#Requires -Version 5.1
<#
.SYNOPSIS
    Installs ctop (container terminal UI) from GitHub releases.

.DESCRIPTION
    Auto-detects the latest release from
    https://github.com/bcicen/ctop/releases, downloads the binary
    matching your Windows architecture, and installs it.

    Supported architectures:
      - x64  (AMD64 / Intel 64bit)

    NOTE: ctop only provides a windows-amd64 binary. ARM64 is not supported.

.PARAMETER InstallDir
    Directory to install ctop.exe. Default: $env:USERPROFILE\.local\bin

.PARAMETER AddToPath
    Whether to permanently add InstallDir to user PATH. Default: $true

.EXAMPLE
    .\install-ctop.ps1
    .\install-ctop.ps1 -InstallDir "C:\tools\bin"
    .\install-ctop.ps1 -AddToPath $false

    # One-liner install from remote (download then run; -ExecutionPolicy Bypass for current process only):
    powershell -ExecutionPolicy Bypass -c "$t=\"$env:TEMP\install-ctop.ps1\"; iwr -useb 'https://gl.isitsoft.kr/publicproj/install-sh/-/raw/main/install-ctop.ps1' -OutFile $t; & $t"

    # With parameters:
    powershell -ExecutionPolicy Bypass -c "$t=\"$env:TEMP\install-ctop.ps1\"; iwr -useb 'https://gl.isitsoft.kr/publicproj/install-sh/-/raw/main/install-ctop.ps1' -OutFile $t; & $t -InstallDir 'C:\tools\bin'"

.NOTES
    If execution policy error occurs:
      Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser
#>

[CmdletBinding()]
param(
    [string] $InstallDir = "$env:USERPROFILE\.local\bin",
    [bool]   $AddToPath = $true
)

Set-StrictMode -Version Latest
$ErrorActionPreference = 'Stop'

# ────────────────────────────────────────────
# Constants
# ────────────────────────────────────────────
$REPO    = "bcicen/ctop"
$API_URL = "https://api.github.com/repos/$REPO/releases"

# ────────────────────────────────────────────
# Utility functions
# ────────────────────────────────────────────
function Write-Info    { param([string]$msg) Write-Host "[INFO]  $msg" -ForegroundColor Cyan }
function Write-Warn    { param([string]$msg) Write-Host "[WARN]  $msg" -ForegroundColor Yellow }
function Write-Success { param([string]$msg) Write-Host "[OK]    $msg" -ForegroundColor Green }
function Write-Err     { param([string]$msg) Write-Host "[ERROR] $msg" -ForegroundColor Red; exit 1 }

# ────────────────────────────────────────────
# Enforce TLS 1.2 (for Windows 7/8.1 compatibility)
# ────────────────────────────────────────────
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12

# ────────────────────────────────────────────
# Architecture detection
# ────────────────────────────────────────────
function Get-Platform {
    # ctop only provides windows-amd64 binary
    $envArch = $env:PROCESSOR_ARCHITEW6432
    if (-not $envArch) { $envArch = $env:PROCESSOR_ARCHITECTURE }

    switch -Regex ($envArch) {
        '^AMD64$' { return "windows-amd64" }
        '^ARM64$' {
            Write-Warn "ctop does not provide a native ARM64 Windows build."
            Write-Warn "Falling back to amd64 binary (may run via emulation)."
            return "windows-amd64"
        }
        '^x86$'   { Write-Err "ctop does not provide a 32-bit Windows build." }
    }

    try {
        $arch = [System.Runtime.InteropServices.RuntimeInformation]::OSArchitecture
        switch ($arch) {
            'X64'   { return "windows-amd64" }
            'Arm64' {
                Write-Warn "ctop does not provide a native ARM64 Windows build."
                Write-Warn "Falling back to amd64 binary (may run via emulation)."
                return "windows-amd64"
            }
            'X86'   { Write-Err "ctop does not provide a 32-bit Windows build." }
            default { Write-Err "Unsupported architecture: $arch" }
        }
    } catch {
        Write-Err "Failed to detect architecture: $_"
    }
}

