Guid id, UpdateExpenseVendorRequest request, CancellationToken ct = default)
    {
        var entity = await repo.GetByIdAsync(id);
        if (entity is null) return null;

        var name = (request.Name ?? "").Trim();
        if (string.IsNullOrEmpty(name)) throw new InvalidOperationException("Name is required");
        if (await repo.NameExistsAsync(name, id))
            throw new InvalidOperationException("A vendor with this name already exists");

        entity.Name = name;
        entity.ContactInfo = request.ContactInfo;
        entity.IsActive = request.IsActive;

        await uow.BeginAsync(ct);
        try { repo.Update(entity); await uow.CommitAsync(ct); }
        catch { await uow.RollbackAsync(ct); throw; }

        return Map(entity);
    }
}