#requires -version 5.1
<#
.SYNOPSIS
    A PowerShell script with a GUI to merge and deduplicate the contents of hash files.
.DESCRIPTION
    This script provides a user-friendly graphical interface to:
    1. Select multiple text-based hash files.
    2. Read all lines from the selected files.
    3. Remove all duplicate lines efficiently.
    4. Save the merged, unique list of hashes to a new file specified by the user.
.AUTHOR
    Gemini
#>

# Load necessary .NET assemblies for the GUI
Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName System.Drawing

# Suppress errors for a cleaner user experience in the console
$ErrorActionPreference = 'SilentlyContinue'

# --- GUI FORM SETUP ---
$form = New-Object System.Windows.Forms.Form
$form.Text = 'Hash File Merger & Deduplicator'
$form.Size = New-Object System.Drawing.Size(600, 450)
$form.StartPosition = 'CenterScreen'
$form.FormBorderStyle = 'FixedSingle'
$form.MaximizeBox = $false
$form.Icon = [System.Drawing.SystemIcons]::Application

# --- GUI CONTROLS ---

# 1. "Select Files" Button
$selectButton = New-Object System.Windows.Forms.Button
$selectButton.Text = '1. Select Hash Files...'
$selectButton.Location = New-Object System.Drawing.Point(20, 20)
$selectButton.Size = New-Object System.Drawing.Size(550, 40)
$selectButton.Font = New-Object System.Drawing.Font('Segoe UI', 10, [System.Drawing.FontStyle]::Bold)

# 2. ListBox to display selected files
$fileListBox = New-Object System.Windows.Forms.ListBox
$fileListBox.Location = New-Object System.Drawing.Point(20, 70)
$fileListBox.Size = New-Object System.Drawing.Size(550, 200)
$fileListBox.HorizontalScrollbar = $true

# 3. "Merge and Save" Button
$mergeButton = New-Object System.Windows.Forms.Button
$mergeButton.Text = '2. Merge and Save As...'
$mergeButton.Location = New-Object System.Drawing.Point(20, 280)
$mergeButton.Size = New-Object System.Drawing.Size(550, 40)
$mergeButton.Enabled = $false # Disabled until files are selected
$mergeButton.Font = New-Object System.Drawing.Font('Segoe UI', 10, [System.Drawing.FontStyle]::Bold)

# 4. Status Label for feedback
$statusLabel = New-Object System.Windows.Forms.Label
$statusLabel.Text = 'Please select one or more hash files to begin.'
$statusLabel.Location = New-Object System.Drawing.Point(20, 330)
$statusLabel.Size = New-Object System.Drawing.Size(550, 25)
$statusLabel.Font = New-Object System.Drawing.Font('Segoe UI', 9)

# 5. Final Result Label
$resultLabel = New-Object System.Windows.Forms.Label
$resultLabel.Text = ''
$resultLabel.Location = New-Object System.Drawing.Point(20, 355)
$resultLabel.Size = New-Object System.Drawing.Size(550, 25)
$resultLabel.Font = New-Object System.Drawing.Font('Segoe UI', 9, [System.Drawing.FontStyle]::Bold)


# --- EVENT HANDLERS (Button Click Actions) ---

# Action for the "Select Files" button
$selectButton.Add_Click({
    $openFileDialog = New-Object System.Windows.Forms.OpenFileDialog
    $openFileDialog.Title = "Select Hash Files"
    $openFileDialog.Filter = "Text Files (*.txt, *.dic)|*.txt;*.dic|All Files (*.*)|*.*"
    $openFileDialog.Multiselect = $true

    if ($openFileDialog.ShowDialog() -eq 'OK') {
        # Clear previous list and add new files
        $fileListBox.Items.Clear()
        $openFileDialog.FileNames | ForEach-Object { $fileListBox.Items.Add($_) }

        # Update status and enable the merge button
        $statusLabel.Text = "$($fileListBox.Items.Count) file(s) selected."
        $resultLabel.Text = ""
        $mergeButton.Enabled = $true
    }
})

# Action for the "Merge and Save" button
$mergeButton.Add_Click({
    # Disable buttons during processing
    $mergeButton.Enabled = $false
    $selectButton.Enabled = $false
    $form.Cursor = [System.Windows.Forms.Cursors]::WaitCursor

    try {
        $statusLabel.Text = "Processing... Reading files and calculating hashes."
        $form.Refresh() # Force the UI to update

        # Using a HashSet for high-performance deduplication, especially with large files
        $uniqueHashes = [System.Collections.Generic.HashSet[string]]::new([System.StringComparer]::OrdinalIgnoreCase)
        $totalLines = 0

        # Read each file and add its lines to the HashSet
        foreach ($filePath in $fileListBox.Items) {
            $lines = [System.IO.File]::ReadAllLines($filePath)
            $totalLines += $lines.Count
            foreach ($line in $lines) {
                # Only add non-empty lines
                if (-not [string]::IsNullOrWhiteSpace($line)) {
                    $uniqueHashes.Add($line) | Out-Null
                }
            }
        }
        
        $statusLabel.Text = "Read $totalLines total lines. Found $($uniqueHashes.Count) unique lines."
        $resultLabel.Text = "Please choose where to save the merged file."
        $form.Refresh()

        # Prompt user for save location
        $saveFileDialog = New-Object System.Windows.Forms.SaveFileDialog
        $saveFileDialog.Title = "Save Merged Hash File"
        $saveFileDialog.Filter = "Text File (*.txt)|*.txt"
        $saveFileDialog.FileName = "merged_hashes.txt"

        if ($saveFileDialog.ShowDialog() -eq 'OK') {
            # Write the unique hashes to the new file
            [System.IO.File]::WriteAllLines($saveFileDialog.FileName, $uniqueHashes)
            $resultLabel.Text = "Success! Saved $($uniqueHashes.Count) unique hashes to $($saveFileDialog.SafeFileName)."
            $statusLabel.Text = "Process complete. Select more files or close the window."
        } else {
            $resultLabel.Text = "Save operation was cancelled."
        }
    }
    catch {
        [System.Windows.Forms.MessageBox]::Show("An error occurred: $($_.Exception.Message)", "Error", "OK", "Error")
        $resultLabel.Text = "An error occurred during processing."
    }
    finally {
        # Re-enable buttons and restore cursor
        $mergeButton.Enabled = $true
        $selectButton.Enabled = $true
        $form.Cursor = [System.Windows.Forms.Cursors]::Default
    }
})


# --- ADD CONTROLS TO FORM and SHOW ---

$form.Controls.Add($selectButton)
$form.Controls.Add($fileListBox)
$form.Controls.Add($mergeButton)
$form.Controls.Add($statusLabel)
$form.Controls.Add($resultLabel)

# Display the form to the user
[void]$form.ShowDialog()