<#
==============================================================================
 Azure DevOps to GitHub Migration - Automated Setup Script
==============================================================================
 Author: Swarup Puvvada
 Description: Automates the entire ADO to GitHub migration process with
              GUI-based input collection for all required variables.
 Version: 2.1
 Date: January 23, 2026
 
 Features:
 - GUI popup windows for variable collection
 - Option to migrate single repo or all repos
 - Automated gh CLI extension installation
 - PAT validation and testing
 - Comprehensive error handling
 - Detailed logging
 - Progress tracking
 
 Created by: Swarup Puvvada
 GitHub: https://github.com/ado2gh-swarup
==============================================================================
#>

# Set error action preference
$ErrorActionPreference = "Stop"

# Create log file
$LogFile = "ADO-GitHub-Migration-$(Get-Date -Format 'yyyyMMdd-HHmmss').log"

function Write-Log {
    param([string]$Message, [string]$Level = "INFO")
    $timestamp = Get-Date -Format "yyyy-MM-dd HH:mm:ss"
    $logMessage = "[$timestamp] [$Level] $Message"
    Write-Host $logMessage
    Add-Content -Path $LogFile -Value $logMessage
}

function Show-InputDialog {
    param(
        [string]$Title,
        [string]$Prompt,
        [bool]$IsPassword = $false
    )
    
    Add-Type -AssemblyName System.Windows.Forms
    Add-Type -AssemblyName System.Drawing

    $form = New-Object System.Windows.Forms.Form
    $form.Text = $Title
    $form.Size = New-Object System.Drawing.Size(500, 200)
    $form.StartPosition = 'CenterScreen'
    $form.FormBorderStyle = 'FixedDialog'
    $form.MaximizeBox = $false
    $form.MinimizeBox = $false

    $label = New-Object System.Windows.Forms.Label
    $label.Location = New-Object System.Drawing.Point(10, 20)
    $label.Size = New-Object System.Drawing.Size(460, 40)
    $label.Text = $Prompt
    $form.Controls.Add($label)

    $textBox = New-Object System.Windows.Forms.TextBox
    $textBox.Location = New-Object System.Drawing.Point(10, 70)
    $textBox.Size = New-Object System.Drawing.Size(460, 20)
    if ($IsPassword) {
        $textBox.UseSystemPasswordChar = $true
    }
    $form.Controls.Add($textBox)

    $okButton = New-Object System.Windows.Forms.Button
    $okButton.Location = New-Object System.Drawing.Point(300, 110)
    $okButton.Size = New-Object System.Drawing.Size(75, 30)
    $okButton.Text = 'OK'
    $okButton.DialogResult = [System.Windows.Forms.DialogResult]::OK
    $form.AcceptButton = $okButton
    $form.Controls.Add($okButton)

    $cancelButton = New-Object System.Windows.Forms.Button
    $cancelButton.Location = New-Object System.Drawing.Point(390, 110)
    $cancelButton.Size = New-Object System.Drawing.Size(75, 30)
    $cancelButton.Text = 'Cancel'
    $cancelButton.DialogResult = [System.Windows.Forms.DialogResult]::Cancel
    $form.CancelButton = $cancelButton
    $form.Controls.Add($cancelButton)

    $result = $form.ShowDialog()

    if ($result -eq [System.Windows.Forms.DialogResult]::OK) {
        return $textBox.Text
    }
    else {
        return $null
    }
}

function Show-MessageBox {
    param([string]$Message, [string]$Title = "Information")
    Add-Type -AssemblyName System.Windows.Forms
    [System.Windows.Forms.MessageBox]::Show($Message, $Title, 'OK', 'Information')
}

function Show-ChoiceDialog {
    param(
        [string]$Title,
        [string]$Prompt,
        [string[]]$Choices
    )
    
    Add-Type -AssemblyName System.Windows.Forms
    Add-Type -AssemblyName System.Drawing

    $form = New-Object System.Windows.Forms.Form
    $form.Text = $Title
    $form.Size = New-Object System.Drawing.Size(500, 250)
    $form.StartPosition = 'CenterScreen'
    $form.FormBorderStyle = 'FixedDialog'
    $form.MaximizeBox = $false
    $form.MinimizeBox = $false

