aldroid

#!/bin/sh
#
# aldroid.sh
#
#  Created by Max Buck on 1/1/21.
#  Copyright © 2021 AppLovin Corporation. All rights reserved.
#
# This script is used to make APKs debuggable locally or pull an app, make it debuggable and push it pack to the device or pull/push files to an Android device
#
# Example Usage: ./aldroid.sh d com.applovin.enterprise.apps.demoapp
#

VERSION=0.4.2

usage() {
    cat <<EOF
usage: aldroid
  -h             Prints this information.
  -v             Prints version information.

usage: aldroid d[ebuggable] [options] <package_name>
Pulls the app, makes it debuggable and charlesable and reinstalls it. Will also handle obbs.
  --use-aapt2    Rebuild with aapt2.

usage: aldroid d[ebuggable] [options] --apk <apk_file> [splits]
Make an apk or a split apk debuggable and charlesable. Saves all inputs as <input>_debuggable.apk
  -o <output_directory> The directory to save the apks to.
  --use-aapt2    Rebuild with aapt2.
  --split        Indicates that this is a split apk and a list of splits follow the options.
  -i|--install   Install the apks after making them debuggable.
  --pm-install   Install the apk on the device using a pm install session instead of using 'adb install'.

usage: aldroid pull [options] <package_name>
Pull files for given package name.
  -o <output_directory> Directory in which to store the files. Defaults to /tmp/<package_name>
  --apk          Pull apk(s).
  --obb          Pull obb(s).

usage: aldroid b[uild] [options] <path_to_decoded_folder>
Rebuilds a decoded APK using apktool. The final apk will be named "[name of decoded apk]_rebuilt.apk"
  -o <output_directory> Directory in which to store the files. Defaults to current working directory.

usage: aldroid start <package_name>
Starts the app with the given package name on the connected device.

usage: aldroid kill <package_name>
Stops the app with the given package name on the connected device.

usage: aldroid sign <apk_file>
Signs the given (unsigned) APK in case of manual adjustment.

required tools:
adb - Android Platform Tools, usually located under ~/Library/Android/sdk/platform-tools/adb
apktool - Apktool, install via 'brew install apktool'
apksigner - Android Build Tools, usually located under ~/Library/Android/sdk/build-tools/<version>/apksigner
EOF
}

# Checks if debug keystore exists, otherwise create one
check_keystore() {
    if [ ! -f ~/.android/debug.keystore ]; then
        # Create ~/.android directory if it does not exist
        if [ ! -d ~/.android ]; then
            mkdir ~/.android
        fi

        # Generate a keystore and self-signed certificate:
        echo "No debug keystore found, creating a new one..."
        #   -v:         verbose mode enabled
        #   -keystore:  storage path
        #   -storepass: keystore password
        #   -alias:     unique alias
        #   -keypass:   key password
        #   -keyalg:    algorithm
        #   -keysize:   key size
        #   -validity:  validity in days
        keytool -genkey \
            -v \
            -keystore ~/.android/debug.keystore \
            -storepass android \
            -alias androiddebugkey \
            -keypass android \
            -keyalg RSA \
            -keysize 2048 \
            -validity 10000
    fi
}

# Check if apktool exists in path
check_apktool() {
    command -v apktool >/dev/null 2>&1 || {
        echo >&2 "ERROR: Apktool is not installed!"
        exit 1
    }
}

# Decompiles an apk with apktool
# First argument is the APK to decompile
# Second argument is optional and defines the path to the output folder (content will be overwritten if it exists) - defaults to /tmp/<apk_name_without_extensions>
decompile_apk() {
    local APK_IN=$1
    if [ -z "$APK_IN" ]; then
        echo >&2 "ERROR: No APK file specified to decompile!"
        exit 1
    fi

    # Strip APK file name of any extension
    local -r APK_NAME_WITH_EXT=$(basename "$APK_IN")
    local -r APK_NAME="${APK_NAME_WITH_EXT%.*}"

    local -r OUTPUT_DIRECTORY=${2:-/tmp/$APK_NAME}
    echo "Decompiling into $OUTPUT_DIRECTORY..."

