#! /usr/bin/env bash

# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# This script will generate/regenerate the thrift stubs for Airavata Components: Credential Store, Orchestrator, GFac.

show_usage() {
	echo -e "Usage: $0 [Component to generate stubs]"
	echo ""
	echo "options:"
	echo -e "\tcs Generate/Update Credential Store Stubs"
	echo -e "\torch Generate/Update Orchestrator Stubs"
	echo -e "\tgfac Generate/Update GFac Stubs"
	echo -e "\tdm Generate/Update Data Manager Stubs"
	echo -e "\tall Generate/Update all stubs (Credential Store, Orchestrator, GFac)."
	echo -e "\t-h[elp] Print the usage options of this script"
}

if [ $# -lt 1 ]
then
	show_usage
	exit 1
fi

if [[ $1 == "-h" ||$1 == "--help" ]]
then
	show_usage
	exit 0
fi

# Generation of thrift files will require installing Apache Thrift. Please add thrift to your path.
#  Verify is thrift is installed, is in the path is at a specified version.

REQUIRED_THRIFT_VERSION='0.9.3'
if hash thrift &> /dev/null; then
  THRIFT_EXEC=$(which thrift)
else
  THRIFT_EXEC=/usr/local/bin/thrift
fi

VERSION=$($THRIFT_EXEC -version 2>/dev/null | grep -F "${REQUIRED_THRIFT_VERSION}" |  wc -l)
if [ "$VERSION" -ne 1 ] ; then
    echo -e "ERROR:\t Apache Thrift version ${REQUIRED_THRIFT_VERSION} is required."
    echo -e "It is either not installed or is not in the path"
    exit 1
fi

# Global Constants used across the script
BASE_TARGET_DIR='target'

CS_THRIFT_FILE='credential-store-cpi.thrift'
CS_SRC_DIR='../../modules/credential-store/credential-store-stubs/src/main/java'

DM_THRIFT_FILE='data-manager-cpi.thrift'
DM_SRC_DIR='../../modules/data-manager/data-manager-stubs/src/main/java'

ORCHESTRATOR_THRIFT_FILE='orchestrator-cpi.thrift'
ORCHESTRATOR_SRC_DIR='../../modules/orchestrator/orchestrator-client/src/main/java'

GFAC_THRIFT_FILE='gfac-cpi.thrift'
GFAC_SRC_DIR='../../modules/gfac/gfac-client/src/main/java/'

# Initialize the thrift arguments.
#  Since most of the Airavata API and Data Models have includes, use recursive option by default.
#  Generate all the files in target directory
THRIFT_ARGS="-r -o ${BASE_TARGET_DIR}"
# Ensure the required target directories exists, if not create.
mkdir -p ${BASE_TARGET_DIR}

# The Funcation fail prints error messages on failure and quits the script.
fail() {
    echo $@
    exit 1
}

# The funcation add_license_header adds the ASF V2 license header to all java files within the specified generated
#   directory. The funcation also adds suppress all warnings annotation to all public classes and enum's
#  To Call:
#   add_license_header $generated_code_directory
add_license_header() {

    # Fetch the generated code directory passed as the argument
    GENERATED_CODE_DIR=$1

    # For each java file within the generated directory, add the ASF V2 LICENSE header
    for f in $(find ${GENERATED_CODE_DIR} -name '*.java'); do
      cat - ${f} >${f}-with-license <<EOF
    /*
     * Licensed to the Apache Software Foundation (ASF) under one or more
     * contributor license agreements.  See the NOTICE file distributed with
     * this work for additional information regarding copyright ownership.
     * The ASF licenses this file to You under the Apache License, Version 2.0
     * (the "License"); you may not use this file except in compliance with
     * the License.  You may obtain a copy of the License at
     *
     *     http://www.apache.org/licenses/LICENSE-2.0
     *
     * Unless required by applicable law or agreed to in writing, software
     * distributed under the License is distributed on an "AS IS" BASIS,
     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     * See the License for the specific language governing permissions and
     * limitations under the License.
     */
EOF
    mv ${f}-with-license ${f}
    done
}