# ────────────────────────────────────────────
# Get latest stable release tag
# ────────────────────────────────────────────
function Get-LatestTag {
    Write-Info "Fetching latest release from GitHub API..."

    try {
        $releases = Invoke-RestMethod -Uri $API_URL -UseBasicParsing `
            -Headers @{ 'User-Agent' = 'install-ctop-ps1' }
    } catch {
        Write-Err "Failed to call GitHub API: $_"
    }

    $latest = $releases | Where-Object { $_.prerelease -eq $false } | Select-Object -First 1

    if (-not $latest) {
        Write-Err "Could not find latest release."
    }

    return $latest.tag_name
}

# ────────────────────────────────────────────
# Build download URL
# ────────────────────────────────────────────
# ctop release assets: ctop-{version}-{os}-{arch} (raw binary, no .exe extension)
function Get-DownloadUrl {
    param([string]$Tag, [string]$Platform)
    $version = $Tag -replace '^v', ''
    $filename = "ctop-${version}-${Platform}"
    return "https://github.com/$REPO/releases/download/$Tag/$filename"
}

# ────────────────────────────────────────────
# Download & install (raw binary — no archive extraction needed)
# ────────────────────────────────────────────
function Install-Ctop {
    param([string]$Url)

    $tmpDir = Join-Path $env:TEMP "ctop_install_$(Get-Random)"
    New-Item -ItemType Directory -Path $tmpDir | Out-Null

    try {
        $binPath = Join-Path $tmpDir "ctop"

        Write-Info "Downloading: $Url"
        try {
            $ProgressPreference = 'SilentlyContinue'
            Invoke-WebRequest -Uri $Url -OutFile $binPath -UseBasicParsing
            $ProgressPreference = 'Continue'
        } catch {
            Write-Err "Download failed: $_"
        }

        # Create install directory
        if (-not (Test-Path $InstallDir)) {
            New-Item -ItemType Directory -Path $InstallDir -Force | Out-Null
        }

        $destPath = Join-Path $InstallDir "ctop.exe"
        Write-Info "Installing: $destPath"
        Copy-Item -Path $binPath -Destination $destPath -Force

        Write-Success "Installation complete!"

        Write-Info "Version check:"
        & $destPath -v

    } finally {
        if (Test-Path $tmpDir) {
            Remove-Item -Path $tmpDir -Recurse -Force -ErrorAction SilentlyContinue
        }
    }
}

# ────────────────────────────────────────────
# Add to PATH (user environment variable)
# ────────────────────────────────────────────
function Add-ToUserPath {
    param([string]$Dir)

    $currentPath = [Environment]::GetEnvironmentVariable('PATH', 'User')
    if (-not $currentPath) { $currentPath = '' }
    $dirs = @($currentPath -split ';' | Where-Object { $_ -ne '' })

    if ($dirs -contains $Dir) {
        Write-Info "'$Dir' is already in your PATH."
        return
    }

    $newPath = ($dirs + $Dir) -join ';'
    [Environment]::SetEnvironmentVariable('PATH', $newPath, 'User')

    $env:PATH = "$env:PATH;$Dir"

    Write-Success "'$Dir' has been permanently added to user PATH."
    Write-Warn "Open a new terminal for PATH changes to take effect."
}

# ────────────────────────────────────────────
# Main
# ────────────────────────────────────────────
function Main {
    Write-Info "===== ctop install script (Windows PowerShell) ====="

    $platform = Get-Platform
    Write-Info "Detected platform: $platform"

    $tag = Get-LatestTag
    Write-Info "Latest release: $tag"

    $url = Get-DownloadUrl -Tag $tag -Platform $platform
    Install-Ctop -Url $url

    if ($AddToPath) {
        Add-ToUserPath -Dir $InstallDir
    } else {
        Write-Warn "Skipping automatic PATH registration."
        Write-Warn "Add to PATH manually: $InstallDir"
    }

    Write-Success "All tasks completed."
    Write-Info  "Usage: ctop"
}

Main