#!/usr/bin/env bash
#
# Runs the desktop app (the same shared UI Android renders) on a virtual X display, so an agent in a
# headless container can launch it, look at it and click through it. See README.md next to this file.
#
#   tools/desktop-run/run-headless.sh start [options]   # build + launch, wait for the first paint
#   tools/desktop-run/run-headless.sh shot [file.png]   # screenshot (default: $RUN_DIR/shot.png)
#   tools/desktop-run/run-headless.sh logs              # tail of the app log, errors first
#   tools/desktop-run/run-headless.sh stop              # stop the app (Xvfb keeps running)
#
# start options (the login is transient: no key prompt, nothing saved; one of the three at most):
#   --fresh             start from an empty profile
#   --login <npub>      open logged in with a public key (npub, nprofile, name@domain)
#   --login-file <path> open logged in with the key in that file (an nsec stays out of `ps`), e.g.
#                       $RUN_DIR/profile/signup.nsec, read before --fresh clears the profile
#   --signup "<name>"   sign up a new account as the Sign Up button does; it publishes to public
#                       relays, and its nsec goes to $RUN_DIR/profile/signup.nsec
#   --local-only        the app reaches 127.0.0.1 and nothing else (its proxy points at a closed
#                       port), so a test account on AMETHYST_LOCAL_RELAYS can't publish elsewhere
#
# Env: AMETHYST_DISPLAY (default :99), AMETHYST_SCREEN (default 1600x1000x24),
#      AMETHYST_RUN_DIR (default /tmp/amethyst-desktop-run: log, profile, screenshots),
#      AMETHYST_START_TIMEOUT seconds (default 900: a cold Gradle build is slow),
#      AMETHYST_RUN_ARGS extra Gradle arguments, e.g. "-Damethyst.update.devCheck=true",
#      AMETHYST_LOGIN / AMETHYST_SIGNUP, which the app reads itself: what --login and --signup set.

set -uo pipefail

REPO_ROOT="$(cd "$(dirname "$0")/../.." && pwd)"
DRIVE="$REPO_ROOT/tools/desktop-run/Drive.java"
DISPLAY_NUM="${AMETHYST_DISPLAY:-:99}"
SCREEN="${AMETHYST_SCREEN:-1600x1000x24}"
RUN_DIR="${AMETHYST_RUN_DIR:-/tmp/amethyst-desktop-run}"
TIMEOUT="${AMETHYST_START_TIMEOUT:-900}"
LOG="$RUN_DIR/app.log"
DATA_DIR="$RUN_DIR/profile"
PID_FILE="$RUN_DIR/gradle.pid"

mkdir -p "$RUN_DIR"
export DISPLAY="$DISPLAY_NUM"
# Xvfb has no GL: start on the software renderer instead of failing over from OpenGL.
export SKIKO_RENDER_API="${SKIKO_RENDER_API:-SOFTWARE}"
# Anchored on the java binary so pgrep/pkill never match a shell whose command line mentions the class.
APP_PATTERN='^[^ ]*java .*AmethystDesktopKt'

drive() { java "$DRIVE" "$@" 2>&1 | grep -v '^Picked up JAVA_TOOL_OPTIONS'; }

app_running() { pgrep -f "$APP_PATTERN" > /dev/null; }

ensure_xvfb() {
  if xdpy_alive; then return; fi
  command -v Xvfb > /dev/null || { echo "Xvfb is not installed (apt-get install xvfb)" >&2; exit 1; }
  Xvfb "$DISPLAY_NUM" -screen 0 "$SCREEN" -nolisten tcp > "$RUN_DIR/xvfb.log" 2>&1 &
  for _ in $(seq 1 50); do xdpy_alive && return; sleep 0.1; done
  echo "Xvfb did not start on $DISPLAY_NUM; see $RUN_DIR/xvfb.log" >&2
  exit 1
}

# The X socket exists once Xvfb accepts connections.
xdpy_alive() { [ -S "/tmp/.X11-unix/X${DISPLAY_NUM#:}" ] && pgrep -f "^[^ ]*Xvfb $DISPLAY_NUM" > /dev/null; }

stop_app() {
  pkill -f "$APP_PATTERN" 2> /dev/null
  [ -f "$PID_FILE" ] && kill "$(cat "$PID_FILE")" 2> /dev/null
  rm -f "$PID_FILE"
  for _ in $(seq 1 50); do app_running || return 0; sleep 0.2; done
  pkill -9 -f "$APP_PATTERN" 2> /dev/null
}

print_errors() {
  # Uncaught exceptions, crash reports and Compose errors, most useful first.
  grep -nE 'Exception|Error:|FATAL|\bE/|Caused by' "$LOG" | grep -vE 'JAVA_TOOL_OPTIONS' | head -40
}

