using System;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Windows.Forms;
using System.Drawing;
using System.Globalization;

public static class ClipboardFusionHelper
{
    private static Form form;
    private static ComboBox caseComboBox;
    private static ComboBox bracketComboBox;
    private static TextBox prefixTextBox;
    private static TextBox suffixTextBox;
    private static CheckBox processEachLineCheckBox;
    private static TextBox previewTextBox;
    private static Label statsLabel;
    private static string originalText;
    private static TextBox findTextBox;
    private static TextBox replaceTextBox;
    private static CheckBox regexCheckBox;
    private static ComboBox actionsComboBox; // New list field for actions

    public static string ProcessText(string text)
    {
        if (string.IsNullOrEmpty(text))
            return text;

        originalText = text;
        ShowForm();
        return originalText;
    }

    private static void ShowForm()
    {
        form = new Form
        {
            Text = "Text Processing",
            Size = new Size(800, 400),
            MinimumSize = new Size(600, 350),
            FormBorderStyle = FormBorderStyle.Sizable,
            StartPosition = FormStartPosition.CenterScreen
        };

        // Creating control elements
        Label caseLabel = new Label
        {
            Text = "Change case:",
            AutoSize = true,
            Location = new Point(10, 12)
        };

        caseComboBox = new ComboBox
        {
            DropDownStyle = ComboBoxStyle.DropDownList,
            Location = new Point(10, 32),
            Width = 200
        };
        caseComboBox.Items.AddRange(new object[]
        {
            "No change",
            "Title Case",
            "ALL UPPERCASE",
            "all lowercase",
            "Sentence case"
        });
        caseComboBox.SelectedIndex = 0;
        caseComboBox.SelectedIndexChanged += (s, e) => UpdatePreview();

        Label bracketLabel = new Label
        {
            Text = "Text enclosure:",
            AutoSize = true,
            Location = new Point(220, 12)
        };

        bracketComboBox = new ComboBox
        {
            DropDownStyle = ComboBoxStyle.DropDownList,
            Location = new Point(220, 32),
            Width = 200
        };
        bracketComboBox.Items.AddRange(new object[]
        {
            "No enclosure",
            "In quotes",
            "In guillemets",
            "In parentheses",
            "In square brackets",
            "Custom"
        });
        bracketComboBox.SelectedIndex = 0;
        bracketComboBox.SelectedIndexChanged += (s, e) =>
        {
            bool isCustom = bracketComboBox.SelectedIndex == 5;
            prefixTextBox.Visible = isCustom;
            suffixTextBox.Visible = isCustom;
            UpdatePreview();
        };

        prefixTextBox = new TextBox
        {
            Location = new Point(430, 32),
            Width = 50,
            Visible = false
        };
        prefixTextBox.TextChanged += (s, e) => UpdatePreview();

        suffixTextBox = new TextBox
        {
            Location = new Point(490, 32),
            Width = 50,
            Visible = false
        };
        suffixTextBox.TextChanged += (s, e) => UpdatePreview();

        processEachLineCheckBox = new CheckBox
        {
            Text = "Process each line",
            AutoSize = true,
            Location = new Point(220, 62)
        };
        processEachLineCheckBox.CheckedChanged += (s, e) => UpdatePreview();

        // "Find and Replace" group
        GroupBox findReplaceGroup = new GroupBox
        {
            Text = "Find and Replace",
            Location = new Point(10, 80), // Moved down below processEachLineCheckBox
            Size = new Size(760, 100),
            Anchor = AnchorStyles.Top | AnchorStyles.Left
        };

        Label findLabel = new Label
        {
            Text = "Find:",
            AutoSize = true,
            Location = new Point(10, 20)
        };

        findTextBox = new TextBox
        {
            Location = new Point(10, 40),
            Width = 180
        };
        findTextBox.TextChanged += (s, e) =>
        {
            if (!regexCheckBox.Checked || !string.IsNullOrEmpty(replaceTextBox.Text))
                UpdatePreview();
        };

