using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Windows.Forms;

namespace ConfigEditor
{
    public partial class MainForm: Form
    {
        private string opened_file_path = null;
        private string[] original_file_data = null;

        public MainForm()
        {
            InitializeComponent();
        }

        private void ClearData()
        {
            opened_file_path = null;
            if (original_file_data != null)
                Array.Clear(original_file_data, 0, original_file_data.Length);
            richTextBox1.Clear();
            ActiveForm.Text = "SaveWizard Config Editor";
        }

        private void openToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (!IsModificationSaved())
                return;
            ClearData();
            OpenFileDialog ofd = new OpenFileDialog()
            {
                Title = "Choose configuration file",
                Filter = "File *.json|*.json",
                Multiselect = false
            };
            if (ofd.ShowDialog() == DialogResult.OK)
            {
                opened_file_path = ofd.FileName;
                original_file_data = File.ReadAllLines(ofd.FileName);
                richTextBox1.Text = File.ReadAllText(ofd.FileName);
                ActiveForm.Text = $"{ofd.FileName} - SaveWizard Config Editor";
            }
        }

        private void saveToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (opened_file_path == null)
                return;
            File.WriteAllText(opened_file_path, richTextBox1.Text);
        }

        private void saveAsToolStripMenuItem_Click(object sender, EventArgs e)
        {
            SaveFileDialog sfd = new SaveFileDialog
            {
                Title = "Save configuration file",
                Filter = "File *.json|*.json"
            };
            if (sfd.ShowDialog() == DialogResult.OK)
            {
                File.WriteAllText(sfd.FileName, richTextBox1.Text);
                opened_file_path = sfd.FileName;
                ActiveForm.Text = $"{sfd.FileName} - SaveWizard Config Editor";
            }
        }

        private void generateMD5ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            using (var md5 = MD5.Create())
            {
                using (FileStream stream = File.OpenRead(opened_file_path))
                    md5.ComputeHash(stream);
                
                StringBuilder sb = new StringBuilder();
                byte[] hash = md5.Hash;
                for (int i = 0; i < hash.Length; i++)
                    sb.Append(hash[i].ToString("x2"));

                Clipboard.SetText(sb.ToString());
                MessageBox.Show($"Hash successfully copied into your clipboard.", "Success", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
        }

        private bool IsModificationSaved()
        {
            if (opened_file_path == null)
                return true;
            bool isDataEquals = true;
            string[] rtbLines = richTextBox1.Text.Split(
                new[] { "\r\n", "\r", "\n" },
                StringSplitOptions.None
            );
            for (int i = 0; i < original_file_data.Length; i++)
            {
                if (rtbLines[i] != original_file_data[i])
                {
                    isDataEquals = false;
                    break;
                }
            }
            if (isDataEquals)
            {
                return true;
            }
            DialogResult result = MessageBox.Show("The document has been modified.\nDo you want to save your changes?", "Question", MessageBoxButtons.YesNoCancel, MessageBoxIcon.Question);
            if (result == DialogResult.Yes)
            {
                File.WriteAllText(opened_file_path, richTextBox1.Text);
                MessageBox.Show("File successfully saved.", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
                return true;
            } else if (result == DialogResult.No)
                return true;
            else if (result == DialogResult.Cancel)
                return false;
            return false;
        }

        private void closeFileToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (!IsModificationSaved())
                return;
            ClearData();
        }

        private void closeToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (!IsModificationSaved())
                return;
            Application.Exit();
        }

        private void MainForm_FormClosed(object sender, FormClosedEventArgs e)
        {
            if (!IsModificationSaved())
                return;
            Application.Exit();
        }
    }
}