#!/bin/bash
#
# This script will launch the JNLP remoting client that Jenkins master server
# will use for the auto-discovery of this slave.
#

# The directory that Jenkins will execute the builds and store cache files.
# The directory has to be writeable for the user that the container is running
# under.

export JENKINS_HOME=/home/jenkins

# Make sure the Java clients have valid $HOME directory set
export HOME=${JENKINS_HOME}

export JAVA_VERSION=${USE_JAVA_VERSION:=java-21}

function linux_available_memory_bytes() {
  local kbytes
  kbytes=$(cat /proc/meminfo | grep MemAvailable | awk '{print $2}')
  echo $((kbytes*(2**10)))
}

function container_max_memory_bytes() {
  local limit
  if [ -f /sys/fs/cgroup/memory/memory.limit_in_bytes ]; then
    # cgroups v1
    cat /sys/fs/cgroup/memory/memory.limit_in_bytes
    return
  fi
  if [ -f /sys/fs/cgroup/memory.max ]; then
    # cgroups v2
    limit=$(cat /sys/fs/cgroup/memory.max)
    if [ "${limit}" == 'max' ]; then
      linux_available_memory_bytes
      return
    fi
    echo $limit
    return
  fi
  linux_available_memory_bytes
}

CONTAINER_MEMORY_IN_BYTES=$(container_max_memory_bytes)
CONTAINER_MEMORY_IN_MB=$((CONTAINER_MEMORY_IN_BYTES/2**20))

if [[ "$(uname -m)" == "x86_64" ]]; then
	alternatives --set java $(alternatives --display java | grep $JAVA_VERSION | awk '/family.*x86_64/ { print $1; }')
	alternatives --set javac $(alternatives --display javac | grep $JAVA_VERSION | awk '/family.*x86_64/ { print $1; }')
#set JVM for all other archs
else
  alternatives --set java $(alternatives --display java | grep $JAVA_VERSION | awk '/family.*'$(uname -m)'/ { print $1; }')
  alternatives --set javac $(alternatives --display javac | grep $JAVA_VERSION | awk '/family.*'$(uname -m)'/ { print $1; }')
fi

echo "OPENSHIFT_JENKINS_JVM_ARCH='${OPENSHIFT_JENKINS_JVM_ARCH}', CONTAINER_MEMORY_IN_MB='${CONTAINER_MEMORY_IN_MB}', using $(readlink /etc/alternatives/java)"

shopt -s nocasematch
if [[ -z "${SKIP_NO_PROXY_DEFAULT}" || \
    "${SKIP_NO_PROXY_DEFAULT}" != "false" ]]; then
  # we do not want jenkins svc or jenkins-jnlp svc
  # communication going through a http proxy
  # env vars to consider:
  # - no_proxy and NO_PROXY; case of string varies tool to tool
  # - JENKINS_URL and JENKINS_TUNNEL comes from k8s plugin
  # based on how our master image configures the cloud, but we need to strip the host / port
  jenkins_http_host=`echo $JENKINS_URL | sed 's#https://##' | sed 's#http://##' | cut -f1 -d":"`
  jnlp_http_host=`echo $JENKINS_TUNNEL | sed 's#https://##' | sed 's#http://##' | cut -f1 -d":"`
  # check if set to avoid having a comma as the last char
  if [[ -z "${no_proxy}" ]]; then
     export no_proxy=$jenkins_http_host,$jnlp_http_host
  else
    export no_proxy=$jenkins_http_host,$jnlp_http_host,$no_proxy
  fi
  if [[ -z "${NO_PROXY}" ]]; then
     export NO_PROXY=$jenkins_http_host,$jnlp_http_host
  else
    export NO_PROXY=$jenkins_http_host,$jnlp_http_host,$NO_PROXY
  fi
fi
shopt -u nocasematch

# Configure the slave image
source /usr/local/bin/configure-slave
source /usr/local/bin/configure-agent

set -e

# As of version 1.6.0 of the Jenkins Kubernetes plugin,
# args are no longer passed to jnlp container if not present in containerTemplate
# See https://github.com/jenkinsci/kubernetes-plugin/pull/315
# In this case, we use JENKINS_SECRET and JENKINS_NAME for launcher arguments
# This is made worse if using Declarative pipeline and specifying yaml for the podTemplate
# In this case, ${computer.*} is not resolvable.

