using static MFiles.Grpc.Samples.MFilesValues;

namespace MFiles.Grpc.Samples.Recipes;

/// <summary>
/// Recipe "paging": read every document, a page at a time, in object ID order.
/// Arguments: [page size, default 100]
/// </summary>
public static class Paging
{
    /// <summary>Sort key for ascending object ID order.</summary>
    private const int SortByObjectId = -102;

    public static async Task RunAsync(MFilesSettings settings, string[] args)
    {
        int pageSize = RecipeHelpers.IntArg(args, 0, 100);
        await using var connection = await MFilesConnection.ConnectAsync(settings, RecipeHelpers.ClientName);
        var search = new IRPCSearch.IRPCSearchClient(connection.CallInvoker);

        // [START paging]
        // Keyset paging: sort by object ID and ask each page for IDs above the last one seen.
        int lastId = 0, page = 0, total = 0;
        while (true)
        {
            var request = new SearchObjectsRequest
            {
                Conditions =
                {
                    new SearchConditionArray
                    {
                        Value =
                        {
                            IsObjectType(0),
                            IsNotDeleted(),
                            StatusCondition(StatusType.ObjectId, ConditionType.GreaterThan, Integer(lastId)),
                        },
                    },
                },
                Sorting = new SearchResultsSorting
                {
                    Rules = new SortRuleValueArray { Values = { new SortRule { Key = SortByObjectId } } },
                },
                Limit = (uint)pageSize,
            };
            var response = await search.SearchObjectsAsync(request);
            if (response.Results.Count == 0)
                break;

            page++;
            total += response.Results.Count;
            int firstId = response.Results[0].Object.ObjectInfo.ObjId.ItemId.InternalId;
            lastId = response.Results[^1].Object.ObjectInfo.ObjId.ItemId.InternalId;
            Console.WriteLine($"Page {page}: {response.Results.Count} documents, IDs {firstId}-{lastId}");

            if (!response.HasMoreResults)
                break;
        }
        // [END paging]
        Console.WriteLine($"Total: {total} documents in {page} pages");
    }
}