#!/usr/bin/env bash
REPO="NohamR/RMHook-Android"
WORKDIR="/tmp/rmhook"

set -euo pipefail

# --- Check dependencies ---
echo "[INFO] Checking dependencies..."
MISSING=()
for cmd in adb apktool keytool; do
    command -v "$cmd" >/dev/null 2>&1 || MISSING+=("$cmd")
done
# Check Android SDK build-tools (zipalign + apksigner)
SDK_ROOT="${ANDROID_SDK_ROOT:-$HOME/Library/Android/sdk}"
BUILD_TOOLS="$(find "$SDK_ROOT/build-tools" -maxdepth 1 -type d 2>/dev/null | sort -V | tail -1)"
if [ -z "$BUILD_TOOLS" ] || [ ! -d "$BUILD_TOOLS" ]; then
    MISSING+=("Android SDK build-tools (zipalign, apksigner)")
fi
if [ ${#MISSING[@]} -gt 0 ]; then
    echo "❌ Missing required tools:"
    for m in "${MISSING[@]}"; do echo "   - $m"; done
    echo ""
    echo "Install with:"
    echo "  brew install apktool android-platform-tools"
    echo "  # Android SDK build-tools via Android Studio SDK Manager"
    exit 1
fi
export ANDROID_SDK_BUILD_TOOLS="$BUILD_TOOLS"

# --- Setup workspace ---
echo "[INFO] Setting up workspace..."
rm -rf "$WORKDIR"
mkdir -p "$WORKDIR/build" "$WORKDIR/libs" "$WORKDIR/config" "$WORKDIR/output"

# --- Download .so files from releases ---
echo "[INFO] Downloading librmhook.so..."
curl -sL \
  -o "$WORKDIR/build/librmhook.so" \
  "https://github.com/$REPO/releases/latest/download/librmhook.so"

echo "[INFO] Downloading libshadowhook_nothing.so..."
curl -sL \
  -o "$WORKDIR/libs/libshadowhook_nothing.so" \
  "https://github.com/$REPO/releases/latest/download/libshadowhook_nothing.so"

# --- Pull APK splits from device ---
APK_DIR="$HOME/reMarkable/app"
mkdir -p "$APK_DIR"

echo "[INFO] Detecting reMarkable app on device..."
PKG_PATHS="$(adb shell pm path com.remarkable.mobile 2>/dev/null || true)"
if [ -z "$PKG_PATHS" ]; then
    echo "❌ reMarkable app not found on device. Install it from the Play Store first."
    exit 1
fi

echo "[INFO] Pulling APK splits..."
while IFS= read -r line; do
    APK_PATH="${line#package:}"
    APK_NAME="$(basename "$APK_PATH")"
    echo "   Pulling $APK_NAME..."
    adb pull "$APK_PATH" "$APK_DIR/$APK_NAME" 2>/dev/null
done <<< "$PKG_PATHS"

if [ ! -f "$APK_DIR/base.apk" ]; then
    echo "❌ Failed to pull base.apk"
    exit 1
fi

# --- Inject RMHook into APKs ---
APK_DIR_INJECT="$APK_DIR"
BUILD_DIR="$WORKDIR/build"
OUTPUT_DIR="$WORKDIR/output"
LIBS_DIR="$WORKDIR/libs"
KEYSTORE="$WORKDIR/config/rmhook.keystore"
KEYSTORE_PASS="rmhook"
KEY_ALIAS="rmhook"
ZIPALIGN="$BUILD_TOOLS/zipalign"
APKSIGNER="$BUILD_TOOLS/apksigner"

# Portable in-place sed (GNU vs BSD/macOS)
sed_inplace() {
    if sed --version >/dev/null 2>&1; then
        sed -i "$@"
    else
        sed -i '' "$@"
    fi
}

echo ""
echo "[INFO] Injecting RMHook into reMarkable APKs..."

rm -rf "$OUTPUT_DIR"
mkdir -p "$OUTPUT_DIR"
rm -rf "$BUILD_DIR/base" "$BUILD_DIR/split_arm64" "$BUILD_DIR/split_xxhdpi"
rm -f "$BUILD_DIR"/*.apk

# --- Step 1: Decompile and patch base.apk (smali injection) ---
echo "[1/4] Patching base.apk (smali injection)..."
apktool d -r "$APK_DIR_INJECT/base.apk" -o "$BUILD_DIR/base" -f

MAIN_SMALI="$BUILD_DIR/base/smali/com/remarkable/mobile/MainActivity.smali"
if [ ! -f "$MAIN_SMALI" ]; then
    echo "❌ MainActivity.smali not found"
    exit 1
fi

sed_inplace '/.method static constructor <clinit>()V/{
n
/.locals/{
a\
\
    const-string v0, "rmhook"\
\
    invoke-static {v0}, Ljava/lang/System;->loadLibrary(Ljava/lang/String;)V
}
}' "$MAIN_SMALI"

if ! grep -q 'invoke-static {v0}, Ljava/lang/System;->loadLibrary' "$MAIN_SMALI"; then
    echo "❌ Failed to inject loadLibrary(\"rmhook\") into MainActivity.smali"
    exit 1
fi

echo "✅ Injected System.loadLibrary(\"rmhook\") into MainActivity.<clinit>"
apktool b "$BUILD_DIR/base" -o "$BUILD_DIR/base_patched.apk"

