using GB5Shared.DTO.Framework.Login;

namespace CMSBLL.DataSourceProxy;

// The opaque contract a ClientSideFetch-bound block's PropsJson carries under the reserved
// "__dataBinding" key — see SiteDocumentBLL.ResolveDataBindingsAsync. The FE island passes these
// two fields straight through to the public GetBlockData proxy endpoint; it never sees the
// DataSource's EndpointTemplate, auth mode, or Vault path.
public class ClientFetchDescriptorDTO
{
    public string DataSourceCode { get; set; } = string.Empty;
    public string? ParamsJson { get; set; }
}

public interface IDataSourceProxyBLL
{
    // Server-side merge path (BlockDataBindingMode.ServerSideRenderMerge) — called once per bound
    // block from SiteDocumentBLL's tree walk. Returns a flat JSON object string (the mapped
    // response, keyed by ResponseMappingJson's target prop names) to merge into the block's own
    // PropsJson, or null if this block has no binding, the binding isn't ServerSideRenderMerge,
    // or the fetch failed (a dynamic block failing to resolve must not fail the whole page).
    Task<string?> ResolveServerMergePatchAsync(int contentBlockId, LoginDTO loginDTO, CancellationToken ct);

    // Client-side fetch path (BlockDataBindingMode.ClientSideFetch) — returns the opaque
    // descriptor SiteDocumentBLL merges into the block's PropsJson under "__dataBinding", or null
    // if this block has no binding or isn't ClientSideFetch.
    Task<ClientFetchDescriptorDTO?> GetClientFetchDescriptorAsync(int contentBlockId, LoginDTO loginDTO, CancellationToken ct);

    // Client-side fetch path (BlockDataBindingMode.ClientSideFetch) — entered from the public
    // GetBlockData proxy endpoint using the opaque {DataSourceCode, ParamsJson} contract the FE
    // island sent. Same fetch+auth+mapping+cache logic as the server-merge path; the difference
    // is only which caller triggers it and when the failure surfaces (here, as a thrown
    // exception the endpoint turns into an error response, since there's no "just omit this
    // block" fallback once the page has already rendered without it).
    Task<string> ResolveDataAsync(string dataSourceCode, string? paramsJson, LoginDTO loginDTO, CancellationToken ct);

    // Entry point for the public GetBlockData proxy endpoint: resolves domainName -> Site/
    // TenantId via ISiteResolverBLL (the only trusted tenant-context source for an anonymous
    // request — same rule GetSiteDocument follows) and rebases loginDTO onto that tenant before
    // calling ResolveDataAsync, so a tenant-scoped DataSource resolves under its own owner's
    // tenant rather than the caller's. Returns null if the domain doesn't resolve to an active
    // Site — the endpoint turns that into a 404, identical to GetSiteDocument's own handling.
    Task<string?> ResolveDataForDomainAsync(string domainName, string dataSourceCode, string? paramsJson, LoginDTO loginDTO, CancellationToken ct);
}