# If no args are given, we examine env vars and add to arg list.
if [[ $# -eq 0 ]]; then
  if [ ! -z "$JENKINS_SECRET" ]; then
    set -- "${@}" "$JENKINS_SECRET"
  fi
  if [ ! -z "$JENKINS_NAME" ]; then
    set -- "${@}" "$JENKINS_NAME"
  fi

  # If Kubernetes plugin is configured to use WebSocket, add the -webSocket flag to the arguments
  if [[ "$@" != *"-webSocket"* ]]; then
    if [ ! -z "$JENKINS_WEB_SOCKET" ]; then
      set -- "${@}" "-webSocket"
    fi
  fi

fi

# if `docker run` has 2 or more arguments the user is passing jenkins launcher arguments
if [[ $(echo "$@" | awk '{print NF}') -gt 1 ]]; then
  JAR="${JENKINS_HOME}/remoting.jar"
  PARAMS=""

  # if -url is not provided try env vars
  if [[ "$@" != *"-url "* ]]; then
    if [ ! -z "$JENKINS_URL" ]; then
      PARAMS="$PARAMS -url $JENKINS_URL"
    elif [ ! -z "$JENKINS_SERVICE_HOST" ] && [ ! -z "$JENKINS_SERVICE_PORT" ]; then
      PARAMS="$PARAMS -url http://$JENKINS_SERVICE_HOST:$JENKINS_SERVICE_PORT"
    fi
  fi

  # Avoid double slashes in URL
  # ${string%%substring} Deletes longest match of $substring from back of $string.
  echo "Downloading ${JENKINS_URL%%/}/jnlpJars/remoting.jar ..."
  curl -sS ${JENKINS_URL%%/}/jnlpJars/remoting.jar -o ${JAR}

  # if -tunnel is not provided try env vars
  if [[ "$@" != *"-tunnel "* ]]; then
    if [ ! -z "$JENKINS_TUNNEL" ]; then
      PARAMS="$PARAMS -tunnel $JENKINS_TUNNEL"
    elif [ ! -z "$JENKINS_SLAVE_SERVICE_HOST" ] && [ ! -z "$JENKINS_SLAVE_SERVICE_PORT" ]; then
      PARAMS="$PARAMS -tunnel $JENKINS_SLAVE_SERVICE_HOST:$JENKINS_SLAVE_SERVICE_PORT"
    fi
  fi

  if [[ -z "${JAVA_TOOL_OPTIONS}" ]]; then
    # these options will automatically be picked up by any JVM process but can
    # be overridden on that process' command line.
    #JAVA_TOOL_OPTIONS="-XX:+UnlockExperimentalVMOptions -XX:+UseCGroupMemoryLimitForHeap -Dsun.zip.disableMemoryMapping=true"
    export JAVA_TOOL_OPTIONS
  fi

  # assume k8s/docker memory limit was set if memory.limit_in_bytes < 1TiB
  if [[ "${CONTAINER_MEMORY_IN_BYTES}" -lt $((2**40)) ]]; then
    # set this JVM's -Xmx and -Xms if not set already (not propagated to any
    # child JVMs).  -Xmx can be calculated as a percentage, capped to a maximum,
    # or specified straight.  -Xms can be calculated as a percentage or
    # specified straight.  For the JNLP slave by default we specify -Xmx of 50%,
    # uncapped; -Xms unspecified (JVM default is 1/64 of -Xmx).

