# Unitx SkyMP installer — instala el cliente SkyMP en una carpeta de Skyrim SE
# y lo apunta al server unitx (195.26.241.62:7777).
#
# Requisitos:
#  - Skyrim Special Edition instalado vía Steam
#  - SKSE64 instalado en la carpeta de Skyrim
#  - El zip 'dist' del CI de skymp ya descargado en disco
#
# Uso:
#   .\Install-UnitxSkyMP.ps1
#
# Para sobreescribir parámetros del server:
#   .\Install-UnitxSkyMP.ps1 -ServerIp 'otra-ip' -ServerPort 7778

[CmdletBinding()]
param(
    [string] $DistZipPath,
    [string] $SkyrimPath,
    [string] $ServerIp = '195.26.241.62',
    # 25565 (puerto Minecraft) en lugar del default skymp 7777 — ISPs LATAM
    # frecuentemente filtran UDP 7777. Comprobado: UDP 7777 daba 80% loss, 25565 0%.
    [int]    $ServerPort = 25565,
    # Master server propio (Fase 3): el panel skymp-admin implementa los endpoints
    # de auth/sessions; el cliente abre Discord OAuth in-game, valida guild y nos
    # devuelve session → server consume session.
    [string] $ServerMasterKey = 'unitx-skymp',
    [string] $MasterUrl       = 'https://skymp.unitx-wow.com.mx',
    [switch] $LaunchAfterInstall
)

$ErrorActionPreference = 'Stop'

# Log permanente para diagnóstico — siempre se escribe, ganas o pierdas.
$logDir = Join-Path $env:LOCALAPPDATA 'UnitxSkyMP\logs'
if (-not (Test-Path $logDir)) { New-Item -ItemType Directory -Path $logDir -Force | Out-Null }
$script:LogPath = Join-Path $logDir ("install-{0}.log" -f (Get-Date -Format 'yyyyMMdd-HHmmss'))
Start-Transcript -Path $script:LogPath -Append | Out-Null

function Write-Section($text) {
    Write-Host ''
    Write-Host ('━' * 60) -ForegroundColor DarkGray
    Write-Host $text -ForegroundColor Cyan
    Write-Host ('━' * 60) -ForegroundColor DarkGray
}

function Resolve-SkyrimSEPath {
    if ($SkyrimPath -and (Test-Path $SkyrimPath)) { return (Resolve-Path $SkyrimPath).Path }

    # Steam install path detection
    $steamRoot = $null
    foreach ($key in @(
        'HKLM:\SOFTWARE\WOW6432Node\Valve\Steam',
        'HKLM:\SOFTWARE\Valve\Steam',
        'HKCU:\SOFTWARE\Valve\Steam'
    )) {
        try {
            $val = (Get-ItemProperty -Path $key -ErrorAction Stop).InstallPath
            if ($val) { $steamRoot = $val; break }
        } catch { }
    }

    if (-not $steamRoot) {
        Write-Warning 'No se detectó Steam en el registro.'
        return Read-Host 'Pega la ruta completa a tu carpeta "Skyrim Special Edition"'
    }

    # Read libraryfolders.vdf to find all Steam libraries
    $libraries = @($steamRoot)
    $libVdf = Join-Path $steamRoot 'steamapps\libraryfolders.vdf'
    if (Test-Path $libVdf) {
        $content = Get-Content $libVdf -Raw
        foreach ($m in [regex]::Matches($content, '"path"\s+"([^"]+)"')) {
            $libraries += $m.Groups[1].Value -replace '\\\\', '\'
        }
    }

    foreach ($lib in $libraries | Select-Object -Unique) {
        $candidate = Join-Path $lib 'steamapps\common\Skyrim Special Edition'
        if (Test-Path $candidate) { return (Resolve-Path $candidate).Path }
    }

    Write-Warning 'No se encontró Skyrim SE en ninguna biblioteca de Steam.'
    return Read-Host 'Pega la ruta completa a tu carpeta "Skyrim Special Edition"'
}

function Test-SKSE($skyrimDir) {
    $loader = Join-Path $skyrimDir 'skse64_loader.exe'
    if (Test-Path $loader) { return $true }
    Write-Warning "skse64_loader.exe NO se encontró en $skyrimDir"
    Write-Host '  Descarga SKSE Special Edition desde: https://skse.silverlock.org/' -ForegroundColor Yellow
    Write-Host '  Copia los archivos del zip dentro de tu carpeta "Skyrim Special Edition" y vuelve a correr este script.' -ForegroundColor Yellow
    return $false
}

function Resolve-DistZip {
    if ($DistZipPath -and (Test-Path $DistZipPath)) { return (Resolve-Path $DistZipPath).Path }

