#!/bin/bash
# Builds Podlite without the Android SDK or Gradle, one APK per Android level (same package and key):
#   build/Podlite.apk        Android 2.2 and later (Galaxy Mini)   src + platform/api8,  against android-8
#   build/Podlite-api16.apk  Android 4.1 and later (Xperia J...)   src + platform/api16 + ExoPlayer, against android-16
# Each: aapt2 (resources; api16 overlays platform/api16/res) -> javac (Java 8 bytecode) -> then
#   api8:  Dalvik 2.x link check -> dx (dex 035)
#   api16: R8 (shrinks ExoPlayer and Guava, desugars Java 8, dex 035 for Android 4.1)
# -> signapk.py (v1 / SHA-1 in the classic SignApk format, plus zipalign; Android <= 4.2 rejects jarsigner's).
# versionCode = the manifest's x 100 + the level, so a phone that moves up to Android 4.1 gets the newer build as an update.
# Toolchain (TOOLS, default ~/android-toolchain) from Plexamp Lite's tools/setup_toolchain.sh, plus tools/fetch_exoplayer.sh,
# the android-16 jar and R8 (d8.jar from build-tools 34) for api16.
#   ./build.sh            both
#   ./build.sh 16         one level
set -euo pipefail
cd "$(dirname "$0")"
T=${TOOLS:-$HOME/android-toolchain}
BC_SRC=$T/bcsrc                      # Bouncy Castle renamed to com.minamp.bc
EXO=$T/exoplayer-2.18.7
R8=${R8:-$T/calendar-tools/d8.jar}   # build-tools' d8.jar holds R8 too
PY=${PY:-$T/venv/bin/python}         # signapk.py needs the cryptography package
[ -x "$PY" ] || PY=python3
KS=${KEYSTORE:-miniabs.keystore}     # JKS, password and alias "miniabs": keep it, updates only install over the same key
LEVELS=${*:-8 16}
# a JDK 11+ (R8 needs it): the macOS java stub answers "javac" but can't run it
if ! javac -version >/dev/null 2>&1 || javac -version 2>&1 | grep -q '1\.8'; then
  for j in "${JAVA_HOME:-}" /opt/homebrew/opt/openjdk@17 /opt/homebrew/opt/openjdk $(ls -d "$HOME"/tools/jdk-17* 2>/dev/null); do
    if [ -n "$j" ] && [ -x "$j/bin/javac" ]; then export JAVA_HOME=$j PATH=$j/bin:$PATH; break; fi
  done
fi

mkdir -p build
# signapk.py reads PKCS#12: convert the JKS key into build/ for this run (the original stays as it is)
P12=build/signing.p12
rm -f $P12
keytool -importkeystore -srckeystore "$KS" -srcstoretype JKS -srcstorepass ${KEYPASS:-miniabs} -srcalias miniabs \
  -destkeystore $P12 -deststoretype PKCS12 -deststorepass ${KEYPASS:-miniabs} -destkeypass ${KEYPASS:-miniabs} \
  -noprompt >/dev/null 2>&1
trap 'rm -f build/signing.p12' EXIT

CODE=$(sed -n 's/.*android:versionCode="\([0-9]*\)".*/\1/p' AndroidManifest.xml)

for API in $LEVELS; do
  case $API in
    8)  TARGET=10; APK=build/Podlite.apk ;;
    16) TARGET=16; APK=build/Podlite-api16.apk
        [ -f "$EXO/exoplayer-core.jar" ] || { echo "no ExoPlayer in $EXO: run tools/fetch_exoplayer.sh"; exit 1; }
        [ -f "$R8" ] || { echo "no R8 at $R8 (build-tools 34's lib/d8.jar): set R8="; exit 1; } ;;
    *)  echo "no such level: $API (8 or 16)"; exit 1 ;;
  esac
  ANDROID_JAR=$T/platforms/android-$API/android.jar
  OUT=build/api$API
  echo "== Android level $API -> $APK (versionCode $((CODE * 100 + API)))"
  rm -rf $OUT && mkdir -p $OUT/res $OUT/gen $OUT/classes