case "${1:-}" in
  start)
    shift
    fresh=false
    local_only=false
    account_options=0
    while [ $# -gt 0 ]; do
      case "$1" in
        --fresh) fresh=true ;;
        --local-only) local_only=true ;;
        --login)
          [ $# -ge 2 ] || { echo "--login needs a key" >&2; exit 2; }
          # On the command line the key shows in `ps` and in the shell history: public keys only.
          # Any case, as the app reads keys; a bare 64-char hex key or a seed phrase is a private key.
          login_lower="$(printf '%s' "$2" | tr '[:upper:]' '[:lower:]')"
          if [[ "$login_lower" == nsec1* || "$login_lower" == ncryptsec1* || "$login_lower" =~ ^[0-9a-f]{64}$ || "$2" =~ [[:space:]] ]]; then
            echo "--login takes public keys only: a private key on the command line shows in ps. Use --login-file." >&2
            exit 2
          fi
          export AMETHYST_LOGIN="$2"
          unset AMETHYST_SIGNUP
          account_options=$((account_options + 1))
          shift
          ;;
        --login-file)
          [ $# -ge 2 ] || { echo "--login-file needs a path" >&2; exit 2; }
          [ -r "$2" ] || { echo "Cannot read the key file $2" >&2; exit 2; }
          AMETHYST_LOGIN="$(tr -d '[:space:]' < "$2")"
          [ -n "$AMETHYST_LOGIN" ] || { echo "The key file $2 is empty" >&2; exit 2; }
          export AMETHYST_LOGIN
          unset AMETHYST_SIGNUP
          account_options=$((account_options + 1))
          shift
          ;;
        --signup)
          [ $# -ge 2 ] && [ -n "$2" ] || { echo "--signup needs a display name" >&2; exit 2; }
          export AMETHYST_SIGNUP="$2"
          unset AMETHYST_LOGIN
          account_options=$((account_options + 1))
          shift
          ;;
        *)
          echo "Unknown start option: $1" >&2
          sed -n '3,22p' "$0" >&2
          exit 2
          ;;
      esac
      shift
    done
    [ "$account_options" -le 1 ] || { echo "Pass only one of --login, --login-file and --signup" >&2; exit 2; }
    # After the options: --login-file may name the signup.nsec this deletes.
    $fresh && rm -rf "$DATA_DIR"
    # The window sizes itself to the screen only when no bounds were saved; keep it reproducible.
    rm -f "$DATA_DIR/window-bounds.properties"
    stop_app
    ensure_xvfb
    : > "$LOG"
    # Redirected as a whole, so no process keeps the caller's stdout open: `start | tail` returns.
    run_args="${AMETHYST_RUN_ARGS:-}"
    if $local_only; then
      # Every outbound connection here goes through the JVM's proxy, except http.nonProxyHosts.
      # Pointing the proxy at a closed port and narrowing that list to loopback (the sandbox's
      # list also lets LAN ranges through) leaves only this machine reachable.
      # The app inherits the environment from Gradle; --offline keeps Gradle off the network too.
      export JAVA_TOOL_OPTIONS="$(printf '%s' "${JAVA_TOOL_OPTIONS:-}" | sed -E 's/-Dhttps?\.(proxyHost|proxyPort|nonProxyHosts)=[^ ]*//g') -Dhttps.proxyHost=127.0.0.1 -Dhttps.proxyPort=9 -Dhttp.proxyHost=127.0.0.1 -Dhttp.proxyPort=9 -Dhttp.nonProxyHosts=localhost|127.*|[::1]"
      run_args="$run_args --offline"
    fi
    (cd "$REPO_ROOT" && exec nohup ./gradlew :desktopApp:run --console=plain \
      "-Damethyst.dataDir=$DATA_DIR" -Damethyst.debug=true $run_args) >> "$LOG" 2>&1 < /dev/null &
    echo $! > "$PID_FILE"
    echo "Building and launching (log: $LOG, profile: $DATA_DIR, DISPLAY=$DISPLAY_NUM)..."
    deadline=$((SECONDS + TIMEOUT))
    until app_running; do
      if ! kill -0 "$(cat "$PID_FILE")" 2> /dev/null; then
        echo "Gradle exited before the app started:" >&2
        tail -40 "$LOG" >&2
        exit 1
      fi
      [ $SECONDS -ge $deadline ] && { echo "Timed out waiting for the app JVM" >&2; tail -20 "$LOG" >&2; exit 1; }
      sleep 2
    done
    if ! drive waitpaint 120000; then
      echo "The app JVM started but never painted a window:" >&2
      print_errors >&2
      exit 1
    fi
    sleep 3 # first frames settle (fonts, theme)
    if ! app_running; then
      echo "The app painted and then died:" >&2
      print_errors >&2
      exit 1
    fi
    drive shot "$RUN_DIR/shot.png"
    echo "Running. Look at $RUN_DIR/shot.png; drive it with: DISPLAY=$DISPLAY_NUM java $DRIVE <cmd>"
    ;;
  shot)
    drive shot "${2:-$RUN_DIR/shot.png}"
    ;;
  logs)
    app_running && echo "app: running" || echo "app: NOT running"
    echo "--- errors ---"
    print_errors
    echo "--- tail ---"
    tail -30 "$LOG"
    ;;
  stop)
    stop_app
    echo "stopped"
    ;;
  *)
    sed -n '3,22p' "$0"
    exit 2
    ;;
esac