<#
    MidgardPlus installer  -  Odin the Red
    https://midgardplus.vardynbot.com

    Installs BepInEx (Valheim pack), Jotunn and MidgardPlus into your Valheim folder.

    Run:
        irm https://midgardplus.vardynbot.com/install.ps1 | iex

    Nothing here runs as admin, nothing touches the registry, and nothing is uninstalled.
    Every file it writes lives inside your Valheim folder. To undo it, delete BepInEx,
    winhttp.dll, doorstop_config.ini and doorstop_libs from that folder.
#>

$ErrorActionPreference = 'Stop'
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12

$BepInEx  = 'https://thunderstore.io/package/download/denikson/BepInExPack_Valheim/5.4.2350/'
$Jotunn   = 'https://thunderstore.io/package/download/ValheimModding/Jotunn/2.30.0/'
$Midgard  = 'https://midgardplus.vardynbot.com/MidgardPlus-1.1.0.zip'

function Say($msg, $colour = 'Gray') { Write-Host $msg -ForegroundColor $colour }

Say ''
Say '  MidgardPlus installer' Yellow
Say '  by Odin the Red' DarkYellow
Say ''

# ---------------------------------------------------------------- find Valheim
function Find-Valheim {
    # The usual place first.
    $guess = Join-Path ${env:ProgramFiles(x86)} 'Steam\steamapps\common\Valheim'
    if (Test-Path (Join-Path $guess 'valheim.exe')) { return $guess }

    # Otherwise ask Steam where its libraries are.
    $steam = $null
    foreach ($key in @('HKCU:\Software\Valve\Steam', 'HKLM:\SOFTWARE\WOW6432Node\Valve\Steam')) {
        try {
            $p = (Get-ItemProperty -Path $key -ErrorAction Stop).SteamPath
            if ($p) { $steam = $p.Replace('/', '\'); break }
        } catch { }
    }
    if (-not $steam) { return $null }

    $candidates = @(Join-Path $steam 'steamapps\common\Valheim')

    $vdf = Join-Path $steam 'steamapps\libraryfolders.vdf'
    if (Test-Path $vdf) {
        foreach ($line in Get-Content $vdf) {
            if ($line -match '"path"\s+"(.+?)"') {
                $lib = $matches[1].Replace('\\', '\')
                $candidates += (Join-Path $lib 'steamapps\common\Valheim')
            }
        }
    }

    foreach ($c in $candidates) {
        if (Test-Path (Join-Path $c 'valheim.exe')) { return $c }
    }
    return $null
}

$game = Find-Valheim

if (-not $game) {
    Say '  Could not find Valheim automatically.' Red
    Say ''
    $game = Read-Host '  Paste the folder containing valheim.exe'
    $game = $game.Trim('"').Trim()
    if (-not (Test-Path (Join-Path $game 'valheim.exe'))) {
        Say '  No valheim.exe in that folder. Nothing was changed.' Red
        return
    }
}

Say "  Valheim: $game" Green
Say ''

# ---------------------------------------------------------------- download
$work = Join-Path $env:TEMP ("midgardplus-" + [Guid]::NewGuid().ToString('N').Substring(0, 8))
New-Item -ItemType Directory -Path $work -Force | Out-Null

function Fetch($url, $name) {
    $out = Join-Path $work $name
    Say "  Downloading $name ..."
    Invoke-WebRequest -Uri $url -OutFile $out -UseBasicParsing
    return $out
}

function Unpack($zip, $name) {
    $dir = Join-Path $work ($name + '-x')
    Expand-Archive -Path $zip -DestinationPath $dir -Force
    return $dir
}

try {
    $bepZip = Fetch $BepInEx 'BepInExPack_Valheim.zip'
    $jotZip = Fetch $Jotunn  'Jotunn.zip'
    $midZip = Fetch $Midgard 'MidgardPlus.zip'

    Say ''
    Say '  Installing ...'

    # --- BepInEx: the pack nests everything under BepInExPack_Valheim\
    $bepDir = Unpack $bepZip 'bep'
    $inner  = Join-Path $bepDir 'BepInExPack_Valheim'
    $src    = if (Test-Path $inner) { $inner } else { $bepDir }
    Copy-Item -Path (Join-Path $src '*') -Destination $game -Recurse -Force
    Say '    BepInEx' DarkGray

    $plugins = Join-Path $game 'BepInEx\plugins'
    New-Item -ItemType Directory -Path $plugins -Force | Out-Null

    # --- Jotunn: plugins\Jotunn.dll
    $jotDir = Unpack $jotZip 'jot'
    $jotDll = Get-ChildItem -Path $jotDir -Filter 'Jotunn.dll' -Recurse | Select-Object -First 1
    if (-not $jotDll) { throw 'Jotunn.dll was not in the download.' }
    Copy-Item $jotDll.FullName -Destination $plugins -Force
    Say '    Jotunn' DarkGray

    # --- MidgardPlus: its own folder, so uninstalling is one delete
    $midDir = Unpack $midZip 'mid'
    $midDll = Get-ChildItem -Path $midDir -Filter 'MidgardPlus.dll' -Recurse | Select-Object -First 1
    if (-not $midDll) { throw 'MidgardPlus.dll was not in the download.' }
    $target = Join-Path $plugins 'MidgardPlus'
    New-Item -ItemType Directory -Path $target -Force | Out-Null
    Copy-Item $midDll.FullName -Destination $target -Force
    Say '    MidgardPlus' DarkGray

    Say ''
    Say '  Done.' Green
    Say ''
    Say '  Start Valheim once, then edit your settings here:' Gray
    Say "    $game\BepInEx\config\midgardplus.cfg" Yellow
    Say ''
    Say '  Everything starts at vanilla, so nothing changes until you turn it on.' DarkGray
    Say ''
}
catch {
    Say ''
    Say "  Install failed: $($_.Exception.Message)" Red
    Say '  Nothing was left half-written outside your Valheim folder.' DarkGray
    Say '  Manual download: https://midgardplus.vardynbot.com' Gray
    Say ''
}
finally {
    Remove-Item $work -Recurse -Force -ErrorAction SilentlyContinue
}