  # this level's manifest; Android 3.2+ also counts a rotation as a screen size change; Holo settings on 4.1
  sed -e "s/android:minSdkVersion=\"[0-9]*\"/android:minSdkVersion=\"$API\"/" \
      -e "s/android:targetSdkVersion=\"[0-9]*\"/android:targetSdkVersion=\"$TARGET\"/" \
      $( [ $API -ge 13 ] && echo '-e s/keyboardHidden|orientation"/keyboardHidden|orientation|screenSize"/' ) \
      $( [ $API -ge 14 ] && echo '-e s#android:theme="@android:style/Theme"#android:theme="@android:style/Theme.Holo"#' ) \
      AndroidManifest.xml > $OUT/AndroidManifest.xml

  $T/aapt2 compile --dir res -o $OUT/res/compiled.zip
  OVERLAY=
  if [ -d platform/api$API/res ]; then
    $T/aapt2 compile --dir platform/api$API/res -o $OUT/res/overlay.zip
    OVERLAY="-R $OUT/res/overlay.zip"
  fi
  $T/aapt2 link -o $OUT/base.apk -I $ANDROID_JAR --manifest $OUT/AndroidManifest.xml \
    --java $OUT/gen -A assets --version-code $((CODE * 100 + API)) --replace-version \
    --no-version-vectors $OUT/res/compiled.zip $OVERLAY

  LIBS=
  [ $API -ge 16 ] && LIBS=$(ls $EXO/*.jar | tr '\n' ':')
  find src platform/api$API $OUT/gen -name '*.java' > $OUT/sources.txt
  javac -nowarn -Xlint:-options -source 8 -target 8 -encoding UTF-8 -g:source,lines \
    -bootclasspath $ANDROID_JAR -classpath "$LIBS" -sourcepath "src:platform/api$API:$BC_SRC:$OUT/gen" \
    -d $OUT/classes @$OUT/sources.txt 2>&1 | grep -v -E '^Picked up|^Note:|^warning: Cannot find annotation|^  reason: class file for|^[0-9]+ warnings?$' || true
  test -f $OUT/classes/com/miniabs/HomeActivity.class

  if [ $API -lt 11 ]; then
    echo "-- Dalvik 2.x link check"
    python3 tools/scan_dalvik.py $OUT/classes $ANDROID_JAR > $OUT/dalvik-scan.txt
    if ! grep -q "^total patterns: 0$" $OUT/dalvik-scan.txt; then
      cat $OUT/dalvik-scan.txt; echo "Calls Android 2.x can't link (see above): fix before shipping"; exit 1
    fi
    java -Xmx2g -jar $T/dx.jar --dex --output=$OUT/classes.dex $OUT/classes 2>&1 | grep -v '^Picked up' || true
  else
    echo "-- R8"
    (cd $OUT/classes && zip -q -r ../app.jar .)
    PGCONF=$(for f in tools/r8-rules.pro $EXO/*.pro; do printf -- '--pg-conf %s ' "$f"; done)
    java -Xmx2g -cp "$R8" com.android.tools.r8.R8 --release --min-api $API --lib $ANDROID_JAR \
      --map-diagnostics info none --output $OUT $PGCONF $OUT/app.jar $EXO/*.jar 2>&1 \
      | grep -v -E '^Picked up|META-INF' || true
    test -f $OUT/classes.dex
    # one dex only: Android 4.1 can't load a second without a multidex library
    if [ -f $OUT/classes2.dex ]; then echo "R8 made more than one dex file (over 64K methods)"; exit 1; fi
  fi

  cp $OUT/base.apk $OUT/unsigned.apk
  (cd $OUT && zip -q unsigned.apk classes.dex)
  $PY tools/signapk.py $P12 ${KEYPASS:-miniabs} $OUT/unsigned.apk $APK
  python3 tools/check_dex.py $APK
  ls -l $APK
done