    $label = New-Object System.Windows.Forms.Label
    $label.Location = New-Object System.Drawing.Point(10, 20)
    $label.Size = New-Object System.Drawing.Size(460, 40)
    $label.Text = $Prompt
    $form.Controls.Add($label)

    $radioButtons = @()
    $yPosition = 70
    for ($i = 0; $i -lt $Choices.Length; $i++) {
        $radioButton = New-Object System.Windows.Forms.RadioButton
        $radioButton.Location = New-Object System.Drawing.Point(20, $yPosition)
        $radioButton.Size = New-Object System.Drawing.Size(450, 30)
        $radioButton.Text = $Choices[$i]
        if ($i -eq 0) { $radioButton.Checked = $true }
        $form.Controls.Add($radioButton)
        $radioButtons += $radioButton
        $yPosition += 35
    }

    $buttonY = $yPosition + 10
    $okButton = New-Object System.Windows.Forms.Button
    $okButton.Location = New-Object System.Drawing.Point(300, $buttonY)
    $okButton.Size = New-Object System.Drawing.Size(75, 30)
    $okButton.Text = 'OK'
    $okButton.DialogResult = [System.Windows.Forms.DialogResult]::OK
    $form.AcceptButton = $okButton
    $form.Controls.Add($okButton)

    $cancelButton = New-Object System.Windows.Forms.Button
    $cancelButton.Location = New-Object System.Drawing.Point(390, $buttonY)
    $cancelButton.Size = New-Object System.Drawing.Size(75, 30)
    $cancelButton.Text = 'Cancel'
    $cancelButton.DialogResult = [System.Windows.Forms.DialogResult]::Cancel
    $form.CancelButton = $cancelButton
    $form.Controls.Add($cancelButton)

    $result = $form.ShowDialog()

    if ($result -eq [System.Windows.Forms.DialogResult]::OK) {
        for ($i = 0; $i -lt $radioButtons.Length; $i++) {
            if ($radioButtons[$i].Checked) {
                return $i
            }
        }
    }
    return -1
}

# Main Script Execution
Write-Log "========================================" "INFO"
Write-Log "ADO to GitHub Migration Script Started" "INFO"
Write-Log "Author: Swarup Puvvada" "INFO"
Write-Log "========================================" "INFO"

# Welcome Message
Show-MessageBox -Title "Welcome!" -Message "Welcome to Azure DevOps to GitHub Migration Tool!`n`nThis wizard will guide you through the migration process.`n`nCreated by: Swarup Puvvada`nGitHub: https://github.com/ado2gh-swarup"

# Ask migration type
Write-Log "Asking user for migration type..." "INFO"
$migrationChoice = Show-ChoiceDialog -Title "Migration Type" -Prompt "Choose your migration type:" -Choices @(
    "Migrate a SINGLE repository",
    "Migrate ALL repositories from ONE Team Project",
    "Migrate ALL repositories from ALL Team Projects (entire organization)"
)

if ($migrationChoice -eq -1) { 
    Write-Log "User cancelled." "ERROR"
    exit 
}

$migrateSingle = ($migrationChoice -eq 0)
$migrateOneProject = ($migrationChoice -eq 1)
$migrateAllProjects = ($migrationChoice -eq 2)

if ($migrateSingle) {
    Write-Log "Migration type selected: SINGLE repository" "INFO"
} elseif ($migrateOneProject) {
    Write-Log "Migration type selected: ALL repositories from ONE Team Project" "INFO"
} else {
    Write-Log "Migration type selected: ALL repositories from ALL Team Projects" "INFO"
}

# Collect Azure DevOps Information
Write-Log "Collecting Azure DevOps information..." "INFO"
$AdoOrg = Show-InputDialog -Title "Azure DevOps Organization" -Prompt "Enter your Azure DevOps Organization name:"
if (-not $AdoOrg) { Write-Log "User cancelled." "ERROR"; exit }

if ($migrateSingle) {
    # For single repo migration
    $AdoTeamProject = Show-InputDialog -Title "Azure DevOps Team Project" -Prompt "Enter your Azure DevOps Team Project name:"
    if (-not $AdoTeamProject) { Write-Log "User cancelled." "ERROR"; exit }