    # Check that apktool is installed
    check_apktool

    # Decompiles the apk
    # -f: overwrite output directory
    # -s: skips source decompilation which is faster and source access is not required in 99% of cases
    # -o: explicitly set output directory
    apktool d -f -s -o "$OUTPUT_DIRECTORY" "$APK_IN"

    echo "Finished decompiling into ${OUTPUT_DIRECTORY}."

    return 0
}

# Rebuilds an apk with apktool
# First argument is the folder to rebuild
compile_apk() {
    local APK_IN=$1

    # TODO: check that input path exists
    # Check that apktool is installed
    check_apktool

    # Empty out internal frameworks in the output directory by force deleting the output directory
    apktool empty-framework-dir --force "$APK_IN"

    # Rebuild the apk. Reads $USE_AAPT2 which is set when this script is run with the --use-aapt2 flag
    # -f:          overwrite output APK if it already exists
    # --use-aapt2: Use the newer aapt2 to recompile resources which is sometimes required for a successful build
    # Will always output to APK_IN/dist/base.apk
    apktool b -f $USE_AAPT2 "$APK_IN"

    return 0
}

# Aligns and signs an APK
# First argument is the APK to resign
# Second argument is the output path for the resigned APK
sign_apk() {
    local APK_IN=$1

    # TODO: provide default for APK_OUT
    local APK_OUT=$2

    # Make sure the keystore exists
    check_keystore
    local debug_keystore=~/.android/debug.keystore

    # Optionally realign APK
    if [[ $ALIGN_OPT_SET == true ]]; then
        echo "Aligning $APK_IN to $APK_OUT..."

        # -f: overwrite output path if it exists
        #  4: defines byte-alignment boundaries; must be 4
        zipalign -f 4 "$APK_IN" "$APK_OUT"
    else
        cp "$APK_IN" "$APK_OUT"
    fi

    # Signs the APK
    echo "Signing $APK_OUT..."
    apksigner sign \
    --ks "$debug_keystore" \
    --ks-key-alias androiddebugkey \
    --ks-pass pass:android \
    --key-pass pass:android \
    "$APK_OUT"
}

# Pulls all APKs for a package name and saves an array with all pulled APK names to PULLED_APKS
# First argument is the package name for which to pull the APKs
# Second optional argument is the folder to save the APKs in - defaults to /tmp/<package_name>
pull_apks() {
    PULLED_APKS=()
    local PACKAGE_NAME=$1
    local OUTPUT_DIRECTORY=${2:-/tmp/$PACKAGE_NAME}

    echo "Pulling APK(s) for $PACKAGE_NAME into ${OUTPUT_DIRECTORY}..."

    # Ignore errors since our command is not guaranteed to succeed
    set +e

    # Gets a list of associated paths with the package name from pm (package manager). Packages are separated by newlines
    local apks;
    apks=$(adb shell pm path $PACKAGE_NAME)

    # Exit on any errors
    set -e

    # No APK found for package name
    if [[ -z $apks ]]; then
      echo "No APKs found for package name $PACKAGE_NAME. Aborting..."
      return 1
    fi

    # Create output directory if it does not exist
    if [ ! -d "$OUTPUT_DIRECTORY" ]; then
        mkdir "$OUTPUT_DIRECTORY"
    fi

    # Iterate over the list
    while IFS= read -r line; do
        # Each line is 'package:' followed by the absolute path to an APK
        # Remove first 8 characters (package:) from start of line
        local APK_REMOTE_PATH="${line:8}"
        APK_REMOTE_PATH=${APK_REMOTE_PATH//[$'\t\r\n']}

        # Pull APK from device and save it in the output directory
        echo "adb pull $APK_REMOTE_PATH $OUTPUT_DIRECTORY"
        adb pull "$APK_REMOTE_PATH" "$OUTPUT_DIRECTORY"
        echo "Pulled ${APK_REMOTE_PATH##*/} to $OUTPUT_DIRECTORY/${APK_REMOTE_PATH##*/}"

        # Add the saved APKs filename to the array
        APK_REMOTE_BASE_NAME="$(basename "$APK_REMOTE_PATH")"
        PULLED_APKS+=("$APK_REMOTE_BASE_NAME")
    done <<< "$apks"

    if [[ ${#PULLED_APKS[@]} -eq 0 ]]; then
      echo "No APKs pulled package name $PACKAGE_NAME. Aborting..."
      return 1
    fi

    return 0
}

# Updates a decompiled APK to make it debuggable and charlesable by adding android:debuggable="true" and updating/creating a network_security_config.xml
# First argument is the path to the decompiled APK
make_decompiled_debuggable() {
    local INPUT_DIRECTORY=$1

    # Create /res/xml directory for the APK if it does not exist
    if [ ! -d "$INPUT_DIRECTORY/res/xml" ]; then
        mkdir "$INPUT_DIRECTORY/res/xml"
    fi

    # Create network_security_config.xml or update it
    # The pub may have named their networkSecurityConfig.xml something different so we need to grab it
    local NSC_GREP=$(grep -E "<application.*?networkSecurityConfig=\".*?\".*?>" "$INPUT_DIRECTORY/AndroidManifest.xml")

