using AsbCloudApp.Data;
using AsbCloudApp.Services;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

// For more information on enabling Web API for empty projects, visit https://go.microsoft.com/fwlink/?LinkID=397860
namespace AsbCloudWebApi.Controllers
{
    /// <summary>
    /// CRUD контроллер для админки.
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <typeparam name="TService"></typeparam>
    [ApiController]
    [Route("api/[controller]")]
    [Authorize]
    public abstract class CrudController<T, TService> : ControllerBase
        where T : IId
        where TService : ICrudService<T>
    {
        protected readonly TService service;

        public Func<T, CancellationToken, Task<bool>> InsertForbidAsync { get; protected set; } = null;
        public Func<T, CancellationToken, Task<bool>> UpdateForbidAsync { get; protected set; } = null;
        public Func<int, CancellationToken, Task<bool>> DeleteForbidAsync { get; protected set; } = null;

        public CrudController(TService service)
        {
            this.service = service;
        }

        /// <summary>
        /// Получить все записи
        /// </summary>
        /// <param name="token">CancellationToken</param>
        /// <returns>все записи</returns>
        [HttpGet]
        [Permission]
        public virtual async Task<ActionResult<IEnumerable<T>>> GetAllAsync(CancellationToken token)
        {
            var result = await service.GetAllAsync(token).ConfigureAwait(false);
            return Ok(result);
        }

        /// <summary>
        /// Получить одну запись по Id
        /// </summary>
        /// <param name="id">id записи</param>
        /// <param name="token"></param>
        /// <returns>запись</returns>
        [HttpGet("{id}")]
        [Permission]
        public virtual async Task<ActionResult<T>> GetAsync(int id, CancellationToken token)
        {
            var result = await service.GetAsync(id, token).ConfigureAwait(false);
            return Ok(result);
        }

        /// <summary>
        /// Добавить запись
        /// </summary>
        /// <param name="value">запись</param>
        /// <param name="token"></param>
        /// <returns>id</returns>
        [HttpPost]
        [Permission]
        public virtual async Task<ActionResult<int>> InsertAsync([FromBody] T value, CancellationToken token)
        {
            if (InsertForbidAsync is not null && await InsertForbidAsync(value, token))
                return Forbid();

            var result = await service.InsertAsync(value, token).ConfigureAwait(false);
            return Ok(result);
        }

        /// <summary>
        /// Добавить несколько записей<br/>
        /// При невозможности добавить любую из записей, все не будут добавлены.
        /// </summary>
        /// <param name="values">записи</param>
        /// <param name="token"></param>
        /// <returns>id</returns>
        [HttpPost("range")]
        [Permission]
        public virtual async Task<ActionResult<int>> InsertRangeAsync([FromBody] IEnumerable<T> values, CancellationToken token)
        {
            if (!values.Any())
                return BadRequest("there is no values to add");

            if (InsertForbidAsync is not null)            
                foreach (var value in values)                
                    if(await InsertForbidAsync(value, token))
                        return Forbid();

            var result = await service.InsertRangeAsync(values, token).ConfigureAwait(false);
            return Ok(result);
        }

        /// <summary>
        /// Редактировать запись по id
        /// </summary>
        /// <param name="value">запись</param>
        /// <param name="token"></param>
        /// <returns>1 - успешно отредактировано, 0 - нет</returns>
        [HttpPut]
        [Permission]
        public virtual async Task<ActionResult<int>> UpdateAsync([FromBody] T value, CancellationToken token)
        {
            if (UpdateForbidAsync is not null && await UpdateForbidAsync(value, token))
                return Forbid();

            var result = await service.UpdateAsync(value, token).ConfigureAwait(false);
            if (result == ICrudService<T>.ErrorIdNotFound)
                return BadRequest($"id:{value.Id} does not exist in the db");
            return Ok(result);
        }

        /// <summary>
        /// Удалить запись по id
        /// </summary>
        /// <param name="id">id записи</param>
        /// <param name="token"></param>
        /// <returns>1 - успешно удалено, 0 - нет</returns>
        [HttpDelete("{id}")]
        public virtual async Task<ActionResult<int>> DeleteAsync(int id, CancellationToken token)
        {
            if (DeleteForbidAsync is not null && await DeleteForbidAsync(id, token))
                return Forbid();

            var result = await service.DeleteAsync(id, token).ConfigureAwait(false);
            if (result == ICrudService<T>.ErrorIdNotFound)
                return NoContent();
            return Ok(result);
        }
    }
}