using SurrealDb.Net;
using TarninaHub.Application.Abstractions;
using TarninaHub.Application.Dtos;

namespace TarninaHub.Infrastructure.Persistence;

public sealed class PartnershipService : IPartnershipService
{
    private const string SelectFields =
        "type::string(id) AS id, type::string(initiator) AS initiator, subject, " +
        "array::map(partners, |$p| type::string($p)) AS partners, status";

    private readonly ISurrealDbClient _client;

    public PartnershipService(ISurrealDbClient client)
    {
        _client = client;
    }

    public async Task<IReadOnlyList<PartnershipResponse>> ListForUserAsync(
        string userId,
        bool isStaff,
        CancellationToken cancellationToken)
    {
        var parameters = new Dictionary<string, object?>();
        var where = string.Empty;

        if (!isStaff)
        {
            var (table, id) = SurrealRecordId.Split(userId);
            where = " WHERE initiator = type::record($table, $id)";
            parameters["table"] = table;
            parameters["id"] = id;
        }

        var response = await _client.RawQuery(
            $"SELECT {SelectFields} FROM partnership{where} ORDER BY subject ASC;",
            parameters,
            cancellationToken);
        response.EnsureAllOks();

        var rows = response.GetValue<List<PartnershipRow>>(0) ?? [];

        return rows.Select(Map).ToList();
    }

    public async Task<PartnershipResponse> CreateAsync(
        string initiatorId,
        CreatePartnershipRequest request,
        CancellationToken cancellationToken)
    {
        var partnershipId = Guid.NewGuid().ToString("N");
        var (initiatorTable, initiatorIdPart) = SurrealRecordId.Split(initiatorId);
        var partners = request.Partners ?? [];
        var parameters = new Dictionary<string, object?>
        {
            ["id"] = partnershipId,
            ["subject"] = request.Subject,
            ["initiatorTable"] = initiatorTable,
            ["initiatorId"] = initiatorIdPart,
        };

        var partnerExpressions = new List<string>(partners.Count);

        for (var i = 0; i < partners.Count; i++)
        {
            var (table, id) = SurrealRecordId.Split(partners[i]);
            parameters[$"table{i}"] = table;
            parameters[$"id{i}"] = id;
            partnerExpressions.Add($"type::record($table{i}, $id{i})");
        }

        var response = await _client.RawQuery(
            "CREATE type::record('partnership', $id) SET " +
            "initiator = type::record($initiatorTable, $initiatorId), subject = $subject, " +
            $"partners = [{string.Join(", ", partnerExpressions)}], status = 'proposed'; " +
            $"SELECT {SelectFields} FROM type::record('partnership', $id) LIMIT 1;",
            parameters,
            cancellationToken);
        response.EnsureAllOks();

        var rows = response.GetValue<List<PartnershipRow>>(1) ?? [];

        return rows.Count > 0
            ? Map(rows[0])
            : throw new InvalidOperationException("Partnership could not be loaded after creation.");
    }

    private static PartnershipResponse Map(PartnershipRow row) => new(
        row.Id,
        row.Initiator,
        row.Subject,
        row.Partners,
        row.Status);
}