#Requires -Version 5.1
# Public release repository: https://eightarms.net/fourbroad/octopus-release
<#
.SYNOPSIS
    Octopus installer for Windows.

.DESCRIPTION
    Downloads and installs the Octopus CLI from Gitea Releases.

.PARAMETER Version
    Install a specific version (e.g. 1.0.180). Defaults to latest.

.PARAMETER NoModifyPath
    Do not add the install directory to the user PATH.

.EXAMPLE
    [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
    irm https://eightarms.net/fourbroad/octopus-release/raw/branch/main/install.ps1 | iex

.EXAMPLE
    [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
    irm https://eightarms.net/fourbroad/octopus-release/raw/branch/main/install.ps1 | iex; Install-Octopus -Version 0.1.3
#>
[CmdletBinding()]
param(
    [string]$Version = "",
    [switch]$NoModifyPath
)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12

$APP       = "octopus"
$REPO      = "fourbroad/octopus-release"
$baseUrl   = if ($env:OCTOPUS_DOWNLOAD_BASE) { $env:OCTOPUS_DOWNLOAD_BASE } else { "https://eightarms.net" }
$INSTALL_DIR = Join-Path $env:USERPROFILE ".octopus\bin"

function Write-Color([string]$Text, [string]$Color = "White") {
    Write-Host $Text -ForegroundColor $Color
}

function Get-Arch {
    $arch = $env:PROCESSOR_ARCHITECTURE
    if ($arch -eq "AMD64") { return "x64" }
    if ($arch -eq "ARM64") { return "arm64" }
    throw "Unsupported architecture: $arch"
}

function Test-Avx2Support {
    try {
        Add-Type -MemberDefinition @"
            [System.Runtime.InteropServices.DllImport("kernel32.dll")]
            public static extern bool IsProcessorFeaturePresent(int ProcessorFeature);
"@ -Name "Kernel32" -Namespace "Win32" -ErrorAction SilentlyContinue | Out-Null
        # PF_AVX2_INSTRUCTIONS_AVAILABLE = 40
        return [Win32.Kernel32]::IsProcessorFeaturePresent(40)
    } catch {
        return $false
    }
}

function Get-LatestVersion {
    # Resolve the latest version by following the /releases/latest redirect to
    # /releases/tag/vX.Y.Z. This avoids the API, which is
    # rate-limited to 60 requests/hour per IP.
    $latestUrl = "$baseUrl/$REPO/releases/latest"
    $location = $null
    $request = [System.Net.HttpWebRequest]::Create($latestUrl)
    $request.Method = "HEAD"
    $request.AllowAutoRedirect = $false
    $request.UserAgent = "octopus-installer"
    try {
        $response = $request.GetResponse()
        $location = $response.Headers["Location"]
        $response.Close()
    } catch [System.Net.WebException] {
        $resp = $_.Exception.Response
        if ($null -ne $resp) {
            $location = $resp.Headers["Location"]
            $resp.Close()
        }
    }
    if (-not $location) { return "" }
    if ($location -match '/tag/v?([^/]+)/?$') {
        return $Matches[1] -replace '^v', ''
    }
    return ""
}

function Install-Octopus {
    $arch = Get-Arch

    # Resolve version
    if ($Version -ne "") {
        $specificVersion = $Version -replace '^v', ''
        # Verify release exists
        $releaseUrl = "$baseUrl/$REPO/releases/tag/v$specificVersion"
        try {
            $null = Invoke-WebRequest -Uri $releaseUrl -Method Head -UseBasicParsing -ErrorAction Stop
        } catch {
            Write-Color "Error: Release v$specificVersion not found." "Red"
            Write-Color "Available releases: $baseUrl/$REPO/releases" "DarkGray"
            exit 1
        }
    } else {
        Write-Color "Fetching latest version..." "DarkGray"
        $specificVersion = Get-LatestVersion
        if (-not $specificVersion) {
            Write-Color "Error: Failed to fetch latest version." "Red"
            exit 1
        }
    }

