using AutoMapper;
using MediatR;
using ExpenseTracker.Application.Common.Interfaces.Repositories;
using ExpenseTracker.Application.Common.Interfaces.Services;

namespace ExpenseTracker.Application.Accounts.Queries.Charts.GetExpenseBarChart;

public class GetExpenseBarChartQueryHandler : IRequestHandler<GetExpenseBarChartQuery, DailyTransactionsBarChart>
{
    private readonly IMapper _mapper;
    private readonly IAccountRepository _accountRepository;
    private readonly ITransactionRepository _transactionRepository;
    private readonly ISessionUserService _sessionUserService;

    public GetExpenseBarChartQueryHandler(
        IMapper mapper,
        IAccountRepository repository,
        ITransactionRepository transactionRepository,
        ISessionUserService sessionUserService)
    {
        _mapper = mapper;
        _accountRepository = repository;
        _sessionUserService = sessionUserService;
        _transactionRepository = transactionRepository;
    }

    public async Task<DailyTransactionsBarChart> Handle(GetExpenseBarChartQuery request, CancellationToken cancellationToken)
    {
        var entities = _transactionRepository.Queryable
            .Where(e =>
                e.AccountId == request.AccountId &&
                e.Amount < 0)
            .ToList()
            .Where(e =>
                DateOnly.FromDateTime(e.Time.DateTime) >= request.FromDate &&
                DateOnly.FromDateTime(e.Time.DateTime) < request.ToDate)
            .OrderBy(e => e.Time);

        var groupsByDate = entities.GroupBy(e => e.Time.Date, t => t.Amount);

        return new DailyTransactionsBarChart(groupsByDate, request.FromDate, request.ToDate);
    }
}