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+# WelsonJS One-Click Installer (install.ps1) 
+# Copyright 2019-2025, Namhyeon Go <gnh1201@catswords.re.kr> and the WelsonJS contributors.
+# SPDX-License-Identifier: GPL-3.0-or-later
+# https://github.com/gnh1201/welsonjs
+# 
+# Usage:
+#   irm https://welson.js.org/install.ps1 | iex
+#   irm https://welson.js.org/install.ps1 | iex -dev main
+#   irm https://welson.js.org/install.ps1 | iex -dev dev
+# 
+# Central default branch configuration for this install script.
+# Update this value if the repository's default branch changes.
+$DefaultBranch = "master"
+
+param(
+    # Branch to install from; defaults to the repository's configured primary branch.
+    [string]$dev = $DefaultBranch
+)
+
+$ErrorActionPreference = "Stop"
+
+function Write-Step($msg) {
+    Write-Host "[*] $msg" -ForegroundColor Cyan
+}
+
+function Write-Ok($msg) {
+    Write-Host "[+] $msg" -ForegroundColor Green
+}
+
+function Write-Err($msg) {
+    Write-Host "[!] $msg" -ForegroundColor Red
+}
+
+try {
+    # Step 1: Create a temporary working directory using a UUID
+    Write-Step "Creating temporary workspace..."
+
+    $uuid = [guid]::NewGuid().ToString()
+    $tempDir = Join-Path $env:TEMP $uuid
+
+    New-Item -ItemType Directory -Path $tempDir | Out-Null
+
+    Write-Ok "Temp directory: $tempDir"
+
+    $repo = "gnh1201/welsonjs"
+    $zipPath = Join-Path $tempDir "package.zip"
+
+    # Step 2: Determine branch (default: master)
+    $branch = $dev
+
+    Write-Step "Using branch: $branch"
+
+    # GitHub branch ZIP URL
+    $downloadUrl = "https://github.com/$repo/archive/refs/heads/$branch.zip"
+
+    Write-Ok "Download URL: $downloadUrl"
+
+    # Step 3: Download the ZIP package
+    Write-Step "Downloading package..."
+
+    irm $downloadUrl -OutFile $zipPath
+
+    Write-Ok "Downloaded: $zipPath"
+
+    # Step 4: Extract the ZIP archive
+    Write-Step "Extracting package..."
+
+    Expand-Archive -Path $zipPath -DestinationPath $tempDir
+
+    Write-Ok "Extraction completed"
+
+    # Step 5: Locate bootstrap.bat within extracted files
+    Write-Step "Locating bootstrap.bat..."
+
+    $bootstrap = Get-ChildItem -Path $tempDir -Recurse -Filter "bootstrap.bat" | Select-Object -First 1
+
+    if (-not $bootstrap) {
+        throw "bootstrap.bat not found"
+    }
+
+    Write-Ok "Found: $($bootstrap.FullName)"
+
+    # Step 6: Execute bootstrap.bat via cmd.exe for compatibility
+    Write-Step "Executing bootstrap..."
+
+    $proc = Start-Process -FilePath "cmd.exe" `
+        -ArgumentList "/c `"$($bootstrap.FullName)`"" `
+        -Wait -PassThru
+
+    if ($proc.ExitCode -ne 0) {
+        throw "bootstrap failed with exit code $($proc.ExitCode)"
+    }
+
+    Write-Ok "Bootstrap executed successfully"
+
+    # Step 7: Final message
+    Write-Host ""
+    Write-Host "WelsonJS installation completed!" -ForegroundColor Green
+    Write-Host ""
+
+}
+catch {
+    Write-Err $_
+    exit 1
+}