#!/usr/bin/env bash
set -Eeuo pipefail

APP_NAME="e-SUN"
MODULE="app"
API_LEVEL="35"
BUILD_TOOLS_VERSION="35.0.0"
DIST_DIR="dist"
COMMIT_MSG_FILE="commit-message.txt"

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$ROOT_DIR"

export GRADLE_OPTS="${GRADLE_OPTS:-} -Dorg.gradle.daemon=false"

usage() {
  cat <<EOF
Usage: ./BuildTool.sh [options]

Options:
  --setup-only      Check/install build environment (best-effort) and exit
  --no-commit       Build successfully but do not auto-commit
  --apk-only        Build debug APK only (default)
  --with-aab        Also build release AAB (only use when you explicitly want it)
  --help            Show this help

Behavior:
  - Disables Gradle daemon
  - Increments versionCode and versionName on every build
  - Copies artifacts to $DIST_DIR/ with app name + versionCode
  - Commits successful build changes using $COMMIT_MSG_FILE (clears after commit; fallback: "No Details")
EOF
}

SETUP_ONLY=false
DO_COMMIT=true
WITH_AAB=false

for arg in "$@"; do
  case "$arg" in
    --setup-only) SETUP_ONLY=true ;;
    --no-commit) DO_COMMIT=false ;;
    --apk-only) WITH_AAB=false ;;
    --with-aab) WITH_AAB=true ;;
    --help|-h) usage; exit 0 ;;
    *) echo "Unknown option: $arg" >&2; usage; exit 1 ;;
  esac
done

need_cmd() {
  command -v "$1" >/dev/null 2>&1 || {
    echo "Missing required command: $1" >&2
    exit 1
  }
}

ensure_java() {
  need_cmd java
  local major
  major="$(java -version 2>&1 | awk -F[\".] '/version/ {print $2}')"
  if [[ "${major:-0}" -lt 17 ]]; then
    echo "Java 17+ is required. Found Java ${major:-unknown}." >&2
    exit 1
  fi
}

ensure_android_sdk() {
  if [[ -z "${ANDROID_HOME:-}" ]]; then
    export ANDROID_HOME="$ROOT_DIR/.android-sdk"
  fi
  export ANDROID_SDK_ROOT="$ANDROID_HOME"
  export PATH="$ANDROID_HOME/cmdline-tools/latest/bin:$ANDROID_HOME/platform-tools:$PATH"

  if [[ ! -x "$ANDROID_HOME/cmdline-tools/latest/bin/sdkmanager" ]]; then
    need_cmd curl
    need_cmd unzip

    mkdir -p "$ANDROID_HOME/cmdline-tools"
    local zip_path="$ANDROID_HOME/cmdline-tools/commandlinetools.zip"

    echo "Downloading Android command line tools..."
    curl -L -o "$zip_path" \
      "https://dl.google.com/android/repository/commandlinetools-linux-11076708_latest.zip"

    rm -rf "$ANDROID_HOME/cmdline-tools/latest" "$ANDROID_HOME/cmdline-tools/cmdline-tools"
    unzip -q "$zip_path" -d "$ANDROID_HOME/cmdline-tools"
    mv "$ANDROID_HOME/cmdline-tools/cmdline-tools" "$ANDROID_HOME/cmdline-tools/latest"
    rm "$zip_path"
  fi

  yes | sdkmanager --licenses >/dev/null || true

  sdkmanager \
    "platform-tools" \
    "platforms;android-$API_LEVEL" \
    "build-tools;$BUILD_TOOLS_VERSION" >/dev/null
}

ensure_gradle_wrapper() {
  if [[ ! -x "./gradlew" ]]; then
    if [[ -f "./gradlew" ]]; then
      chmod +x ./gradlew
    else
      echo "Missing Gradle wrapper ./gradlew. Please add/commit it first." >&2
      exit 1
    fi
  fi
}

