#!/bin/env bash

# Here's the score, kids.  There are a few different places from which we can
# get packages.  In priority order, they are:
#
# The CGTS packages we've built ourselves
# The CGTS packages that Jenkins has built (coming soon to a script near you)
# The CentOS packages in various repos
#    - Base OS
#    - OpenStack Repos
# EPEL (Extra Packages for Enterprise Linux)
#
# This script can function in two ways:
#   If you specify a filename, it assumes the file is a list of packages you
#      want to install, or dependencies you want to meet.  It installs whatever
#      is in the list into current directory.  Failure to find a dependency
#      results in a return code of 1
#
#   If no file is specified, we generate a file ($DEPLISTFILE) of dependencies
#      based on current directory
#
# We then continuously loop through generating new dependencies and installing
#  them until either all dependencies are met, or we cannot install anymore
#
# We also log where dependencies were installed from into
#   export/dist/report_deps.txt
#

# This function generates a simple file of dependencies we're trying to resolve
function generate_dep_list {
    TMP_RPM_DB=$(mktemp -d $(pwd)/tmp_rpm_db_XXXXXX)
    mkdir -p $TMP_RPM_DB
    rpm --initdb --dbpath $TMP_RPM_DB
    rpm --dbpath $TMP_RPM_DB --test -Uvh --replacefiles '*.rpm' >> $DEPDETAILLISTFILE 2>&1
    rpm --dbpath $TMP_RPM_DB --test -Uvh --replacefiles '*.rpm' 2>&1 \
        | grep -v "error:" \
        | grep -v "warning:" \
        | grep -v "Preparing..." \
        | sed "s/ is needed by.*$//" | sed "s/ >=.*$//" | sort -u > $DEPLISTFILE
    \rm -rf $TMP_RPM_DB
}

# Takes a list of requirements (either explcit package name, or capabilities
# to provide) and install packages to meet those dependancies
#
# We take the list of requirements and first try to look them up based on
# package name.  If we can't find a package with the name of the requirement,
# we use --whatprovides to complete the lookup.
#
# The reason for this initial name-based attempt is that a couple of funky
# packages (notably -devel packages) have "Provides:" capabilities which
# conflict with named packages.  So if explictly say we want "xyz" then we'll
# install the "xyz" package, rather than "something-devel" which has "xyz"
# capabilities.
function install_deps {
    local DEP_LIST=""
    local DEP_LIST_FILE="$1"

    # Temporary files are used in a few different ways
    # Here we essenitally create variable aliases to make it easier to read
    # the script
    local UNSORTED_PACKAGES=$TMPFILE
    local SORTED_PACKAGES=$TMPFILE1
    local UNRESOLVED_PACKAGES=$TMPFILE2

    rm -f $UNSORTED_PACKAGES

    while read DEP
    do
        DEP_LIST="${DEP_LIST} ${DEP}"
    done < $DEP_LIST_FILE

    echo "Debug: List of deps to resolve: ${DEP_LIST}"

    if [ -z "${DEP_LIST}" ]; then
        return 0
    fi

    # go through each repo and convert deps to packages based on package name
    for REPOID in `grep  '^[[].*[]]$' $YUM | grep -v '[[]main[]]' | awk -F '[][]' '{print $2 }'`; do
        echo "TMPDIR=$TMP_DIR repoquery -c $YUM --repoid=$REPOID --arch=x86_64,noarch ${DEP_LIST} --qf='%{name}'"
        TMPDIR=$TMP_DIR repoquery -c $YUM --repoid=$REPOID --arch=x86_64,noarch --qf='%{name}' ${DEP_LIST} | sed "s/kernel-debug/kernel/g" >> $UNSORTED_PACKAGES
        \rm -rf $TMP_DIR/yum-$USER-*
    done
    sort $UNSORTED_PACKAGES -u > $SORTED_PACKAGES

    # figure out any dependancies which could not be resolved based on
    # package name.  We use --whatpovides to deal with this
    #
    # First, we build a new DEP_LIST based on what was NOT found in
    # search-by-name attempt
    sort $DEP_LIST_FILE -u > $TMPFILE
    comm -2 -3 $TMPFILE $SORTED_PACKAGES > $UNRESOLVED_PACKAGES

    # If there are any requirements not resolved, look up the packages with
    # --whatprovides
    if [ -s $UNRESOLVED_PACKAGES ]; then
        DEP_LIST=""
        \cp $SORTED_PACKAGES $UNSORTED_PACKAGES
        while read DEP
        do
            DEP_LIST="${DEP_LIST} ${DEP}"
        done < $UNRESOLVED_PACKAGES