    if [[ -z "$CONTAINER_HEAP_PERCENT" ]]; then
        CONTAINER_HEAP_PERCENT=0.50
    fi

    CONTAINER_HEAP_MAX=$(echo "${CONTAINER_MEMORY_IN_MB} ${CONTAINER_HEAP_PERCENT}" | awk '{ printf "%d", $1 * $2 }')
    if [[ $JNLP_MAX_HEAP_UPPER_BOUND_MB && $CONTAINER_HEAP_MAX -gt $JNLP_MAX_HEAP_UPPER_BOUND_MB ]]; then
      CONTAINER_HEAP_MAX=$JNLP_MAX_HEAP_UPPER_BOUND_MB
    fi
    if [[ -z "$JAVA_MAX_HEAP_PARAM" ]]; then
      JAVA_MAX_HEAP_PARAM="-Xmx${CONTAINER_HEAP_MAX}m"
    fi

    if [[ "$CONTAINER_INITIAL_PERCENT" ]]; then
      CONTAINER_INITIAL_HEAP=$(echo "${CONTAINER_HEAP_MAX} ${CONTAINER_INITIAL_PERCENT}" | awk '{ printf "%d", $1 * $2 }')
      if [[ -z "$JAVA_INITIAL_HEAP_PARAM" ]]; then
        JAVA_INITIAL_HEAP_PARAM="-Xms${CONTAINER_INITIAL_HEAP}m"
      fi
    fi
  fi

  if [[ -z "$JAVA_GC_OPTS" ]]; then
    # See https://developers.redhat.com/blog/2014/07/22/dude-wheres-my-paas-memory-tuning-javas-footprint-in-openshift-part-2/ .
    # The values are aggressively set with the intention of relaxing GC CPU time
    # restrictions to enable it to free as much as possible, as well as
    # encouraging the GC to free unused heap memory back to the OS.
    JAVA_GC_OPTS="-XX:+UseParallelGC -XX:MinHeapFreeRatio=5 -XX:MaxHeapFreeRatio=10 -XX:GCTimeRatio=4 -XX:AdaptiveSizePolicyWeight=90"
  fi

  if [[ "${USE_JAVA_DIAGNOSTICS}" || "${JAVA_DIAGNOSTICS}" ]]; then
    echo "Warning: USE_JAVA_DIAGNOSTICS and JAVA_DIAGNOSTICS are legacy and may be removed in a future version of this script."
  fi

  if [[ "${USE_JAVA_DIAGNOSTICS}" ]]; then
    JAVA_DIAGNOSTICS="-XX:NativeMemoryTracking=summary -XX:+PrintGC -XX:+PrintGCDateStamps -XX:+PrintGCTimeStamps -XX:+UnlockDiagnosticVMOptions"
  fi

  if [[ "${CONTAINER_CORE_LIMIT}" ]]; then
    JAVA_CORE_LIMIT="-XX:ParallelGCThreads=${CONTAINER_CORE_LIMIT} -Djava.util.concurrent.ForkJoinPool.common.parallelism=${CONTAINER_CORE_LIMIT} -XX:CICompilerCount=2"
  fi

  if [[ -z "${JAVA_FIPS_OPTIONS}" ]]; then
    JAVA_FIPS_OPTIONS="-Dcom.redhat.fips=false"
  fi

  if [[ -z "${JNLP_JAVA_OPTIONS}" ]]; then
    JNLP_JAVA_OPTIONS="$JAVA_FIPS_OPTIONS $JAVA_GC_OPTS $JAVA_INITIAL_HEAP_PARAM $JAVA_MAX_HEAP_PARAM $JAVA_CORE_LIMIT $JAVA_DIAGNOSTICS"
  fi

  # Deal with embedded escaped spaces in JNLP_JAVA_OVERRIDES.
  # JNLP_JAVA_OVERRIDES='-Dfoo -Dbar' => append -Dfoo -Dbar to java invocation
  # JNLP_JAVA_OVERRIDES='-Dfoo\ bar' => append '-Dfoo bar' to java invocation
  read -a JNLP_JAVA_OVERRIDES_ARRAY <<< "$JNLP_JAVA_OVERRIDES"

  set -x
  cd ${JENKINS_DIR} && exec java -Duser.home=${HOME} $JNLP_JAVA_OPTIONS \
                                 "${JNLP_JAVA_OVERRIDES_ARRAY[@]}" \
                                 -cp $JAR hudson.remoting.jnlp.Main \
                                 -headless $PARAMS "$@"
fi

exec "$@"