    # Default name
    NSC_NAME="network_security_config"
    # Since networkSecurityConfig is not defined, set our default in the Android Manifest if it is not in the application tag
    if [[ -z $NSC_GREP ]]; then
        sed -E "s/(<application)/\1 android\:networkSecurityConfig=\"@xml\/$NSC_NAME\" /" "$INPUT_DIRECTORY/AndroidManifest.xml" > "$INPUT_DIRECTORY/AndroidManifest.xml.tmp"
        mv "$INPUT_DIRECTORY/AndroidManifest.xml.tmp" "$INPUT_DIRECTORY/AndroidManifest.xml"
    else
        # Make sure that the networkSecurityConfig has android: prefix
        local NSC_PREFIX_GREP=$(grep -E "<application.*android:networkSecurityConfig=\".*?\".*?>" "$INPUT_DIRECTORY/AndroidManifest.xml")

        # if the networkSecurityConfig is not prefixed with android: replace it
        if [[ -z $NSC_PREFIX_GREP ]]; then
            sed -E "s/networkSecurityConfig=/android:networkSecurityConfig=/g" "$INPUT_DIRECTORY/AndroidManifest.xml" > "$INPUT_DIRECTORY/AndroidManifest.xml.tmp"
            mv "$INPUT_DIRECTORY/AndroidManifest.xml.tmp" "$INPUT_DIRECTORY/AndroidManifest.xml"
        fi

        # networkSecurityConfig is defined, find the name via regex
        # First get a narrow match since ~= doesn't support lazy matching and grep doesn't support capture groups...
        NSC_NARROW_MATCH=$(grep -oE "networkSecurityConfig=\"@xml/.*?\"" <<< "$NSC_GREP")

        # Extract the networkSecurityConfig name from the narrow match
        REGEX="networkSecurityConfig=\"@xml\/(.*)\""
        if [[ $NSC_NARROW_MATCH =~ $REGEX ]]; then
            NSC_NAME=${BASH_REMATCH[1]}
            echo " Found networkSecurityConfig defined as: $NSC_NAME"
        fi
    fi

    # Check for usesCleartextTraffic in the Android Manifest
    # android:usesCleartextTraffic="true" allows cleartext traffic in the whole app but it is ignored when we add the network_security_config.xml
    # If that option is set add corresponding network_security_config.xml
    if grep "android:usesCleartextTraffic=\"true\"" "$INPUT_DIRECTORY/AndroidManifest.xml" || $OVERRIDE_NSC ; then
        # android:usesCleartextTraffic is true
        # Create a new network_security_config.xml with all cleartext traffic allowed (this will also overwrite any existing files)
        cat > "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml" << EOM
<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
<base-config cleartextTrafficPermitted="true">
</base-config>
<debug-overrides>
    <trust-anchors>
        <certificates src="user" />
    </trust-anchors>
</debug-overrides>
</network-security-config>
EOM
    fi

    # If the network_security_config.xml does not exist
    if [ ! -f "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml" ]; then
        # android:usesCleartextTraffic not true or not set
        # Create a new network_security_config.xml including only the debug override so we don't accidentally fix cleartext issues
        cat > "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml" << EOM
<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <debug-overrides>
        <trust-anchors>
            <certificates src="user" />
        </trust-anchors>
    </debug-overrides>
</network-security-config>
EOM
    # If the network_security_config.xml already exists and does not contain debug-overrides
    # TODO: technically there could be a case where the pub has overrides that do not include user certs, we should guard against that
    elif ! grep "debug-overrides" "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml"; then
        # Add debug-overrides to trust user certs
        # New lines are escaped for better readability
        sed -E "s/<\/network-security-config>/\
<debug-overrides>\
    <trust-anchors>\
        <certificates src=\"user\" \/>\
    <\/trust-anchors>\
<\/debug-overrides>\
<\/network-security-config>/" "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml" > "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml.tmp"
        mv "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml.tmp" "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml"
    # if it exists and has debug-overrides but does not allow user certificates
    # TODO: improve by handling all these cases more strictly, also maybe with just one pattern if possible
    elif ! grep '<certificates src=\"user\"' "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml"; then
        # use tr to translate newlines into carriage returns to have sed run on all lines
        tr '\n' '\r' < "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml" | sed -E 's|(<debug-overrides>.*<trust-anchors>)(\r *)<|\1\2<certificates src="user"/>\2<|' | tr '\r' '\n' > "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml.tmp"
        mv "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml.tmp" "$INPUT_DIRECTORY/res/xml/$NSC_NAME.xml"
    fi

