using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;

namespace Lab2 {
    public partial class Form1 : Form {
        enum AllStates { Recognized = 0, Good = 1, BadSymbol = 2, EmptyCellRecognized = 3, EmptyCellGood = 4 };
        string[] statusString;
        Dictionary<string, Dictionary<string, string>> lang;
        List<string> states;
        List<string> terminal;
        List<string> endStates;
        public Form1() {
            lang = new Dictionary<string, Dictionary<string, string>>();
            states = new List<string>();
            terminal = new List<string>();
            endStates = new List<string>();
            statusString = new string[5] { "Цепочка принадлежит", "Цепочка не пренадлежит", "Неверный Символ", "Нет перехода, цепочка принадлежит", "Нет перехода, цепочка не принадлежит" };
            InitializeComponent();
            textBox_input.ReadOnly = false;
            //dataGridView.RowHeadersWidth = 50;
        }

        private void ShowError(string error) => MessageBox.Show(error, "Ошибка!", MessageBoxButtons.OK, MessageBoxIcon.Error);

        private void button_add_row_Click(object sender, EventArgs e) {
            if (dataGridView.ColumnCount == 0) {
                ShowError("Сначала добавьте как минимум один столбец!");
                return;
            }
            string input;
            InputForm inputForm = new InputForm();
            inputForm.label.Text += " состояния";
            if (inputForm.ShowDialog(this) == DialogResult.OK) {
                input = inputForm.textBox_input.Text;
            } else return;
            inputForm.Dispose();

            if (input.Length == 0) {
                ShowError("Пожалуйста, заполните поле!");
                return;
            }
            if (states.Contains(input)) {
                ShowError("Такое состояние уже определено!");
                return;
            } else {
                states.Add(input);
                //if (!((dataGridView.RowCount == 1) && (dataGridView.Rows[0].HeaderCell.Value == string.Empty)))
                dataGridView.Rows.Add();
                dataGridView.Rows[dataGridView.RowCount - 1].HeaderCell.Value = input;
            }
        }

        bool FormDictionary() {
            return true;
        }

        private void button_add_column_Click(object sender, EventArgs e) {
            string input;
            InputForm inputForm = new InputForm();
            inputForm.label.Text += " символа";
            inputForm.textBox_input.MaxLength = 1;
            if (inputForm.ShowDialog(this) == DialogResult.OK) {
                input = inputForm.textBox_input.Text;
            } else return;
            inputForm.Dispose();

            if (input.Length == 0) {
                ShowError("Пожалуйста, заполните поле!");
                return;
            }
            if (terminal.Contains(input)) {
                ShowError("Такой символ уже определено!");
                return;
            } else {
                terminal.Add(input);
                dataGridView.Columns.Add(input, input);
                if (dataGridView.RowCount == 1)
                    dataGridView.Rows[dataGridView.RowCount - 1].HeaderCell.Value = string.Empty;
            }
        }

        private void button_make_table_Click(object sender, EventArgs e) {
            if (textBox_states.Text == String.Empty || textBox_terminal.Text == String.Empty)
                return;
            if (dataGridView.Columns.Count > 0) {
                dataGridView.Rows.Clear();
                dataGridView.Columns.Clear();
                dataGridView.Refresh();
            }
            if (terminal.Count > 0)
                terminal.Clear();
            if (states.Count > 0)
                states.Clear();

            terminal = textBox_terminal.Text.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries).ToList();
            if (terminal.Count > 0)
                terminal = terminal.Select(str => str.Trim()).Distinct().ToList();
            if (terminal.Any(x => x.Length != 1)) {
                ShowError("Один из символов алфавита является строкой!");
                return;
            }

            states = textBox_states.Text.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries).ToList();
            states = states.Select(s => s.Trim()).Distinct().ToList();

            if (states.Count == 0 || terminal.Count == 0) {
                ShowError("Поля заполнены неверно!");
                return;
            }

            foreach (string str1 in terminal)
                if (states.Contains(str1)) {
                    ShowError("Один из символов алфавита также задан состоянием: " + str1);
                    return;
                }

            for (int i = 0; i < terminal.Count(); ++i)
                dataGridView.Columns.Add(terminal[i].ToString(), terminal[i].ToString());
            for (int i = 0; i < states.Count(); ++i)
                dataGridView.Rows.Add();
            for (int i = 0; i < states.Count(); ++i)
                dataGridView.Rows[i].HeaderCell.Value = states[i];