# The function compares every generated java file with the one in specified existing source location. If the comparison
#   shows a difference, then it replaces with the newly generated file (with added license header).
#  To Call:
#   copy_changed_files $generated_code_directory $existing_source_directory
copy_changed_files() {

    # Read all the function arguments
    GENERATED_CODE_DIR=$1
    WORKSPACE_SRC_DIR=$2

    echo "Generated sources are in ${GENERATED_CODE_DIR}"
    echo "Destination workspace is in ${WORKSPACE_SRC_DIR}"

    # Check if the newly generated files exist in the targetted workspace, if not copy. Only changed files will be synced.
    #  the extra slash to GENERATED_CODE_DIR is needed to ensure the parent directory itself is not copied.
    rsync -auv ${GENERATED_CODE_DIR}/ ${WORKSPACE_SRC_DIR}
}

# The function generates the thrify stubs and copies to the specified directory.
#  To Call:
#   generate_thrift_stubs $component_thrift_file $component_src_dir
generate_thrift_stubs() {

    COMPONENT_THRIFT_FILE=$1
    COMPONENT_SRC_DIR=$2

    #Java generation directory
    JAVA_GEN_DIR=${BASE_TARGET_DIR}/gen-java

    # As a precaution remove and previously generated files if exists
    rm -rf ${JAVA_GEN_DIR}

    # Using thrify Java generator, generate the java classes based on components CPI.
    $THRIFT_EXEC ${THRIFT_ARGS} --gen java ${COMPONENT_THRIFT_FILE} || fail unable to generate java thrift classes

    # Remove generated model classes, airavata api thrift file will generate those.
    echo "Remove generated model classes ${JAVA_GEN_DIR}/org/airavata/apache/model"
    rm -rf ${JAVA_GEN_DIR}/org/apache/airavata/model

    # For the generated java classes add the ASF V2 License header
    add_license_header $JAVA_GEN_DIR

    # Compare the newly generated classes with existing java generated skelton/stub sources and replace the changed ones.
    copy_changed_files ${JAVA_GEN_DIR} ${COMPONENT_SRC_DIR}

    echo "Successfully generated new sources, compared against exiting code and replaced the changed files"

}

for arg in "$@"
do
    case "$arg" in
    all)    echo "Generate all (credential store, orchestrator, gfac) Stubs"
            generate_thrift_stubs ${CS_THRIFT_FILE} ${CS_SRC_DIR}
            generate_thrift_stubs ${ORCHESTRATOR_THRIFT_FILE} ${ORCHESTRATOR_SRC_DIR}
            generate_thrift_stubs ${GFAC_THRIFT_FILE} ${GFAC_SRC_DIR}
            generate_thrift_stubs ${DM_THRIFT_FILE} ${DM_SRC_DIR}
            ;;
    cs)   echo "Generating Credential Store Stubs"
            generate_thrift_stubs ${CS_THRIFT_FILE} ${CS_SRC_DIR}
            ;;
    orch)    echo "Generate Orchestrator Stubs"
            generate_thrift_stubs ${ORCHESTRATOR_THRIFT_FILE} ${ORCHESTRATOR_SRC_DIR}
            ;;
    gfac)    echo "Generate GFac Stubs"
            generate_thrift_stubs ${GFAC_THRIFT_FILE} ${GFAC_SRC_DIR}
            ;;
    dm)    echo "Generate Data Manager Stubs"
            generate_thrift_stubs ${DM_THRIFT_FILE} ${DM_SRC_DIR}
            ;;
    *)      echo "Invalid or unsupported option"
    	    show_usage
	        exit 1
            ;;
    esac
done

####################
# Cleanup and Exit #
####################
# CleanUp: Delete the base target build directory
#rm -rf ${BASE_TARGET_DIR}

exit 0