using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using BlueWest.Data;
using BlueWest.WebApi.EF;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;

namespace BlueWest.WebApi.Controllers
{
    /// <summary>
    /// Controller responsible to get countryId data
    /// </summary>
    [ApiController]
    [Route("[controller]")]
    public class CountryController : ControllerBase
    {
        private readonly CountryDbContext _dbContext;

        /// <summary>
        /// Controller responsible for handling countryId data in the Country table
        /// </summary>
        /// <param name="dbContext"></param>
        public CountryController(CountryDbContext dbContext)
        {
            _dbContext = dbContext;
        }

        

        /// <summary>
        /// Get countries
        /// </summary>
        /// <returns></returns>
        [ProducesResponseType(StatusCodes.Status200OK)]
        [ProducesResponseType(StatusCodes.Status404NotFound)]
        [HttpGet]
        public ActionResult GetCountries()
        {
            var array = _dbContext
                .Countries
                .Select(x => new CountryUnique(x))
                .ToArray();

            return Ok(array);

        }

        
        /// <summary>
        /// Get Country by Id
        /// </summary>
        /// <param name="countryId">ISO 3166-1 countryId numeric code</param>
        /// <returns></returns>
        [ProducesResponseType(StatusCodes.Status200OK)]
        [ProducesResponseType(StatusCodes.Status404NotFound)]
        [HttpGet("{countryId}", Name = nameof(GetCountryById))]
        public ActionResult GetCountryById(int countryId)
        {
            var country = _dbContext.Countries
                .Where(x => x.Id == countryId)
                .Select(x => new CountryUnique(x))
                .FirstOrDefault();
                

            if (country != null)
            {
                return Ok(country);
            }

            return new NotFoundResult();
        }


        /// <summary>
        /// Get currencies of a countryId
        /// </summary>
        /// <param name="countryId"></param>
        /// <returns></returns>
        [ProducesResponseType(StatusCodes.Status200OK)]
        [ProducesResponseType(StatusCodes.Status404NotFound)]
        [HttpGet("{countryId}/currencies")]
        public ActionResult GetCountryCurrencies(int countryId)
        {
            var countryObj = _dbContext.Countries.FirstOrDefault(d => d.Id == countryId);

            if (countryObj == null) return new NotFoundResult();

            var array = _dbContext
                .Countries
                .Where(data => data.Id == countryId)
                .SelectMany(o => o.Currencies)
                .Select(x => new CurrencyUnique(x))
                .ToArray();

            return Ok(array);
        }

        
        /// <summary>
        /// Add Country
        /// </summary>
        /// <param name="countryToCreate">The countryId data to create</param>
        /// <returns>The newly created countryId</returns>
        /// /// <summary>
        /// Creates a Country.
        /// </summary>
        /// <remarks>
        /// Sample request:
        ///
        ///     POST /Countries
        ///     {
        ///        "code": 1,
        ///        "stateName": "United States of America",
        ///        "tld": "us"
        ///     }
        ///
        /// </remarks>
        /// <response code="201">Returns the newly created countryId</response>
        [ProducesResponseType(StatusCodes.Status201Created)]
        [ProducesResponseType(StatusCodes.Status406NotAcceptable)]
        
        [HttpPost]
        public ActionResult AddCountry(CountryCreate countryToCreate)
        {
            Country newCountry = new Country(countryToCreate);
            _dbContext.Countries.Add(newCountry);
            bool success = _dbContext.SaveChanges() >= 0;
            if (!success) return new BadRequestResult();
            return CreatedAtRoute(nameof(GetCountryById), new {countryId = newCountry.Id}, new CountryUnique(newCountry));
        }

        /// <summary>
        /// Updates a Country
        /// </summary>
        /// <param name="countryCode">The countryId ISO 3166 code</param>
        /// <param name="countryToUpdate">Country payload data</param>
        /// <returns></returns>
        [ProducesResponseType(StatusCodes.Status200OK)]
        [ProducesResponseType(StatusCodes.Status400BadRequest)]
        [HttpPut("{countryCode}")]
        public ActionResult UpdateCountry(int countryCode, CountryUpdate countryToUpdate)
        {
            var (success, country) = _dbContext.UpdateCountry(countryToUpdate, countryCode);

            if (success)
            {
                var countryReply = new CountryUnique(country);
                return Ok(countryReply);
            }

            return new NotFoundResult();
        }


        /// <summary>
        /// Adds a currency to Country
        /// </summary>
        /// <param name="countryId"></param>
        /// <param name="currencyCreate"></param>
        /// <returns></returns>
        [ProducesResponseType(StatusCodes.Status200OK)]
        [ProducesResponseType(StatusCodes.Status409Conflict)]
        [HttpPost("{countryId}/currencies")]
        public ActionResult AddCurrency(int countryId, CurrencyCreate currencyCreate)
        {
            var (result, message, country) = _dbContext.AddCurrency(countryId, currencyCreate, 
                new Expression<Func<Currency, bool>>[]
            {
                x => x.Code == currencyCreate.Code,
                y => y.Num == currencyCreate.Num
            });

            if (!result)
            {
                return new ConflictObjectResult(message);
            }
            
            return Ok(new CountryUnique(country));
        }
        
        
    }
}