gradle_no_daemon() {
  ./gradlew --no-daemon -Dorg.gradle.daemon=false "$@"
}

ensure_gitignore_entries() {
  touch .gitignore
  for entry in \
    "$COMMIT_MSG_FILE" \
    ".android-sdk/" \
    ".gradle/" \
    "$DIST_DIR/" \
    "local.properties" \
    "**/build/" \
    "*.iml" \
    ".idea/" \
  ; do
    grep -qxF "$entry" .gitignore || echo "$entry" >> .gitignore
  done
}

increment_versions() {
  local gradle_file="$MODULE/build.gradle.kts"
  if [[ ! -f "$gradle_file" ]]; then
    echo "Cannot find $gradle_file" >&2
    exit 1
  fi

  python3 - "$gradle_file" <<'PY'
import re
import sys
from pathlib import Path

path = Path(sys.argv[1])
text = path.read_text()

m_code = re.search(r'\bversionCode\s*=\s*(\d+)', text)
m_name = re.search(r'\bversionName\s*=\s*"(\d+(?:\.\d+)*)"', text)

if not m_code:
    raise SystemExit('versionCode = <number> not found')
if not m_name:
    raise SystemExit('versionName = "<number>" not found (must be numeric, e.g. "1" or "1.0")')

old_code = int(m_code.group(1))
new_code = old_code + 1

old_name = m_name.group(1)
parts = old_name.split('.')
parts[-1] = str(int(parts[-1]) + 1)
new_name = '.'.join(parts)

text = re.sub(r'(\bversionCode\s*=\s*)\d+', r'\g<1>%d' % new_code, text, count=1)
text = re.sub(r'(\bversionName\s*=\s*)"\d+(?:\.\d+)*"', r'\g<1>"%s"' % new_name, text, count=1)

path.write_text(text)
print(new_code)
PY
}

build_artifacts() {
  gradle_no_daemon clean testDebugUnitTest assembleDebug
  if [[ "$WITH_AAB" == true ]]; then
    gradle_no_daemon bundleRelease
  fi
}

copy_artifacts() {
  local version_code="$1"
  mkdir -p "$DIST_DIR"

  local debug_apk
  debug_apk="$(find "$MODULE/build/outputs/apk/debug" -name "*.apk" | head -n 1 || true)"
  if [[ -z "$debug_apk" || ! -f "$debug_apk" ]]; then
    echo "Debug APK not found." >&2
    exit 1
  fi
  cp "$debug_apk" "$DIST_DIR/${APP_NAME}-v${version_code}-debug.apk"
  echo "Created: $DIST_DIR/${APP_NAME}-v${version_code}-debug.apk"

  if [[ "$WITH_AAB" == true ]]; then
    local release_aab
    release_aab="$(find "$MODULE/build/outputs/bundle/release" -name "*.aab" | head -n 1 || true)"
    if [[ -z "$release_aab" || ! -f "$release_aab" ]]; then
      echo "Release AAB not found." >&2
      exit 1
    fi
    cp "$release_aab" "$DIST_DIR/${APP_NAME}-v${version_code}-release.aab"
    echo "Created: $DIST_DIR/${APP_NAME}-v${version_code}-release.aab"
  fi
}

commit_successful_build() {
  git rev-parse --is-inside-work-tree >/dev/null 2>&1 || {
    echo "Not a git repo; skipping commit." >&2
    return
  }

  local message
  if [[ -s "$COMMIT_MSG_FILE" ]]; then
    message="$(cat "$COMMIT_MSG_FILE")"
  else
    message="No Details"
  fi

  git add -A
  if git diff --cached --quiet; then
    echo "No changes to commit."
  else
    git commit -m "$message"
  fi

  : > "$COMMIT_MSG_FILE"
}

main() {
  need_cmd python3
  ensure_java
  ensure_android_sdk
  ensure_gradle_wrapper
  ensure_gitignore_entries

  if [[ "$SETUP_ONLY" == true ]]; then
    echo "Build environment setup complete."
    exit 0
  fi

  local version_code
  version_code="$(increment_versions)"

  build_artifacts
  copy_artifacts "$version_code"

  if [[ "$DO_COMMIT" == true ]]; then
    commit_successful_build
  fi

  echo "Build completed successfully for versionCode $version_code."
}

main "$@"