    # Set debuggable in the Android Manifest
    # TODO: make sure it's correctly inside the application tag
    if grep -i "android:debuggable=\"false\"" "$INPUT_DIRECTORY/AndroidManifest.xml"; then
        sed -i "" "s|android:debuggable=\"false\"|android:debuggable=\"true\"|g" "$INPUT_DIRECTORY/AndroidManifest.xml"
    elif ! grep -i "android:debuggable" "$INPUT_DIRECTORY/AndroidManifest.xml"; then
        sed -E "s/(<application)/\1 android\:debuggable=\"true\" /" "$INPUT_DIRECTORY/AndroidManifest.xml" > "$INPUT_DIRECTORY/AndroidManifest.xml.tmp"
        mv "$INPUT_DIRECTORY/AndroidManifest.xml.tmp" "$INPUT_DIRECTORY/AndroidManifest.xml"
    fi

    # Set extractNativeLibs in the Android Manifest. Otherwise the app might crash when starting it on the device
    # TODO: make sure it's correctly inside the application tag
    if grep -i "extractNativeLibs=\"false\"" "$INPUT_DIRECTORY/AndroidManifest.xml"; then
        sed -i "" "s|android:extractNativeLibs=\"false\"|android:extractNativeLibs=\"true\"|g" "$INPUT_DIRECTORY/AndroidManifest.xml"
    fi

    # Remove android:localeConfig as it's currently causing issues when recompiling
    if grep -i "android:localeConfig" "$INPUT_DIRECTORY/AndroidManifest.xml"; then
        echo "removing android:localeConfig from AndroidManifest"
        sed -i "" "s|android:localeConfig=\"@xml\/locales_config\" ||g" "$INPUT_DIRECTORY/AndroidManifest.xml"
    fi
    # make locales_config compile by adding android schema
    # can't just delete it as it's referenced elsewhere
    if [ -f "$INPUT_DIRECTORY/res/xml/locales_config.xml" ]; then
        echo "Adding xmlns:android schema to locales_config"
        sed -i "" "s|<locale-config>|<locale-config xmlns:android=\"http:\/\/schemas.android.com\/apk\/res\/android\">|g" "$INPUT_DIRECTORY/res/xml/locales_config.xml"
    fi

    #remove meta data with @null values
    if grep -iE "<meta-data[^>]+android:resource=\"@null\"" "$INPUT_DIRECTORY/AndroidManifest.xml"; then
        sed -E -i "" "s|<meta-data[^>]+android:resource=\"@null\"/>||g" "$INPUT_DIRECTORY/AndroidManifest.xml"
    fi

    return 0
}

# Takes an apk and makes it debuggable and charlesable
# First argument is the APK file to make debuggable
# Second optional argument is the output file path for the debuggable APK - defaults to <APK_IN>_debuggable.apk
make_apk_debuggable() {
    local -r APK_IN=$1
    echo "Transforming $APK_IN to make it debuggable..."

    # Get filename without extensions
    local -r APK_NAME_WITH_EXT=$(basename "$APK_IN")
    local -r APK_NAME="${APK_NAME_WITH_EXT%.*}"

    # By default, output to /path/to/<APK_IN>_debuggable.apk
    local -r APK_OUT=${2-${APK_IN%\.apk}_debuggable.apk}
    echo "Saving output apk in ${APK_OUT}."

    # Make sure we decompile in /tmp so we don't create unnecessary folders
    local DECOMPIILE_DIRECTORY=${APK_IN%\.apk}
    if [[ "$APK_IN" != \/tmp\/* ]]; then
        DECOMPIILE_DIRECTORY="/tmp/${APK_NAME}"
    fi

    # Decompile the APK
    decompile_apk "$APK_IN" "$DECOMPIILE_DIRECTORY"

    # Extract package name for later use
    extract_package_name_from_manifest "$DECOMPIILE_DIRECTORY/AndroidManifest.xml"

    # Make it debuggable and charlesable
    make_decompiled_debuggable "$DECOMPIILE_DIRECTORY"

    # Rebuild it
    compile_apk "$DECOMPIILE_DIRECTORY"

    if [[ $USE_FALLBACK_DEBUGGABLE == true ]]; then
        if [[ -z $NSC_NAME ]]; then
            NSC_NAME="network_security_config"
        fi
        echo "Using $NSC_NAME as nsc name"

