# decompile_kaiyu.ps1 - Download jadx, pull KAIYU APK, decompile to Java source
#
# Run from D:\HereMyHope\hh-bt-controller:
#   powershell -ExecutionPolicy Bypass -File sniffer/decompile_kaiyu.ps1
#
# Automatically picks jadx version based on your Java:
#   Java 8  -> jadx 1.2.0 (last version supporting Java 8)
#   Java 11+ -> jadx 1.5.0

$BaseDir   = "D:\Claude\HH-BT-Controller\decompile"
$JadxDir   = "$BaseDir\jadx"
$JadxZip   = "$BaseDir\jadx.zip"
$ApkPath   = "$BaseDir\kaiyu.apk"
$OutputDir = "$BaseDir\kaiyu_src"
$Adb       = if (Test-Path "D:\platform-tools\adb.exe") { "D:\platform-tools\adb.exe" } else { "adb" }
$Pkg       = "com.qunyu.kaiyu"

New-Item -ItemType Directory -Force -Path $BaseDir | Out-Null

Write-Host "============================================" -ForegroundColor Cyan
Write-Host "  KAIYU APK Decompiler" -ForegroundColor Cyan
Write-Host "============================================" -ForegroundColor Cyan

# ── Detect Java version ───────────────────────────────────────────────────────
Write-Host "`nDetecting Java version..." -ForegroundColor Gray
$javaVer = 8
try {
    $javaOut = & java -version 2>&1 | Select-Object -First 1
    Write-Host "  $javaOut" -ForegroundColor Gray
    if ($javaOut -match '"(\d+)[\._]') {
        $major = [int]$Matches[1]
        # Java 8 reports as "1.8.x", Java 11+ reports as "11.x"
        $javaVer = if ($major -eq 1) {
            [int]($javaOut -replace '.*"1\.(\d+).*','$1')
        } else { $major }
    }
} catch { Write-Host "  Could not detect Java version, assuming Java 8" -ForegroundColor Yellow }

Write-Host "  Java major version: $javaVer" -ForegroundColor Gray

# Pick jadx version accordingly
if ($javaVer -ge 11) {
    $jadxVersion = "1.5.0"
    $jadxUrl = "https://github.com/skylot/jadx/releases/download/v1.5.0/jadx-1.5.0.zip"
    Write-Host "  Using jadx 1.5.0 (Java 11+ detected)" -ForegroundColor Gray
} else {
    $jadxVersion = "1.2.0"
    $jadxUrl = "https://github.com/skylot/jadx/releases/download/v1.2.0/jadx-1.2.0.zip"
    Write-Host "  Using jadx 1.2.0 (Java 8 detected - last version supporting Java 8)" -ForegroundColor Yellow
}

# ── 1. Download jadx ──────────────────────────────────────────────────────────
$jadxBat = Get-ChildItem -Path $JadxDir -Recurse -Filter "jadx.bat" -ErrorAction SilentlyContinue |
           Select-Object -First 1 -ExpandProperty FullName

if (-not $jadxBat) {
    Write-Host "`n[1/4] Downloading jadx $jadxVersion..." -ForegroundColor Yellow
    try {
        Invoke-WebRequest -Uri $jadxUrl -OutFile $JadxZip -UseBasicParsing
        $sizeMB = [math]::Round((Get-Item $JadxZip).Length / 1MB, 1)
        Write-Host "      Downloaded ($sizeMB MB)"
        Write-Host "      Extracting..."
        Expand-Archive -Path $JadxZip -DestinationPath $JadxDir -Force
        Remove-Item $JadxZip -Force
        $jadxBat = Get-ChildItem -Path $JadxDir -Recurse -Filter "jadx.bat" |
                   Select-Object -First 1 -ExpandProperty FullName
        Write-Host "      jadx ready: $jadxBat" -ForegroundColor Green
    } catch {
        Write-Host "[ERROR] Download failed: $_" -ForegroundColor Red
        Write-Host "  Download manually: $jadxUrl"
        Write-Host "  Extract to: $JadxDir"
        Read-Host; exit 1
    }
} else {
    Write-Host "`n[1/4] jadx already present: $jadxBat" -ForegroundColor Green
}

if (-not $jadxBat) {
    Write-Host "[ERROR] jadx.bat not found after extraction." -ForegroundColor Red
    Read-Host; exit 1
}