    Write-Host ''
    Write-Host 'Necesito el zip "dist" que bajaste de GitHub Actions.' -ForegroundColor Yellow
    Write-Host '  Si no lo tienes: ve a un run reciente de "PR Windows Flatrim (AE/SE)" en' -ForegroundColor Gray
    Write-Host '  https://github.com/skyrim-multiplayer/skymp/actions/workflows/pr-windows-flatrim.yml' -ForegroundColor Gray
    Write-Host '  y descarga el artifact "dist" (~186 MB).' -ForegroundColor Gray
    Write-Host ''
    $p = Read-Host 'Pega la ruta completa al dist.zip'
    if (-not (Test-Path $p)) { throw "No existe: $p" }
    return (Resolve-Path $p).Path
}

function Expand-DistInto($zipPath, $skyrimDir) {
    $temp = Join-Path $env:TEMP "unitx-skymp-$([guid]::NewGuid())"
    New-Item -ItemType Directory -Path $temp | Out-Null
    try {
        Write-Host "  Extrayendo a $temp ..." -ForegroundColor DarkGray
        Expand-Archive -Path $zipPath -DestinationPath $temp -Force

        # The CI 'dist' artifact may use either layout:
        #   <root>/Data/...           (already merge-ready)
        #   <root>/client/Data/...    (older layout)
        # Detect and pick the right base.
        $dataRoot = $null
        if (Test-Path (Join-Path $temp 'Data')) {
            $dataRoot = $temp
        } elseif (Test-Path (Join-Path $temp 'client\Data')) {
            $dataRoot = Join-Path $temp 'client'
        } else {
            $found = Get-ChildItem -Path $temp -Recurse -Directory -Filter 'Data' -ErrorAction SilentlyContinue |
                Where-Object { Test-Path (Join-Path $_.FullName 'Platform') } |
                Select-Object -First 1
            if ($found) { $dataRoot = Split-Path -Parent $found.FullName }
        }

        if (-not $dataRoot) {
            throw "No encontré 'Data/Platform' dentro del zip. ¿Es realmente el artifact 'dist'?"
        }

        Write-Host "  Copiando archivos del cliente a $skyrimDir ..." -ForegroundColor DarkGray
        Copy-Item -Path (Join-Path $dataRoot '*') -Destination $skyrimDir -Recurse -Force
    } finally {
        Remove-Item -Path $temp -Recurse -Force -ErrorAction SilentlyContinue
    }
}

function Write-ClientSettings($skyrimDir) {
    $settingsPath = Join-Path $skyrimDir 'Data\Platform\Plugins\skymp5-client-settings.txt'
    $dir = Split-Path -Parent $settingsPath
    if (-not (Test-Path $dir)) {
        throw "Directorio de plugins no existe: $dir. ¿Se extrajo correctamente el dist?"
    }

    # Public key Ed25519 del server. El engine firma cada JS de gamemode con
    # `// skymp:sig:y:CPPunitx:<sig>` (ver server-settings.json:serverKey). El
    # cliente requiere `server-public-keys` (o un fetch exitoso de serverinfo)
    # para poder verificar; si el map de public keys queda vacío, el cliente
    # rechaza TODO el JS pusheado por el server y no aparece chat ni nada.
    $serverPublicKeyPem = "-----BEGIN PUBLIC KEY-----`nMCowBQYDK2VwAyEAyhU5i/hjbUJPOF+HVaGx8/OI8w8XWJzNz2xUPWilDe8=`n-----END PUBLIC KEY-----`n"