        echo "Using fallback to manually replace AndroidManifest and networkSecurityConfig."
        rm -rf "$DECOMPIILE_DIRECTORY/../uz"
        rm -rf "$DECOMPIILE_DIRECTORY/../uz0"
        unzip -q -d "$DECOMPIILE_DIRECTORY/../uz" "$DECOMPIILE_DIRECTORY/../base.apk"
        unzip -q -d "$DECOMPIILE_DIRECTORY/../uz0" "$DECOMPIILE_DIRECTORY/dist/${APK_NAME}.apk"
        cp "$DECOMPIILE_DIRECTORY/../uz0/AndroidManifest.xml" "$DECOMPIILE_DIRECTORY/../uz/AndroidManifest.xml"
        cp "$DECOMPIILE_DIRECTORY/../uz0/res/xml/$NSC_NAME.xml" "$DECOMPIILE_DIRECTORY/../uz/res/xml/$NSC_NAME.xml"
        pushd "$DECOMPIILE_DIRECTORY/../uz"
        zip -q -r -n resources.arsc ../test.apk .
        popd
        sign_apk "${DECOMPIILE_DIRECTORY}/../test.apk" "$APK_OUT"
    else
        # Align and sign it
        sign_apk "${DECOMPIILE_DIRECTORY}/dist/${APK_NAME}.apk" "$APK_OUT"
    fi
}

# Installs an APK or multiple APKs to a device with adb install / adb install-multiple
# Takes a list of APKs to install as arguments
install_apks() {
    # TODO: check for arguments

    local APKS=("$@")

    if [[ $USE_PM_INSTALL == true ]]; then
        CREATE_SESSION=$(adb shell pm install-create)
        REGEX="Success: created install session \[([0-9]+)\]"
        if [[ $CREATE_SESSION =~ $REGEX ]]; then
            SESSION_ID=${BASH_REMATCH[1]}
            echo "Started install session with session id: $SESSION_ID"
        else
            echo >&2 "Unable to start install session"
            exit 1
        fi

        for APK in "${APKS[@]}"
        do
            BASE_APK_NAME=$(basename "$APK")
            echo "Pushing $APK to device (/data/local/tmp/$BASE_APK_NAME)"
            adb push "$APK" "/data/local/tmp/$BASE_APK_NAME"

            echo "Adding $BASE_APK_NAME to install session"
            adb shell pm install-write $SESSION_ID "$BASE_APK_NAME" "/data/local/tmp/$BASE_APK_NAME"
        done

        echo "Finalizing install"
        adb shell pm install-commit $SESSION_ID

        return 0
    fi

    # Determine whether we have more then one APK and run adb install-multiple in that case
    local cmd="adb install"
    if [ ${#APKS[@]} -gt 1 ]; then
        cmd="adb install-multiple"
    fi

    # Install it on the device
    echo "Installing the following APK(s): ${APKS[@]}..."
    $cmd $INCREMENTAL ${APKS[@]}
}

# Uninstalls a package from a device
# The first argument is the package name to uninstall
uninstall_package() {
    # TODO: check for arguments

    echo "Uninstalling $1..."
    adb uninstall $1
}

# Pulls all apks for a package name, makes them debuggable and reinstalls them
# The first argument is the package name of the app
make_apk_debuggable_from_device() {
    local -r PACKAGE_NAME=$1
    local -r OUTPUT_DIRECTORY="/tmp/${PACKAGE_NAME}"

    echo "Making app $PACKAGE_NAME debuggable..."
    echo "Storing files in $OUTPUT_DIRECTORY"

    # Pull all APKs
    pull_apks "$PACKAGE_NAME" "$OUTPUT_DIRECTORY"

    # Pull all OBBs
    pull_obbs "$PACKAGE_NAME"

    local INDEX=1
    local APKS=()

    # Iterate over pulled APKs
    for APK in "${PULLED_APKS[@]}"
    do
        # Ignore empty or whitespace entries
        if [ -z "${APK// }" ]; then
            continue
        fi

        echo "Transforming $APK..."
        if [[ "$APK" == "base.apk" ]]; then
            # Base APK must be transformed to make it debuggable
            make_apk_debuggable "${OUTPUT_DIRECTORY}/${APK}" "${OUTPUT_DIRECTORY}/0.apk"
            # Save as 0.apk and add it to index 0 in the array
            APKS[0]="${OUTPUT_DIRECTORY}/0.apk"
        else
            # Split APKs just need to be resigned so the signature matches the base.apk
            sign_apk "${OUTPUT_DIRECTORY}/${APK}" "${OUTPUT_DIRECTORY}/${INDEX}.apk"
            # We number the starting at 1 so the base is always at the start of the array
            APKS[INDEX]="${OUTPUT_DIRECTORY}/${INDEX}.apk"
            ((INDEX++))
        fi
    done

    # Uninstall the app as we likely have a different signature now so reinstalling would throw an error
    uninstall_package "$PACKAGE_NAME"

    # Install our new APK(s)
    install_apks "${APKS[@]}"

    # Push back any OBBs we pulled so the game will run
    push_obbs "$PACKAGE_NAME"

    start_app "$PACKAGE_NAME"
}

# Pulls all OBBs associated with a package name and saves them in the array OBBS
# First argument is the package name for which to pull OBBs
# Second optional argument is the output directory to save the OBBs at - defaults to /tmp/<package name>
pull_obbs() {
    echo "Pulling OBB(s) for $1..."