    $AdoRepo = Show-InputDialog -Title "Azure DevOps Repository" -Prompt "Enter your Azure DevOps Repository name:"
    if (-not $AdoRepo) { Write-Log "User cancelled." "ERROR"; exit }
} elseif ($migrateOneProject) {
    # For migrating all repos from ONE team project
    $AdoTeamProject = Show-InputDialog -Title "Azure DevOps Team Project" -Prompt "Enter the Team Project name (all repos from this project will be migrated):"
    if (-not $AdoTeamProject) { Write-Log "User cancelled." "ERROR"; exit }
    
    $AdoRepo = $null
} else {
    # For migrating all repos from ALL team projects
    $AdoTeamProject = $null
    $AdoRepo = $null
    Show-MessageBox -Title "Info" -Message "The script will discover and migrate ALL repositories from ALL Team Projects in your organization: $AdoOrg`n`nThis may take a long time!"
}

$AdoPat = Show-InputDialog -Title "Azure DevOps PAT" -Prompt "Enter your Azure DevOps Personal Access Token (PAT):" -IsPassword $true
if (-not $AdoPat) { Write-Log "User cancelled." "ERROR"; exit }

# Collect GitHub Information
Write-Log "Collecting GitHub information..." "INFO"
$GhOrg = Show-InputDialog -Title "GitHub Organization" -Prompt "Enter your GitHub Organization name:"
if (-not $GhOrg) { Write-Log "User cancelled." "ERROR"; exit }

if ($migrateSingle) {
    $GhRepo = Show-InputDialog -Title "GitHub Repository" -Prompt "Enter your GitHub Repository name:"
    if (-not $GhRepo) { Write-Log "User cancelled." "ERROR"; exit }
} else {
    $GhRepo = $null
}

$GhPat = Show-InputDialog -Title "GitHub PAT" -Prompt "Enter your GitHub Personal Access Token (PAT):" -IsPassword $true
if (-not $GhPat) { Write-Log "User cancelled." "ERROR"; exit }

# Log collected information (without sensitive data)
Write-Log "Configuration Summary:" "INFO"
if ($migrateSingle) {
    Write-Log "Migration Type: SINGLE repository" "INFO"
    Write-Log "ADO Repo: $AdoRepo" "INFO"
    Write-Log "GitHub Repo: $GhRepo" "INFO"
} elseif ($migrateOneProject) {
    Write-Log "Migration Type: ALL repositories from ONE Team Project" "INFO"
} else {
    Write-Log "Migration Type: ALL repositories from ALL Team Projects" "INFO"
}
Write-Log "ADO Org: $AdoOrg" "INFO"
if ($AdoTeamProject) {
    Write-Log "ADO Team Project: $AdoTeamProject" "INFO"
}
Write-Log "GitHub Org: $GhOrg" "INFO"

# Check if gh CLI is installed
Write-Log "Checking for GitHub CLI (gh)..." "INFO"
try {
    $ghVersion = gh --version
    Write-Log "GitHub CLI is installed: $ghVersion" "INFO"
}
catch {
    Write-Log "GitHub CLI not found. Please install it first from https://cli.github.com/" "ERROR"
    Show-MessageBox -Title "Error" -Message "GitHub CLI (gh) is not installed.`n`nPlease install it from: https://cli.github.com/`n`nThen run this script again."
    exit
}

Write-Log "Authenticating with GitHub..." "INFO"

try {
    # Required for gh ado2gh
    $env:GITHUB_TOKEN = $GhPat

    # Optional: validate token works
    $null = gh api user 2>&1

    Write-Log "GitHub authentication successful" "INFO"
}
catch {
    Write-Log "GitHub authentication failed: $_" "ERROR"
    Show-MessageBox -Title "Error" -Message @"
GitHub authentication failed.

This tool requires a CLASSIC GitHub PAT with:
- repo
- admin:org
- workflow
"@
    exit
}

# Install gh-ado2gh extension
Write-Log "Installing gh-ado2gh extension..." "INFO"
try {
    gh extension install github/gh-ado2gh 2>&1 | Out-Null
    Write-Log "gh-ado2gh extension installed successfully" "INFO"
}
catch {
    Write-Log "Extension installation failed (may already be installed): $_" "WARN"
}

# Set environment variables
$env:ADO_PAT = $AdoPat


if ($migrateOneProject) {
    # Bulk Migration - Generate Script for All Repos in One Project
    Write-Log "Starting bulk migration process for all repositories in one project..." "INFO"
    Show-MessageBox -Title "Bulk Migration Starting" -Message "Generating migration script for ALL repositories in project: $AdoTeamProject`n`nThis may take a moment...`n`nPlease wait..."
    
