using System.Data;
using Dapper;
using InServiceQue.Core.Models;
using InServiceQue.Core.Repositories;
using Npgsql;

namespace InServiceQue.Postgres;

public class TaskRepository: ITaskRepository
{
    private readonly NpgsqlConnection _connection;

    public TaskRepository(string connectionString)
    {
        _connection = new NpgsqlConnection(connectionString);
    }
    
    public void Insert(QueueTask task)
    {
        var sql =
            $"INSERT INTO QUEUE({nameof(QueueTask.Id)}, {nameof(QueueTask.TaskType)}, {nameof(QueueTask.DateCreated)}, {nameof(QueueTask.Payload)}) VALUES (@{nameof(QueueTask.Id)}, @{nameof(QueueTask.TaskType)}, @{nameof(QueueTask.DateCreated)}, @{nameof(QueueTask.Payload)})";
        
        _connection.Execute(sql, task);
    }
    
    public async Task InsertAsync(QueueTask task)
    {
        var sql =
            $"INSERT INTO QUEUE({nameof(QueueTask.Id)}, {nameof(QueueTask.TaskType)}, {nameof(QueueTask.DateCreated)}, {nameof(QueueTask.Payload)}) VALUES (@{nameof(QueueTask.Id)}, @{nameof(QueueTask.TaskType)}, @{nameof(QueueTask.DateCreated)}, @{nameof(QueueTask.Payload)})";
        
        await _connection.ExecuteAsync(sql, task);
    }

    public IDbTransaction StartTransaction()
    {
        return _connection.BeginTransaction();
    }
    
    public async Task<IDbTransaction> StartTransactionAsync()
    {
        return await _connection.BeginTransactionAsync();
    }

    public void CommitTransaction(IDbTransaction tx)
    {
        tx.Commit();
    }
    
    public async Task CommitTransactionAsync(IDbTransaction tx)
    {
        await ((NpgsqlTransaction)tx).CommitAsync();
    }

    public void RollbackTransaction(IDbTransaction tx)
    {
        tx.Rollback();
    }
    
    public async Task RollbackTransactionAsync(IDbTransaction tx)
    {
        await ((NpgsqlTransaction)tx).RollbackAsync();
    }

    public QueueTask? GetNextTask(IDbTransaction tx)
    {
        var sql = $@"select * from QUEUE where 
                order by {nameof(QueueTask.DateCreated)}
                limit 1
                for update skip locked";
        
        return _connection.QuerySingleOrDefault<QueueTask>(sql, tx);
    }
    
    public async Task<QueueTask?> GetNextTaskAsync(IDbTransaction tx)
    {
        var sql = $@"select * from QUEUE 
                order by {nameof(QueueTask.DateCreated)}
                limit 1
                for update skip locked";
        
        return await _connection.QuerySingleOrDefaultAsync<QueueTask>(sql, tx);
    }

    public void SaveTask(QueueTask task, IDbTransaction tx)
    {
        var sql = $@"UPDATE QUEUE 
                    SET 
                    {nameof(QueueTask.DateProcessed)} = @{nameof(QueueTask.DateProcessed)},
                    {nameof(QueueTask.DateClosed)} = @{nameof(QueueTask.DateClosed)},
                    {nameof(QueueTask.Attempts)} = @{nameof(QueueTask.Attempts)},
                    {nameof(QueueTask.Payload)} = @{nameof(QueueTask.Payload)}";
        
        _connection.Execute(sql, task, tx);
    }

    public async Task SaveTaskAsync(QueueTask task, IDbTransaction tx)
    {
        var sql = $@"UPDATE QUEUE 
                SET {nameof(QueueTask.DateProcessed)} = @{nameof(QueueTask.DateProcessed)},
                    {nameof(QueueTask.DateClosed)} = @{nameof(QueueTask.DateClosed)},
                    {nameof(QueueTask.Attempts)} = @{nameof(QueueTask.Attempts)},
                    {nameof(QueueTask.Payload)} = @{nameof(QueueTask.Payload)}";
        
        await _connection.ExecuteAsync(sql, task, tx);
    }
    
    private void ReleaseUnmanagedResources()
    {
        _connection.Dispose();
    }

    public void Dispose()
    {
        ReleaseUnmanagedResources();
        GC.SuppressFinalize(this);
    }

    ~TaskRepository()
    {
        ReleaseUnmanagedResources();
    }
}