    # Verify an argument was provided
    if [ -z $1 ]; then
        echo >&2 "ERROR: No package name provided to pull_obbs!"
        exit 1
    fi

    # Going to have to save the exit code. Declaring variable before we use it since local is itself something that generates an exit code
    local EXIT_CODE
    local TEMP_OBBS

    # Initialize as an empty array
    OBBS=()

    # Ignore errors since our ls command is not guaranteed to succeed
    set +e

    # OBBs are always saved at /sdcard/Android/obb/<package name> so we use ls to get a list of files there
    TEMP_OBBS=$(adb shell ls "/sdcard/Android/obb/$1")
    # Save exit code so we can use it to check if it worked
    EXIT_CODE=$?

    # Exit on any errors
    set -e

    # No OBBs found or no device connected
    if [[ $EXIT_CODE -ne 0 || -z $TEMP_OBBS ]]; then
        echo 'No OBBs found on device.'
        return 0
    fi

    # TODO: technically on some devices this will return code 0 and only a newline as output
    # We should stop this here instead of catching it later in the loop

    # Determine output directory
    local -r OUTPUT_DIRECTORY=${2-/tmp/$1}

    # Create output directory if it does not exist
    if [ ! -d "$OUTPUT_DIRECTORY" ]; then
        mkdir "$OUTPUT_DIRECTORY"
    fi

    # Iterate over all OBBs we found and pull them from the device
    for OBB in "$TEMP_OBBS"; do
        # In case there are other files there make sure the obb files end in .obb
        if [[ "${OBB: -4}" != ".obb" ]]; then
            continue
        fi

        adb pull "/sdcard/Android/obb/$1/$OBB" "$OUTPUT_DIRECTORY/$OBB"
        echo "Pulled $OBB into $OUTPUT_DIRECTORY/$OBB"
        OBBS+=$OBB
    done

    return 0
}

# Pushes OBBs back to the device
# Uses array stored in OBBS variable and assumes they reside in /tmp/<package name>
# First argument is the package name for which to push OBBs for
push_obbs() {
    # Verify an argument was provided
    if [ -z "$1" ]; then
        echo "No package name provided to push_obbs"
        exit 1
    fi

    echo "Pushing OBB(s)..."
    echo "$OBBS"

    # Safety for empty arrays as if it's empty we would push the entire folder
    if [[ ${#OBBS[@]} -eq 0 ]]; then
        echo "No OBBs to push"
        return 0
    fi

    # Iterate all OBBs on $OBBS and push them back to the device
    for OBB in "$OBBS"; do
        adb push "/tmp/$1/$OBB" "/sdcard/Android/obb/$1/$OBB"
    done

    return 0
}

# Starts an app on the device given a package name
# First argument is the package name to start
start_app() {
    # Verify an argument was provided
    if [ -z $1 ]; then
        echo "No package name provided to start_app"
        exit 1
    fi

    local PACKAGE_NAME=$1

    # Monkey is a tool to simulate user interaction. In this case it simulates a press on the app icon
    adb shell monkey -p "${PACKAGE_NAME}" -c android.intent.category.LAUNCHER 1 >/dev/null 2>&1
}

# Parses an AndroidManifest.xml to extract the package name
# First argument is the path to the AndroidManifest.xml
# Saves package name in EXTRACTED_PACKAGE_NAME
extract_package_name_from_manifest() {
    # Verify an argument was provided
    if [ -z $1 ]; then
        echo "No argument provided to extract_package_name_from_manifest"
        exit 1
    fi

    if [ ! -f $1 ]; then
        echo "$1 is not a path to a valid file"
        exit 1
    fi

    # Get AndroidManifest content
    local MANIFEST=$(cat "$1")
    local PACKAGE_NAME=

    # The manifest will include package inside the manifest tag
    # Ex: <manifest package="com.my.package.name">

    # Trim start until package="
    PACKAGE_NAME=${MANIFEST#*package=\"}
    # Trim everything after first "
    PACKAGE_NAME=${PACKAGE_NAME%%\"*}

    # Check if we have a valid package name
    # TODO: We only check if the string is not empty here but we should also guard against other cases like spaces in the string. Probably best to add a regex check like [a-zA-Z\.] to validate
    if [[ ! -z "$PACKAGE_NAME" ]]; then
        EXTRACTED_PACKAGE_NAME=$PACKAGE_NAME
        echo "Extracted package name: ${PACKAGE_NAME}"

    else
        echo "Unable to determine package name."
    fi
}

# Helper method for d[ebug] --apk to unclutter getopts
# Makes provided APK(s) debuggable and may install them incase -i/--install was set
# All splits are provided as a list of arguments
parse_make_apk_debuggable() {
    local BASE_APK_OUT=