    try {
        $scriptFile = "migration-script-$(Get-Date -Format 'yyyyMMdd-HHmmss').ps1"
        
        Write-Log "Generating migration script..." "INFO"
        $generateCommand = "gh ado2gh generate-script --ado-org ""$AdoOrg"" --ado-team-project ""$AdoTeamProject"" --github-org ""$GhOrg"" --output ""$scriptFile"""
        Write-Log "Command: $generateCommand" "INFO"
        
        Invoke-Expression $generateCommand
        
        if (Test-Path $scriptFile) {
            Write-Log "Migration script generated: $scriptFile" "INFO"
            
            $confirmRun = [System.Windows.Forms.MessageBox]::Show(
                "Migration script generated successfully!`n`nFile: $scriptFile`n`nDo you want to review the script before running it?`n`nClick YES to open in Notepad, NO to run immediately, CANCEL to exit.",
                "Script Generated",
                'YesNoCancel',
                'Question'
            )
            
            if ($confirmRun -eq 'Yes') {
                notepad $scriptFile
                $runScript = [System.Windows.Forms.MessageBox]::Show(
                    "Do you want to run the migration script now?",
                    "Run Migration",
                    'YesNo',
                    'Question'
                )
                
                if ($runScript -eq 'Yes') {
                    Write-Log "Executing migration script..." "INFO"
                    & ./$scriptFile
                    Write-Log "Bulk migration completed!" "INFO"
                    Show-MessageBox -Title "Success!" -Message "Bulk migration completed!`n`nCheck GitHub Organization: https://github.com/$GhOrg`n`nLog file: $LogFile`n`nCreated by: Swarup Puvvada"
                } else {
                    Write-Log "User chose not to run the script" "INFO"
                    Show-MessageBox -Title "Info" -Message "Migration script saved: $scriptFile`n`nYou can run it manually when ready."
                }
            } elseif ($confirmRun -eq 'No') {
                Write-Log "Executing migration script immediately..." "INFO"
                & ./$scriptFile
                Write-Log "Bulk migration completed!" "INFO"
                Show-MessageBox -Title "Success!" -Message "Bulk migration completed!`n`nCheck GitHub Organization: https://github.com/$GhOrg`n`nLog file: $LogFile`n`nCreated by: Swarup Puvvada"
            } else {
                Write-Log "User cancelled script execution" "INFO"
                Show-MessageBox -Title "Info" -Message "Migration script saved: $scriptFile`n`nYou can run it manually when ready."
            }
            
            # Open GitHub org in browser
            Start-Process "https://github.com/$GhOrg"
        } else {
            Write-Log "Failed to generate migration script" "ERROR"
            Show-MessageBox -Title "Error" -Message "Failed to generate migration script.`n`nCheck the log file for details: $LogFile"
        }
    }
    catch {
        Write-Log "Bulk migration failed: $_" "ERROR"
        Show-MessageBox -Title "Error" -Message "Bulk migration failed!`n`nError: $_`n`nCheck the log file for details: $LogFile"
        exit
    }
} elseif ($migrateAllProjects) {
    # Bulk Migration - Generate Script for All Repos in All Projects
    Write-Log "Starting bulk migration process for all repositories in all projects..." "INFO"
    Show-MessageBox -Title "Bulk Migration Starting" -Message "Generating migration script for ALL repositories in ALL Team Projects in organization: $AdoOrg`n`nThis may take a moment...`n`nPlease wait..."
    
    try {
        $scriptFile = "migration-script-$(Get-Date -Format 'yyyyMMdd-HHmmss').ps1"
        
        Write-Log "Generating migration script..." "INFO"
        $generateCommand = "gh ado2gh generate-script --ado-org ""$AdoOrg"" --github-org ""$GhOrg"" --output ""$scriptFile"""
        Write-Log "Command: $generateCommand" "INFO"
        
        Invoke-Expression $generateCommand
        
        if (Test-Path $scriptFile) {
            Write-Log "Migration script generated: $scriptFile" "INFO"
            