        Label replaceLabel = new Label
        {
            Text = "Replace:",
            AutoSize = true,
            Location = new Point(220, 20) // Located to the right of the "Find" field
        };

        replaceTextBox = new TextBox
        {
            Location = new Point(220, 40), // Located to the right of the "Find" field
            Width = 180
        };
        replaceTextBox.TextChanged += (s, e) =>
        {
            if (!regexCheckBox.Checked || !string.IsNullOrEmpty(findTextBox.Text))
                UpdatePreview();
        };

        // Adding a new list field "Actions"
        Label actionsLabel = new Label
        {
            Text = "Actions:",
            AutoSize = true,
            Location = new Point(430, 20) // Located to the right of the "Replace" field
        };

        actionsComboBox = new ComboBox
        {
            DropDownStyle = ComboBoxStyle.DropDownList,
            Location = new Point(430, 40), // Located to the right of the "Replace" field
            Width = 280
        };
        actionsComboBox.Items.AddRange(new object[]
        {
            "No action",
            "Remove leading spaces and tabs",
            "Remove trailing spaces and tabs",
            "Remove leading and trailing spaces and tabs"
        });
        actionsComboBox.SelectedIndex = 0;
        actionsComboBox.SelectedIndexChanged += (s, e) => UpdatePreview();

        regexCheckBox = new CheckBox
        {
            Text = "Regular expressions",
            AutoSize = true,
            Location = new Point(10, 70) // Under the "Find" field
        };
        regexCheckBox.CheckedChanged += (s, e) => UpdatePreview();

        // Adding elements to the group
        findReplaceGroup.Controls.AddRange(new Control[]
        {
            findLabel, findTextBox, replaceLabel, replaceTextBox,
            actionsLabel, actionsComboBox, regexCheckBox
        });

        previewTextBox = new TextBox
        {
            Multiline = true,
            ScrollBars = ScrollBars.Vertical,
            Location = new Point(10, 190), // Changed position considering the new group
            Width = form.ClientSize.Width - 20,
            Height = form.ClientSize.Height - 255,
            Anchor = AnchorStyles.Top | AnchorStyles.Left | AnchorStyles.Right | AnchorStyles.Bottom
        };

        statsLabel = new Label
        {
            AutoSize = true,
            Location = new Point(10, form.ClientSize.Height - 60),
            Anchor = AnchorStyles.Left | AnchorStyles.Bottom
        };

        Button okButton = new Button
        {
            Text = "OK",
            Location = new Point(form.ClientSize.Width - 180, form.ClientSize.Height - 40),
            Width = 80,
            Anchor = AnchorStyles.Right | AnchorStyles.Bottom
        };
        okButton.Click += (s, e) =>
        {
            originalText = previewTextBox.Text;
            form.DialogResult = DialogResult.OK;
            form.Close();
        };

        Button cancelButton = new Button
        {
            Text = "Cancel",
            Location = new Point(form.ClientSize.Width - 90, form.ClientSize.Height - 40),
            Width = 80,
            Anchor = AnchorStyles.Right | AnchorStyles.Bottom
        };
        cancelButton.Click += (s, e) =>
        {
            form.DialogResult = DialogResult.Cancel;
            form.Close();
        };

        // Adding elements to the form
        form.Controls.AddRange(new Control[]
        {
            caseLabel, caseComboBox,
            bracketLabel, bracketComboBox,
            prefixTextBox, suffixTextBox,
            processEachLineCheckBox,
            findReplaceGroup,
            previewTextBox, statsLabel,
            okButton, cancelButton
        });

        // Initializing preview
        previewTextBox.Text = originalText;
        UpdateStats();

        form.ShowDialog();
    }

    private static void UpdatePreview()
    {
        string processedText = originalText;