    # Set default output path
    if [[ -z $OUT_OPT_ARG ]]; then
        BASE_APK_OUT=${BASE_APK_ARG%\.apk}_debuggable.apk
        make_apk_debuggable "$BASE_APK_ARG" "$BASE_APK_OUT"
    else
        # Make sure directory exists
        if [[ ! -d "$OUT_OPT_ARG" ]]; then
            mkdir "$OUT_OPT_ARG"
        fi

        # Because of --split and for consistency -o will always be a directory
        # Get output name
        local -r BASE_APK_NAME_WITH_EXT=$(basename "$BASE_APK_ARG")
        local -r BASE_APK_NAME=${BASE_APK_NAME_WITH_EXT%\.apk}_debuggable.apk
        BASE_APK_OUT="${OUT_OPT_ARG}/$BASE_APK_NAME"

        make_apk_debuggable "$BASE_APK_ARG" "$BASE_APK_OUT"
    fi

    # Save split locations so we can add them to the install command later
    SPLITS=()
    if [[ $SPLIT_OPT_SET == true ]]; then
        local -r OUTPUT_PATH=${OUT_OPT_ARG:-/tmp/$BASE_APK_ARG}
        for SPLIT in "$@"
        do
            local -r APK_NAME_WITH_EXT=$(basename "$SPLIT")
            local -r APK_NAME=${APK_NAME_WITH_EXT%\.apk}_debuggable.apk
            local -r split_out_path="${OUTPUT_PATH}/${APK_NAME}"

            # Add split to the array
            SPLITS+=("$split_out_path")

            sign_apk "${SPLIT}" "$split_out_path"
        done
    fi

    # Install the apks if -i/--install is set
    if [[ $INSTALL_OPT_SET == true ]]; then
        # Ignore errors since uninstall will fail if the app is not yet installed
        set +e

        # Uninstall the app
        uninstall_package $EXTRACTED_PACKAGE_NAME

        # Exit on any errors
        set -e

        # Install the app
        install_apks "$BASE_APK_OUT" "${SPLITS[@]}"

        # Start the app after it has been installed
        start_app "${EXTRACTED_PACKAGE_NAME}"
    fi
}

# Exit script after any errors
set -e

# Global variables for return values of pull_apks and pull_obbs and extract_package_name_from_manifest
PULLED_APKS=()
OBBS=()
EXTRACTED_PACKAGE_NAME=

# Parse basic options
while getopts "h?v" opt; do
    case "$opt" in
        v)
            echo "$VERSION"
            exit 0
            ;;
        h|\?)
            usage
            exit 0
            ;;
    esac
done
# End option parsing by dropping all parsed arguments
shift $((OPTIND-1))

# Save subcommand and remove it from list of arguments
SUBCOMMAND=$1
shift

# Initialize option argument variables
BASE_APK_ARG=
OUT_OPT_ARG=
APK_OPT_SET=false
OBB_OPT_SET=false
SPLIT_OPT_SET=false
INSTALL_OPT_SET=false
USE_AAPT2='--use-aapt2'
ALIGN_OPT_SET=false
OVERRIDE_NSC=false
USE_PM_INSTALL=false
INCREMENTAL='--no-incremental'
USE_FALLBACK_DEBUGGABLE=false

# Parse options for subcommand
while getopts "i-:o:" opt; do
    case "$opt" in
    h|\?)
        usage
        exit 0
        ;;
    v)
        echo "$0 - version: $VERSION"
        exit 0
        ;;
    o)
        OUT_OPT_ARG="${OPTARG}"
        ;;
    i)
        INSTALL_OPT_SET=true
        ;;
    -)
        case "${OPTARG}" in
            apk)
                APK_OPT_SET=true
                if [[ $SUBCOMMAND == "d" || $SUBCOMMAND == "debuggable" || $SUBCOMMAND == "install" ]]; then
                    BASE_APK_ARG="${!OPTIND}";
                    OPTIND=$(( $OPTIND + 1 ))