# ── 2. Pull APK ───────────────────────────────────────────────────────────────
if (-not (Test-Path $ApkPath) -or (Get-Item $ApkPath).Length -lt 1MB) {
    Write-Host "`n[2/4] Pulling APK from phone..." -ForegroundColor Yellow
    $pmOut = & $Adb shell "pm path $Pkg" 2>&1
    if ($pmOut -notmatch "package:") {
        Write-Host "[ERROR] KAIYU not found on device." -ForegroundColor Red
        & $Adb devices; Read-Host; exit 1
    }
    $apkOnDevice = ($pmOut -split "`n" | Where-Object { $_ -match "package:" } |
                    Select-Object -First 1).Replace("package:", "").Trim()
    Write-Host "      Device path: $apkOnDevice"
    & $Adb pull $apkOnDevice $ApkPath
    if (-not (Test-Path $ApkPath) -or (Get-Item $ApkPath).Length -lt 1MB) {
        & $Adb shell "cp '$apkOnDevice' /sdcard/kaiyu_tmp.apk"
        & $Adb pull /sdcard/kaiyu_tmp.apk $ApkPath
        & $Adb shell "rm /sdcard/kaiyu_tmp.apk" 2>&1 | Out-Null
    }
    if (-not (Test-Path $ApkPath)) {
        Write-Host "[ERROR] APK pull failed." -ForegroundColor Red; Read-Host; exit 1
    }
    Write-Host "      APK: $([math]::Round((Get-Item $ApkPath).Length/1MB,1)) MB" -ForegroundColor Green
} else {
    Write-Host "`n[2/4] APK already pulled ($([math]::Round((Get-Item $ApkPath).Length/1MB,1)) MB) -- skipping." -ForegroundColor Green
}

# ── 3. Decompile ──────────────────────────────────────────────────────────────
Write-Host "`n[3/4] Decompiling with jadx $jadxVersion (1-3 min)..." -ForegroundColor Yellow
if (Test-Path $OutputDir) {
    Write-Host "      Removing previous output..."
    Remove-Item -Recurse -Force $OutputDir
}

& $jadxBat --deobf --show-bad-code -d $OutputDir $ApkPath

$count = (Get-ChildItem -Recurse -Filter "*.java" -Path $OutputDir -ErrorAction SilentlyContinue).Count
if ($count -eq 0) {
    Write-Host "[ERROR] No Java files produced. Check jadx output above." -ForegroundColor Red
    Read-Host; exit 1
}
Write-Host "      $count Java files decompiled." -ForegroundColor Green

# ── 4. Analyse ────────────────────────────────────────────────────────────────
Write-Host "`n[4/4] Analysing for BLE protocol..." -ForegroundColor Yellow

$analysePy = @(
    "sniffer\analyse_jadx.py",
    "D:\Claude\HH-BT-Controller\sniffer\analyse_jadx.py"
) | Where-Object { Test-Path $_ } | Select-Object -First 1

if ($analysePy) {
    python $analysePy --src $OutputDir
} else {
    Write-Host "  analyse_jadx.py not found, run manually:"
    Write-Host "  python sniffer\analyse_jadx.py --src `"$OutputDir`""
}

Write-Host "`n============================================" -ForegroundColor Green
Write-Host "  Done!  Source at: $OutputDir" -ForegroundColor Green
Write-Host "  Open in VS Code: code `"$OutputDir`"" -ForegroundColor Green
Write-Host "============================================" -ForegroundColor Green
Read-Host "`nPress Enter to exit"