            $confirmRun = [System.Windows.Forms.MessageBox]::Show(
                "Migration script generated successfully!`n`nFile: $scriptFile`n`nDo you want to review the script before running it?`n`nClick YES to open in Notepad, NO to run immediately, CANCEL to exit.",
                "Script Generated",
                'YesNoCancel',
                'Question'
            )
            
            if ($confirmRun -eq 'Yes') {
                notepad $scriptFile
                $runScript = [System.Windows.Forms.MessageBox]::Show(
                    "Do you want to run the migration script now?",
                    "Run Migration",
                    'YesNo',
                    'Question'
                )
                
                if ($runScript -eq 'Yes') {
                    Write-Log "Executing migration script..." "INFO"
                    & ./$scriptFile
                    Write-Log "Bulk migration completed!" "INFO"
                    Show-MessageBox -Title "Success!" -Message "Bulk migration completed!`n`nCheck GitHub Organization: https://github.com/$GhOrg`n`nLog file: $LogFile`n`nCreated by: Swarup Puvvada"
                } else {
                    Write-Log "User chose not to run the script" "INFO"
                    Show-MessageBox -Title "Info" -Message "Migration script saved: $scriptFile`n`nYou can run it manually when ready."
                }
            } elseif ($confirmRun -eq 'No') {
                Write-Log "Executing migration script immediately..." "INFO"
                & ./$scriptFile
                Write-Log "Bulk migration completed!" "INFO"
                Show-MessageBox -Title "Success!" -Message "Bulk migration completed!`n`nCheck GitHub Organization: https://github.com/$GhOrg`n`nLog file: $LogFile`n`nCreated by: Swarup Puvvada"
            } else {
                Write-Log "User cancelled script execution" "INFO"
                Show-MessageBox -Title "Info" -Message "Migration script saved: $scriptFile`n`nYou can run it manually when ready."
            }
            
            # Open GitHub org in browser
            Start-Process "https://github.com/$GhOrg"
        } else {
            Write-Log "Failed to generate migration script" "ERROR"
            Show-MessageBox -Title "Error" -Message "Failed to generate migration script.`n`nCheck the log file for details: $LogFile"
        }
    }
    catch {
        Write-Log "Bulk migration failed: $_" "ERROR"
        Show-MessageBox -Title "Error" -Message "Bulk migration failed!`n`nError: $_`n`nCheck the log file for details: $LogFile"
        exit
    }
} else {
    # Single Repository Migration
    Write-Log "Starting single repository migration process..." "INFO"
    Show-MessageBox -Title "Migration Starting" -Message "The migration process is about to start.`n`nRepository: $AdoRepo -> $GhRepo`n`nThis may take several minutes depending on repository size.`n`nPlease wait..."
    
    try {
        $migrationCommand = "gh ado2gh migrate-repo --ado-org ""$AdoOrg"" --ado-team-project ""$AdoTeamProject"" --ado-repo ""$AdoRepo"" --github-org ""$GhOrg"" --github-repo ""$GhRepo"""
        
        Write-Log "Executing migration command..." "INFO"
        Write-Log "Command: gh ado2gh migrate-repo --ado-org $AdoOrg --ado-team-project $AdoTeamProject --ado-repo $AdoRepo --github-org $GhOrg --github-repo $GhRepo" "INFO"
        
        Invoke-Expression $migrationCommand
        
        Write-Log "Migration completed successfully!" "INFO"
        Show-MessageBox -Title "Success!" -Message "Migration completed successfully!`n`nRepository: https://github.com/$GhOrg/$GhRepo`n`nCheck the log file for details: $LogFile`n`nCreated by: Swarup Puvvada"
        
        # Open the migrated repository in browser
        Start-Process "https://github.com/$GhOrg/$GhRepo"
    }
    catch {
        Write-Log "Migration failed: $_" "ERROR"
        Show-MessageBox -Title "Error" -Message "Migration failed!`n`nError: $_`n`nCheck the log file for details: $LogFile"
        exit
    }
}

Write-Log "========================================" "INFO"
Write-Log "Script execution completed" "INFO"
Write-Log "========================================" "INFO"

# Cleanup sensitive environment variables
Remove-Item Env:\ADO_PAT -ErrorAction SilentlyContinue
Remove-Item Env:\GH_TOKEN -ErrorAction SilentlyContinue

Write-Host "`nScript completed. Log file: $LogFile" -ForegroundColor Green
Read-Host "`nPress Enter to exit"