                    # Exit if BASE_APK_ARG does not exist
                    if [[ ! -f $BASE_APK_ARG ]]; then
                        echo "ERROR: Input APK $BASE_APK_ARG does not exist."
                        exit 1
                    fi
                fi
                ;;
            obb)
                OBB_OPT_SET=true
                ;;
            split)
                SPLIT_OPT_SET=true
                ;;
            use-aapt)
                USE_AAPT2=''
                ;;
            use-aapt2)
                USE_AAPT2='--use-aapt2'
                ;;
            no-incremental)
                INCREMENTAL='--no-incremental'
                ;;
            incremental)
                INCREMENTAL=''
                ;;
            install)
                INSTALL_OPT_SET=true
                ;;
            align)
                ALIGN_OPT_SET=true
                ;;
            override-nsc)
                OVERRIDE_NSC=true
                ;;
            pm-install)
                USE_PM_INSTALL=true
                ;;
            fallback)
                USE_FALLBACK_DEBUGGABLE=true
                ;;
            *) # Others - print usage
                usage
                exit 1
                ;;
        esac
        ;;
    esac
done
# End option parsing by dropping all parsed arguments
shift $((OPTIND-1))

# We require a subcommand to be provided as the first argument
if [[ -z $SUBCOMMAND ]]; then
    usage
    exit 1
fi

echo "aldroid v$VERSION"

case $SUBCOMMAND in
    d|debuggable)
        if [[ $APK_OPT_SET == true ]]; then
            echo "Making $BASE_APK_ARG debuggable..."
            parse_make_apk_debuggable
        else
            make_apk_debuggable_from_device "$1"
        fi
        exit 0
        ;;
    p|pull)
        # Verify an argument was provided
        if [ -z $1 ]; then
            echo >&2 "ERROR: No package name provided to pull!"
            exit 1
        fi

        # If --apk was set, pull APKs
        if [[ $APK_OPT_SET == true ]]; then
            pull_apks "$1" "$OUT_OPT_ARG"
        fi

        # If --obb was set, pull OBBs
        if [[ $OBB_OPT_SET == true ]]; then
            pull_obbs "$1" "$OUT_OPT_ARG"
        fi

        exit 0
        ;;
    s|start)
        # Verify an argument was provided
        if [ -z $1 ]; then
            echo >&2 "ERROR: No package name provided to start!"
            exit 1
        fi

        start_app $1
        exit 0
        ;;
    sign)
        # verify input apk was provided
        if [ -z $1 ]; then
            echo >&2 "ERROR: please provide input apk!"
            exit 1
        fi

        # Strip APK file name of any extension
        APK_NAME_WITH_EXT=$(basename "$1")
        APK_NAME="${APK_NAME_WITH_EXT%.*}"

        # Set output paths
        # defaults to just put it in the current working directory
        APK_OUT="${APK_NAME}_resigned.apk"

        sign_apk "$1" "$APK_OUT"
        echo "Signed APK at $APK_OUT"
        ;;
# TODO: support an install action which pushes obbs too?
#    install)
#        ;;
# TODO: support pushing a set of obbs with a given package name, to do that push_obbs should accept an optional parameter or the whole obb code needs to be rewritten to no longer need hard coded path for location
#    push-obb)
#        push_obbs $2
#        ;;
    b|build)
        # verify path was provided
        if [ -z $1 ]; then
            echo >&2 "ERROR: path to folder to build provided!"
            exit 1
        fi

        # Extract name for APK from apktool.yml
        APK_NAME=$(grep "apkFileName: .*.apk" "$1/apktool.yml")
        REGEX="apkFileName: (.*).apk"
        if [[ $APK_NAME =~ $REGEX ]]; then
            APK_NAME=${BASH_REMATCH[1]}
        else
            echo >&2 "ERROR: Unable to get name from apktool.yml!"
            exit 1
        fi

        # Set output paths
        if [[ -z $OUT_OPT_ARG ]]; then
            # default to just put it in the current working directory
            APK_OUT="${APK_NAME}_rebuilt.apk"
        else
            # Make sure directory exists
            if [[ ! -d "$OUT_OPT_ARG" ]]; then
                mkdir "$OUT_OPT_ARG"
            fi

            # Because of --split and for consistency -o will always be a directory. Combine with name of decoded APK
            #TODO maybe we want to support a different argument here to be able to set a specific apk name
            # Get output name
            APK_OUT="${OUT_OPT_ARG}/${APK_NAME}.apk"
        fi


        # Rebuild it
        compile_apk "$1"

        # Align and sign it
        sign_apk "$1/dist/${APK_NAME}.apk" "$APK_OUT"

        # TODO support specifying other APKs that also need to be installed and auto-pickup of numbered apks (ie 1.apk 2.apk etc)
        if [[ $INSTALL_OPT_SET == true ]]; then
            install_apks "$APK_OUT"
        fi

        echo "Output APK at $APK_OUT"
        ;;

    k|kill)
        adb shell am force-stop $1
        ;;

    *) # Undefined - print usage
        usage
        exit 1
        ;;
esac