# --- Step 2: Inject libraries into arm64 split ---
echo "[2/4] Injecting ShadowHook libraries into arm64 split..."
SPLIT_ARM64="$APK_DIR_INJECT/split_config.arm64_v8a.apk"
if [ ! -f "$SPLIT_ARM64" ]; then
    echo "❌ $SPLIT_ARM64 not found"
    exit 1
fi

mkdir -p "$BUILD_DIR/split_arm64"
unzip -q "$SPLIT_ARM64" -d "$BUILD_DIR/split_arm64"
cp "$BUILD_DIR/librmhook.so" "$BUILD_DIR/split_arm64/lib/arm64-v8a/"
cp "$LIBS_DIR/libshadowhook_nothing.so" "$BUILD_DIR/split_arm64/lib/arm64-v8a/"
rm -rf "$BUILD_DIR/split_arm64/META-INF"
(cd "$BUILD_DIR/split_arm64" && zip -q -r -0 "$BUILD_DIR/split_arm64_raw.apk" .)

# --- Step 3: Align APKs ---
echo "[3/4] Aligning APKs..."
"$ZIPALIGN" -p -f 4 "$BUILD_DIR/base_patched.apk" "$BUILD_DIR/base_aligned.apk"
"$ZIPALIGN" -p -f 4 "$BUILD_DIR/split_arm64_raw.apk" "$BUILD_DIR/split_arm64_aligned.apk"

SPLIT_XXHDPI="$APK_DIR_INJECT/split_config.xxhdpi.apk"
if [ -f "$SPLIT_XXHDPI" ]; then
    mkdir -p "$BUILD_DIR/split_xxhdpi"
    unzip -q "$SPLIT_XXHDPI" -d "$BUILD_DIR/split_xxhdpi"
    rm -rf "$BUILD_DIR/split_xxhdpi/META-INF"
    (cd "$BUILD_DIR/split_xxhdpi" && zip -q -r -0 "$BUILD_DIR/split_xxhdpi_raw.apk" .)
    "$ZIPALIGN" -p -f 4 "$BUILD_DIR/split_xxhdpi_raw.apk" "$BUILD_DIR/split_xxhdpi_aligned.apk"
fi

# --- Step 4: Sign all APKs ---
echo "[4/4] Signing APKs..."

if [ ! -f "$KEYSTORE" ]; then
    mkdir -p "$(dirname "$KEYSTORE")"
    echo "🔑 Generating signing keystore..."
    keytool -genkeypair -v \
        -keystore "$KEYSTORE" \
        -alias "$KEY_ALIAS" \
        -keyalg RSA -keysize 2048 \
        -validity 10000 \
        -storepass "$KEYSTORE_PASS" \
        -keypass "$KEYSTORE_PASS" \
        -dname "CN=RMHook, OU=Dev, O=RMHook, L=Unknown, ST=Unknown, C=US" \
        2>/dev/null
fi

sign_apk() {
    local input="$1"
    local output="$2"
    "$APKSIGNER" sign \
        --ks "$KEYSTORE" \
        --ks-pass "pass:$KEYSTORE_PASS" \
        --ks-key-alias "$KEY_ALIAS" \
        --key-pass "pass:$KEYSTORE_PASS" \
        --out "$output" \
        "$input"
}

sign_apk "$BUILD_DIR/base_aligned.apk" "$OUTPUT_DIR/base.apk"
sign_apk "$BUILD_DIR/split_arm64_aligned.apk" "$OUTPUT_DIR/split_config.arm64_v8a.apk"
if [ -f "$BUILD_DIR/split_xxhdpi_aligned.apk" ]; then
    sign_apk "$BUILD_DIR/split_xxhdpi_aligned.apk" "$OUTPUT_DIR/split_config.xxhdpi.apk"
fi

echo "✅ Injection successful!"

# --- Install ---
echo "[INFO] Installing patched APKs..."
adb uninstall com.remarkable.mobile 2>/dev/null || true
adb install-multiple --no-streaming "$WORKDIR/output/base.apk" "$WORKDIR/output/split_config.arm64_v8a.apk" "$WORKDIR/output/split_config.xxhdpi.apk"

echo ""
echo "✅ Done! RMHook is installed on your reMarkable."
echo ""
echo "📋 Next steps:"
echo "   1. Open the reMarkable app"
echo "   2. Configure your rmfakecloud host and port"
echo ""
echo "🔍 To debug:"
echo "   adb logcat -s 'RMHook:*'"