using System.Text;

using FabApprovalWorkerService.Models;
using FabApprovalWorkerService.Utilities;

namespace FabApprovalWorkerService.Services;

public interface IApprovalService {
    Task<IEnumerable<Approval>> GetActiveApprovalsWithNotificationOlderThanFiveDays();
    Task UpdateApproval(Approval approval);
}

public class ApprovalService : IApprovalService {
    private readonly ILogger<ApprovalService> _logger;
    private readonly IDalService _dalService;

    public ApprovalService(ILogger<ApprovalService> logger, IDalService dalService) {
        _logger = logger ?? throw new ArgumentNullException("ILogger not injected");
        _dalService = dalService ?? throw new ArgumentNullException("IDalService not injected");
    }

    public async Task<IEnumerable<Approval>> GetActiveApprovalsWithNotificationOlderThanFiveDays() {
        try {
            _logger.LogInformation($"Attempting to get active approvals with notifications older than five days");

            StringBuilder queryBuilder = new();
            queryBuilder.Append("select * from Approval where ");
            queryBuilder.Append($"ItemStatus=0 and AssignedDate > '{DateTimeOffset.Now.AddDays(-365).DateTime.ToString("yyyy-MM-dd HH:mm:ss")}' and ");
            queryBuilder.Append($"(CompletedDate is null or CompletedDate >= '{DateTimeUtilities.MAX_DT.ToString("yyyy-MM-dd HH:mm")}') and ");
            queryBuilder.Append($"(NotifyDate is null or NotifyDate < '{DateTimeOffset.Now.AddDays(-5).DateTime.ToString("yyyy-MM-dd HH:mm")}')");

            IEnumerable<Approval> approvals = await _dalService.QueryAsync<Approval>(queryBuilder.ToString());

            return approvals;
        } catch (Exception ex) {
            _logger.LogError($"Unable to get active approvals with notifications older than five days, because {ex.Message}");
            throw;
        }
    }

    public async Task UpdateApproval(Approval approval) {
        try {
            _logger.LogInformation("Attempting to update an approval");

            if (approval is null) throw new ArgumentNullException("Approval cannot be null");

            StringBuilder queryBuilder = new();
            queryBuilder.Append($"update Approval set IssueID={approval.IssueID}, RoleName='{approval.RoleName}', ");
            queryBuilder.Append($"SubRole='{approval.SubRole}', UserID={approval.UserID}, SubRoleID={approval.SubRoleID}, ");
            queryBuilder.Append($"ItemStatus={Convert.ToInt32(approval.ItemStatus)}, Step={approval.Step}, ");
            queryBuilder.Append($"NotifyDate='{approval.NotifyDate.ToString("yyyy-MM-dd HH:mm:ss")}', ");
            queryBuilder.Append($"AssignedDate='{approval.AssignedDate.ToString("yyyy-MM-dd HH:mm:ss")}', ");
            queryBuilder.Append($"CompletedDate='{approval.CompletedDate.ToString("yyyy-MM-dd HH:mm:ss")}', ");
            queryBuilder.Append($"Comments='{approval.Comments.Replace("'", "''")}', ");
            queryBuilder.Append($"TaskID={approval.TaskID} ");
            queryBuilder.Append($"where ApprovalID={approval.ApprovalID};");

            int rowsUpdated = await _dalService.ExecuteAsync(queryBuilder.ToString());

            if (rowsUpdated <= 0) throw new Exception("Unable to update approval in database");
        } catch (Exception ex) {
            _logger.LogError($"Approval update failed, because {ex.Message}");
            throw;
        }
    }
}