    $settings = [ordered]@{
        'server-ip'                = $ServerIp
        'server-port'              = $ServerPort
        # Master server propio (no gateway.skymp.net). El cliente fetcha
        # serverinfo (publicKeys) y dispara el flujo Discord OAuth contra acá.
        'server-master-key'        = $ServerMasterKey
        'master'                   = $MasterUrl
        # server-info-ignore=false → cliente fetcha /api/servers/<key>/serverinfo
        # del master para obtener publicKeys. Lo dejamos resilente con keys
        # también en server-public-keys por si el master está caído.
        'server-info-ignore'       = $false
        'server-public-keys'       = @{ 'CPPunitx' = $serverPublicKeyPem }
        # AE 1.6.x trae muchos CC content + ResourcePack que el server vanilla no
        # incluye. Sin esto, el cliente cae a single-player con LOAD ORDER ERROR.
        'ignoreLoadOrderMismatch'  = $true
    }
    $json = $settings | ConvertTo-Json -Depth 4
    # WriteAllText with UTF8Encoding(false) -> NO BOM. Set-Content -Encoding UTF8 in
    # PS 5.x writes BOM, which breaks the skymp client's JSON.parse on this file.
    [System.IO.File]::WriteAllText($settingsPath, $json, [System.Text.UTF8Encoding]::new($false))
    Write-Host "  Config escrita en: $settingsPath (UTF-8 sin BOM)" -ForegroundColor DarkGray

    # Verificacion explicita - si esto falla algo se rompio en serio
    $verify = Get-Content $settingsPath -Raw | ConvertFrom-Json
    $ok = $true
    if ($verify.'server-port' -ne $ServerPort) {
        Write-Host "  *** ERROR: server-port no escrito correctamente ***" -ForegroundColor Red
        $ok = $false
    }
    if (-not $verify.master) {
        Write-Host "  *** ERROR: master URL vacio (auth Discord no funciona) ***" -ForegroundColor Red
        $ok = $false
    }
    if (-not $verify.'server-public-keys'.CPPunitx) {
        Write-Host "  *** ERROR: server-public-keys.CPPunitx falta ***" -ForegroundColor Red
        $ok = $false
    }
    if ($ok) {
        Write-Host "  Verificacion OK: server-port = $($verify.'server-port'), master = $($verify.master)" -ForegroundColor Green
    } else {
        Write-Host ''
        Write-Host '  Contenido final del archivo:' -ForegroundColor Yellow
        Get-Content $settingsPath | ForEach-Object { Write-Host "    $_" }
    }

    # SP intenta monitorear Data/Platform/PluginsDev. Si no existe, escupe error en
    # skyrim-platform.log (no fatal, pero mejor evitarlo).
    $devDir = Join-Path $skyrimDir 'Data\Platform\PluginsDev'
    if (-not (Test-Path $devDir)) {
        New-Item -ItemType Directory -Path $devDir -Force | Out-Null
    }
}

# ---------- Main ----------

Write-Section 'Unitx SkyMP — Instalador'
Write-Host "Server: $ServerIp`:$ServerPort   master-key: $ServerMasterKey"

Write-Section '1. Detectando Skyrim Special Edition'
$skyrim = Resolve-SkyrimSEPath
if (-not $skyrim) { throw 'No se pudo determinar la carpeta de Skyrim SE.' }
Write-Host "  $skyrim" -ForegroundColor Green

Write-Section '2. Verificando SKSE64'
if (-not (Test-SKSE $skyrim)) { exit 1 }
Write-Host '  SKSE64 OK' -ForegroundColor Green

Write-Section '3. Localizando dist.zip del cliente'
$dist = Resolve-DistZip
Write-Host "  $dist" -ForegroundColor Green

Write-Section '4. Instalando cliente'
Expand-DistInto -zipPath $dist -skyrimDir $skyrim

Write-Section '5. Escribiendo configuración'
Write-ClientSettings -skyrimDir $skyrim

# Guardar el path detectado para que Play-UnitxSkyMP.ps1 no tenga que re-detectar.
$stateDir = Join-Path $env:LOCALAPPDATA 'UnitxSkyMP'
if (-not (Test-Path $stateDir)) { New-Item -ItemType Directory -Path $stateDir | Out-Null }
Set-Content -Path (Join-Path $stateDir 'skyrim-path.txt') -Value $skyrim -Encoding UTF8

Write-Section 'Instalación completa'
Write-Host "Para jugar:" -ForegroundColor Green
Write-Host "  1. Abre $skyrim" -ForegroundColor White
Write-Host '  2. Ejecuta skse64_loader.exe (NO el SkyrimSE.exe normal)' -ForegroundColor White
Write-Host ''

if ($LaunchAfterInstall) {
    $loader = Join-Path $skyrim 'skse64_loader.exe'
    Write-Host "Lanzando $loader ..." -ForegroundColor Cyan
    Start-Process -FilePath $loader -WorkingDirectory $skyrim
}

Stop-Transcript | Out-Null
Write-Host ''
Write-Host "Log guardado en: $script:LogPath" -ForegroundColor Cyan