#!/bin/bash
###########################################################################

function get_files {
# determine the changed files and extract them from the repo to the build structure.
    git diff-tree -r ${ORIGIN}..${BRANCH} |
        while IFS= read -r line
        do
        COMMIT_ID=$(echo $line | cut -f4 -d" " )
        SOURCE=$(echo $line | cut -f6 -d" " )
            echo "Identified: " ${SOURCE} " Commit: " ${COMMIT_ID}
        TARGET=$(basename ${SOURCE})
        echo "Target : " ${TARGET}
        echo ${TARGET} >> ${BUILD_PATH}/etc/build.txt

        echo "Extracting source from repo: " $SOURCE
        git show ${COMMIT_ID} > ${BUILD_PATH}/${SOURCE}
        echo "Building targets:"
    done
}

function build_targets {
    FILES=$(cat ${BUILD_PATH}/etc/build.txt)
    for i in $FILES
    do
        echo "Compiling: " $i
    done
}

function prep_build_tree {
#Check if build structure exists
        if [[ -d ${BUILD_PATH} ]]
        then
# clean source from the local build structre by removing and rebuilding it
            echo "Cleaning old build structure"
            find ${BUILD_PATH} -type f -exec rm -v {} ;
        else
# Create build structure
            echo "Creating build structure"
            mkdir -p ${BUILD_PATH}/APP/SOURCE
            mkdir -p ${BUILD_PATH}/APP/COPY
            mkdir -p ${BUILD_PATH}/etc
            mkdir -p ${BUILD_PATH}/LOADLIB
        fi
}

##############################################################################

read oldrev newrev refname
echo "Old revision: $oldrev"
echo "New revision: $newrev"
echo "Reference name: $refname"

BASE_DIR=/home/mfcobol/SDLC/BUILD/Dev-Build
BRANCH=$(basename $refname)

#determine build type:
#   dev branch performs build using the dev build structure checked against master
#       other branches perform local builds for that branch only checked against dev.
case $BRANCH in

    dev ) BUILD=dev
        echo "Dev build identified: Branch: "${BRANCH}
        ORIGIN=master
        BUILD_PATH=${BASE_DIR}/${BUILD}/${BRANCH}
        prep_build_tree
        get_files
        build_targets ;;


    * )   BUILD=user
        echo "User build identified: Branch: "${BRANCH}
        ORIGIN=dev
        BUILD_PATH=${BASE_DIR}/${BUILD}/${BRANCH}
        prep_build_tree
        get_files
        build_targets ;;
esac