    # Check if already installed at this version
    $existing = Join-Path $INSTALL_DIR "$APP.exe"
    if (Test-Path $existing) {
        try {
            $installedVersion = & $existing --version 2>$null
            if ($installedVersion -eq $specificVersion) {
                Write-Color "Version $specificVersion already installed." "DarkGray"
                exit 0
            } else {
                Write-Color "Installed version: $installedVersion" "DarkGray"
            }
        } catch { }
    }

    # Build filename
    $target = "$APP-windows-$arch"
    if ($arch -eq "x64" -and -not (Test-Avx2Support)) {
        $target = "$APP-windows-$arch-baseline"
    }
    $filename  = "$target.zip"
    $downloadUrl = "$baseUrl/$REPO/releases/download/v$specificVersion/$filename"

    Write-Color ""
    Write-Color "Installing octopus version: $specificVersion" "DarkGray"
    Write-Color "Downloading $filename ..." "DarkGray"

    # Download
    $tmpDir = Join-Path $env:TEMP "octopus_install_$PID"
    New-Item -ItemType Directory -Path $tmpDir -Force | Out-Null
    $zipPath = Join-Path $tmpDir $filename

    try {
        $ProgressPreference = "SilentlyContinue"
        Invoke-WebRequest -Uri $downloadUrl -OutFile $zipPath -UseBasicParsing
    } catch {
        Write-Color "Error: Failed to download $downloadUrl" "Red"
        Write-Color $_.Exception.Message "Red"
        Remove-Item -Recurse -Force $tmpDir -ErrorAction SilentlyContinue
        exit 1
    }

    # Extract
    Expand-Archive -Path $zipPath -DestinationPath $tmpDir -Force

    # Install
    New-Item -ItemType Directory -Path $INSTALL_DIR -Force | Out-Null
    $exeSrc = Join-Path $tmpDir "$APP.exe"
    if (-not (Test-Path $exeSrc)) {
        Write-Color "Error: $APP.exe not found in archive." "Red"
        Remove-Item -Recurse -Force $tmpDir -ErrorAction SilentlyContinue
        exit 1
    }
    Copy-Item -Path $exeSrc -Destination (Join-Path $INSTALL_DIR "$APP.exe") -Force
    Remove-Item -Recurse -Force $tmpDir -ErrorAction SilentlyContinue

    # Add to PATH
    if (-not $NoModifyPath) {
        $userPath = [Environment]::GetEnvironmentVariable("PATH", "User")
        if ($userPath -notlike "*$INSTALL_DIR*") {
            [Environment]::SetEnvironmentVariable("PATH", "$INSTALL_DIR;$userPath", "User")
            Write-Color "Added $INSTALL_DIR to user PATH." "DarkGray"
            Write-Color "Restart your terminal for PATH changes to take effect." "Yellow"
        }
    }

    # CI Actions support (GitHub/Gitea)
    if ($env:GITHUB_ACTIONS -eq "true" -and $env:GITHUB_PATH) {
        Add-Content -Path $env:GITHUB_PATH -Value $INSTALL_DIR
        Write-Color "Added $INSTALL_DIR to GITHUB_PATH." "DarkGray"
    }

    Write-Host ""
    Write-Host "  ___       _"                                    -ForegroundColor DarkYellow
    Write-Host " / _ \  ___| |_ ___  _ __  _   _ ___"            -ForegroundColor DarkYellow
    Write-Host "| | | |/ __| __/ _ \| '_ \| | | / __|"           -ForegroundColor Yellow
    Write-Host "| |_| | (__| || (_) | |_) | |_| \__ \"           -ForegroundColor Yellow
    Write-Host " \___/ \___|\__\___/| .__/ \__,_|___/"            -ForegroundColor White
    Write-Host "                    |_|"                           -ForegroundColor White
    Write-Host ""
    Write-Host "Octopus includes free models, to start:" -ForegroundColor DarkGray
    Write-Host ""
    Write-Host "  cd <project>   " -NoNewline; Write-Host "# Open directory" -ForegroundColor DarkGray
    Write-Host "  octopus        " -NoNewline; Write-Host "# Run command"    -ForegroundColor DarkGray
    Write-Host ""
    Write-Host "For more information visit " -NoNewline -ForegroundColor DarkGray
    Write-Host "https://eightarms.net/fourbroad/octopus-release"
    Write-Host ""
}

Install-Octopus