// ***********************************************************************
// Assembly         : Ultimate
// Author           : frede
// Created          : 2023 06 11 15:57
// 
// Last Modified By : frede
// Last Modified On : 2023 06 11 15:57
// ***********************************************************************
// <copyright file="CsvOutputFormatter.cs" company="FCS">
//     Copyright (C) 2023-2023 FCS Frede's Computer Services.
//     This program is free software: you can redistribute it and/or modify
//     it under the terms of the GNU Affero General Public License as
//     published by the Free Software Foundation, either version 3 of the
//     License, or (at your option) any later version.
// 
//     This program is distributed in the hope that it will be useful,
//     but WITHOUT ANY WARRANTY; without even the implied warranty of
//     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//     GNU Affero General Public License for more details.
// 
//     You should have received a copy of the GNU Affero General Public License
//     along with this program.  If not, see [https://www.gnu.org/licenses]
// </copyright>
// <summary></summary>
// ***********************************************************************

using System.Text;
using Microsoft.AspNetCore.Mvc.Formatters;
using Microsoft.Net.Http.Headers;
using Shared.DataTransferObjects;

namespace Ultimate;

public class CsvOutputFormatter : TextOutputFormatter
{
    public CsvOutputFormatter()
    {
        SupportedMediaTypes.Add(MediaTypeHeaderValue.Parse("text/csv"));
        SupportedEncodings.Add(Encoding.UTF8);
        SupportedEncodings.Add(Encoding.Unicode);
    }

    protected override bool CanWriteType(Type? type)
    {
        if (typeof(CompanyDto).IsAssignableFrom(type) || typeof(IEnumerable<CompanyDto>).IsAssignableFrom(type))
        {
            return base.CanWriteType(type);
        }

        return false;
    }

    public override async Task WriteResponseBodyAsync(OutputFormatterWriteContext context, Encoding selectedEncoding)
    {
        var response = context.HttpContext.Response;
        var buffer = new StringBuilder();
        if (context.Object is IEnumerable<CompanyDto>)
        {
            foreach (var company in (IEnumerable<CompanyDto>) context.Object)
            {
                FormatCsv(buffer, company);
            }
        }
        else
        {
            FormatCsv(buffer, (CompanyDto) context.Object);
        }
        await response.WriteAsync(buffer.ToString());
    }

    private static void FormatCsv(StringBuilder buffer, CompanyDto company)
    {
        buffer.AppendLine($"{company.CompanyId},\"{company.Name}\",\"{company.FullAddress}\"");
    }
}