            if (comboBox_start.Items.Count > 0)
                comboBox_start.Items.Clear();
            foreach (string str in states)
                comboBox_start.Items.Add(str);
            comboBox_start.SelectedIndex = 0;
        }

        private void dataGridView_CellValueChanged(object sender, DataGridViewCellEventArgs e) {
            if (lang.Count > 0)
                lang.Clear();
        }

        bool CheckTable() {
            for (int i = 0; i < dataGridView.RowCount; ++i)
                for (int j = 0; j < dataGridView.ColumnCount; ++j)
                    if (dataGridView.Rows[i].Cells[j].Value.ToString() != string.Empty && !states.Contains(dataGridView.Rows[i].Cells[j].Value.ToString()))
                        return false;
            return true;
        }

        bool BuildLanguage() {
            for (int i = 0; i < dataGridView.RowCount; ++i)
                for (int j = 0; j < dataGridView.ColumnCount; ++j)
                    if (dataGridView.Rows[i].Cells[j].Value == null)
                        dataGridView.Rows[i].Cells[j].Value = string.Empty;
            if (!CheckTable())
                return false;
            if (lang.Count > 0)
                lang.Clear();
            for (int i = 0; i < dataGridView.RowCount; ++i) {
                lang.Add(dataGridView.Rows[i].HeaderCell.Value.ToString(), new Dictionary<string, string>());
                for (int j = 0; j < dataGridView.ColumnCount; ++j) {
                    lang[dataGridView.Rows[i].HeaderCell.Value.ToString()].Add(dataGridView.Columns[j].HeaderCell.Value.ToString(), dataGridView.Rows[i].Cells[j].Value.ToString());
                }
            }
            return true;
        }

        void ChangeStatus(AllStates status) {
            label_status.Text = statusString[(int)status];
        }

        private void textBox_input_TextChanged(object sender, EventArgs e) {
            if (lang.Count() == 0)
                if (!BuildLanguage())
                    return;
            string lastState = comboBox_start.SelectedItem.ToString();
            if (textBox_input.Text == String.Empty) {
                if (endStates.Contains(lastState))
                    ChangeStatus(AllStates.Recognized);
                else
                    ChangeStatus(AllStates.Good);
                textBox_states_order.Text = "(" + lastState + ", " + ")";
                return;
            }
            if (textBox_states_order.Text.Length > 0)
                textBox_states_order.Text = string.Empty;
            for (int i = 0; i < textBox_input.Text.Length; ++i) {
                string lastInput = textBox_input.Text[i].ToString();
                if (!terminal.Contains(lastInput)) {
                    ChangeStatus(AllStates.BadSymbol);
                    textBox_states_order.Text += "(" + lastState + ", " + textBox_input.Text.Substring(i) + ")";
                    return;
                }
                textBox_states_order.Text += "(" + lastState + ", " + textBox_input.Text.Substring(i) + ")" + " --> ";
                lastState = lang[lastState][lastInput];
                if (lastState == string.Empty) {
                    if (label_status.Text == statusString[(int)AllStates.Good])
                        ChangeStatus(AllStates.EmptyCellGood);
                    else
                        ChangeStatus(AllStates.EmptyCellRecognized);
                    return;
                }
                if (endStates.Contains(lastState))
                    ChangeStatus(AllStates.Recognized);
                else
                    ChangeStatus(AllStates.Good);
            }
            textBox_states_order.Text += "(" + lastState + ", " + ")" ;
        }

        private void textBox_end_TextChanged(object sender, EventArgs e) {
            if (endStates.Count > 0)
                endStates.Clear();
            endStates = textBox_end.Text.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries).ToList();
            endStates = endStates.Select(s => s.Trim()).Distinct().ToList();
            if (endStates.Count == 0) {
                textBox_input.ReadOnly = true;
                return;
            }
            foreach (string str in endStates)
                if (!states.Contains(str)) {
                    textBox_input.ReadOnly = true;
                    return;
                }
            textBox_input.ReadOnly = false;
        }

        private void comboBox_start_SelectedIndexChanged(object sender, EventArgs e) {
            if (lang.Count > 0)
                lang.Clear();
        }
    }
}