// download - the admin console and reports
// Copyright (C) 2024 Ian Cowburn <ianc@noddybox.co.uk>
// 
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU 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 General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Npgsql;
using System.Collections.Generic;
using download_admin;
using Microsoft.AspNetCore.Http.HttpResults;
using System.Text;
using System.Text.Encodings;

namespace download_admin.Pages;

public class ReportModel : PageModel
{
    public void OnGet()
    {
        ViewData["Title"] = "Download Repsoitory Report";
        GetData();
    }

    public IActionResult OnPost()
    {
        GetData();

        StringBuilder str = new StringBuilder();

        foreach (var row in Rows)
        {
            str.AppendFormat("{0},{1}", row.Time.ToString("o", System.Globalization.CultureInfo.InvariantCulture), row.Key);
            foreach (var s in row.Info)
            {
                str.AppendFormat(",{0}", s);
            }
            str.AppendLine();
        }

        byte[] file_data = UTF8Encoding.UTF8.GetBytes(str.ToString());
        
        return File(file_data, "text/csv","downloads.csv");
    }

    private void GetData()
    {
        try
        {
            Rows = new List<Download>();

            using var conn = new NpgsqlConnection(Config.Settings["ConnectionStrings:download"]);

            conn.Open();

            using var cmd = new NpgsqlCommand("SELECT key, info, time FROM download ORDER BY time", conn);
            using var reader = cmd.ExecuteReader();
            
            while(reader.Read())
            {
                string key = (string)reader["key"];
                string[] info = (string[])reader["info"];
                DateTime time = (DateTime)reader["time"];

                Rows.Add(new Download(key, info, time));
            }
        }
        catch(Exception e)
        {
            SetError(e.Message);
        }
    }

    private void SetError(string error_text)
    {
        HasError = true;
        ErrorText = error_text;
    }

    public List<string> Keys
    {
        get
        {
            var keys = new List<String>();

            try
            {
                using var conn = new NpgsqlConnection(Config.Settings["ConnectionStrings:download"]);

                conn.Open();

                using var cmd = new NpgsqlCommand("SELECT key FROM file_object ORDER BY key", conn);
                using var reader = cmd.ExecuteReader();
                
                while(reader.Read())
                {
                    string key = (string)reader["key"];
                    keys.Add(key);
                }
            }
            catch(Exception e)
            {
                SetError(e.Message);
            }

            return keys;
        }

    }

    public long GetCount(string key)
    {
        try
        {
            using var conn = new NpgsqlConnection(Config.Settings["ConnectionStrings:download"]);

            conn.Open();

            using var cmd = new NpgsqlCommand("SELECT count(*) FROM download where key = @key", conn);
            cmd.Parameters.AddWithValue("key", NpgsqlTypes.NpgsqlDbType.Varchar, key);

            object? scalar = cmd.ExecuteScalar();

            if (scalar != null)
            {
                return (long)scalar;
            }
        }
        catch(Exception e)
        {
            SetError(e.Message);
        }

        return 0;
    }

    public List<Download>? Rows {get;private set;}

    public bool HasError {get; private set;}

    public string? ErrorText {get; private set;}

}