        // Processing text based on selected options
        if (processEachLineCheckBox.Checked)
        {
            string[] lines = processedText.Split(new []
            {
                "\r\n", "\r", "\n"
            }, StringSplitOptions.None);
            for (int i = 0; i < lines.Length; i++)
            {
                lines[i] = ProcessCase(lines[i]);
                lines[i] = ProcessFindReplace(lines[i]);
                lines[i] = ProcessActions(lines[i]); // Adding action processing
                lines[i] = ProcessBrackets(lines[i]);
            }
            processedText = string.Join(Environment.NewLine, lines);
        }
        else
        {
            processedText = ProcessCase(processedText);
            processedText = ProcessFindReplace(processedText);
            processedText = ProcessActions(processedText); // Adding action processing
            processedText = ProcessBrackets(processedText);
        }

        previewTextBox.Text = processedText;
        UpdateStats();
    }

    private static string ProcessCase(string text)
    {
        switch (caseComboBox.SelectedIndex)
        {
            case 1: // Title Case
                TextInfo textInfo = new CultureInfo("en-US", false).TextInfo;
                return textInfo.ToTitleCase(text.ToLower());

            case 2: // ALL UPPERCASE
                return text.ToUpper();

            case 3: // all lowercase
                return text.ToLower();

            case 4: // Sentence case
                if (string.IsNullOrEmpty(text)) return text;

                // Splitting text into sentences
                string[] sentences = Regex.Split(text, @"(?<=[.!?])\s+");
                for (int i = 0; i < sentences.Length; i++)
                {
                    if (!string.IsNullOrEmpty(sentences[i]))
                    {
                        // Capitalizing the first letter of the sentence
                        sentences[i] = char.ToUpper(sentences[i][0]) +
                                     (sentences[i].Length > 1 ? sentences[i].Substring(1).ToLower() : "");
                    }
                }
                return string.Join(" ", sentences);

            default: // No change
                return text;
        }
    }

    private static string ProcessFindReplace(string text)
    {
        if (string.IsNullOrEmpty(findTextBox.Text))
            return text;

        try
        {
            if (regexCheckBox.Checked)
            {
                // Checking if both fields are filled when using regular expressions
                if (string.IsNullOrEmpty(replaceTextBox.Text))
                    return text; // Returning original text if replace field is empty

                // Using regular expressions for find and replace
                return Regex.Replace(text, findTextBox.Text, replaceTextBox.Text ?? "");
            }
            else
            {
                // Regular find and replace
                return text.Replace(findTextBox.Text, replaceTextBox.Text ?? "");
            }
        }
        catch (Exception ex)
        {
            // In case of an error in regular expression, return the original text
            MessageBox.Show($"Expression error: {ex.Message}", "Error",
                        MessageBoxButtons.OK, MessageBoxIcon.Error);
            return text;
        }
    }

    // New method for processing actions
    private static string ProcessActions(string text)
    {
        switch (actionsComboBox.SelectedIndex)
        {
            case 1: // Remove leading spaces and tabs
                return text.TrimStart();

            case 2: // Remove trailing spaces and tabs
                return text.TrimEnd();

            case 3: // Remove leading and trailing spaces and tabs
                return text.Trim();

            default: // No action
                return text;
        }
    }

    private static string ProcessBrackets(string text)
    {
        switch (bracketComboBox.SelectedIndex)
        {
            case 1: // In quotes
                return "\"" + text + "\"";

            case 2: // In guillemets
                return "«" + text + "»";

            case 3: // In parentheses
                return "(" + text + ")";

            case 4: // In square brackets
                return "[" + text + "]";

            case 5: // Custom
                return prefixTextBox.Text + text + suffixTextBox.Text;

            default: // No enclosure
                return text;
        }
    }

    private static void UpdateStats()
    {
        string text = previewTextBox.Text;
        int charCount = text.Length;
        int wordCount = string.IsNullOrWhiteSpace(text) ? 0 :
        Regex.Matches(text, @"\b\w+\b").Count;
        int lineCount = string.IsNullOrWhiteSpace(text) ? 0 :
        text.Split(new []
        {
            "\r\n", "\r", "\n"
        }, StringSplitOptions.None).Length;

        statsLabel.Text = $"Statistics: {wordCount} words, {charCount} characters, {lineCount} lines";
    }
}