        DEP_LIST=$(echo "$DEP_LIST" | sed 's/^ //g')
        if [ "$DEP_LIST" != "" ]; then

            for REPOID in `grep  '^[[].*[]]$' $YUM | grep -v '[[]main[]]' | awk -F '[][]' '{print $2 }'`; do
                echo "TMPDIR=$TMP_DIR repoquery -c $YUM --repoid=$REPOID --arch=x86_64,noarch --whatprovides ${DEP_LIST} --qf='%{name}'"
                TMPDIR=$TMP_DIR repoquery -c $YUM --repoid=$REPOID --arch=x86_64,noarch --qf='%{name}' --whatprovides ${DEP_LIST} | sed "s/kernel-debug/kernel/g" >> $UNSORTED_PACKAGES
                \rm -rf $TMP_DIR/yum-$USER-*
            done
        fi

        sort -u $UNSORTED_PACKAGES > $SORTED_PACKAGES
    fi

    # clean up
    \rm -f $UNSORTED_PACKAGES $UNRESOLVED_PACKAGES

    # We now have, in SORTED_PACKAGES, a list of all packages that we need to install
    # to meet our dependancies
    DEP_LIST=" "
    while read DEP
    do
        DEP_LIST="${DEP_LIST}${DEP} "
    done < $SORTED_PACKAGES
    rm $SORTED_PACKAGES

    # go through each repo and install packages
    local TARGETS=${DEP_LIST}
    echo "Debug: Resolved list of deps to install: ${TARGETS}"
    local UNRESOLVED
    for REPOID in `grep  '^[[].*[]]$' $YUM | grep -v '[[]main[]]' | awk -F '[][]' '{print $2 }'`; do
        UNRESOLVED="$TARGETS"

        if [[ ! -z "${TARGETS// }" ]]; then
            REPO_PATH=$(cat $YUM | sed -n "/^\[$REPOID\]\$/,\$p" | grep '^baseurl=' | head -n 1 | awk -F 'file://' '{print $2}' | sed 's:/$::')
            >&2  echo "TMPDIR=$TMP_DIR repoquery -c $YUM --repoid=$REPOID --arch=x86_64,noarch --resolve $TARGETS --qf='%{name} %{name}-%{version}-%{release}.%{arch}.rpm %{relativepath}'"
            TMPDIR=$TMP_DIR repoquery -c $YUM --repoid=$REPOID --arch=x86_64,noarch --resolve $TARGETS --qf="%{name} %{name}-%{version}-%{release}.%{arch}.rpm %{relativepath}" | sort -r -V > $TMPFILE
            \rm -rf $TMP_DIR/yum-$USER-*

            while read STR
            do
                >&2 echo "STR=$STR"
                if [ "x$STR" == "x" ]; then
                    continue
                fi

                PKG=`echo $STR | cut -d " " -f 1`
                PKG_FILE=`echo $STR | cut -d " " -f 2`
                PKG_REL_PATH=`echo $STR | cut -d " " -f 3`
                PKG_PATH="${REPO_PATH}/${PKG_REL_PATH}"

                >&2 echo "Installing PKG=$PKG PKG_FILE=$PKG_FILE PKG_REL_PATH=$PKG_REL_PATH PKG_PATH=$PKG_PATH from repo $REPOID"
                cp $PKG_PATH .
                if [ $? -ne 0 ]; then
                    >&2 echo "  Here's what I have to work with..."
                    >&2 echo "  TMPDIR=$TMP_DIR repoquery -c $YUM --repoid=$REPOID --arch=x86_64,noarch --resolve $PKG --qf=\"%{name} %{name}-%{version}-%{release}.%{arch}.rpm %{relativepath}\""
                    >&2 echo "  PKG=$PKG PKG_FILE=$PKG_FILE REPO_PATH=$REPO_PATH PKG_REL_PATH=$PKG_REL_PATH PKG_PATH=$PKG_PATH"
                fi

                echo $UNRESOLVED | grep $PKG >> /dev/null
                if [ $? -eq 0 ]; then
                    echo "$PKG found in $REPOID as $PKG" >> $BUILT_REPORT
                    echo "$PKG_PATH" >> $BUILT_REPORT
                    UNRESOLVED=$(echo "$UNRESOLVED" | sed "s# $PKG # #g")
                else
                    echo "$PKG satisfies unknown target in $REPOID" >> $BUILT_REPORT
                    echo "  but it doesn't match targets, $UNRESOLVED" >> $BUILT_REPORT
                    echo "  path $PKG_PATH" >> $BUILT_REPORT
                    FOUND_UNKNOWN=1
                fi
            done < $TMPFILE #<<< "$(TMPDIR=$TMP_DIR repoquery -c $YUM --repoid=$REPOID --arch=x86_64,noarch --resolve $TARGETS --qf=\"%{name} %{name}-%{version}-%{release}.%{arch}.rpm %{relativepath}\" | sort -r -V)"
                        \rm -rf $TMP_DIR/yum-$USER-*
            TARGETS="$UNRESOLVED"
        fi
    done
    >&2 echo "Debug: Packages still unresolved: $UNRESOLVED"
    echo "Debug: Packages still unresolved: $UNRESOLVED" >> $WARNINGS_REPORT
    echo "Debug: Packages still unresolved: $UNRESOLVED" >> $BUILT_REPORT
    >&2 echo ""
}

function check_all_explicit_deps_installed {

    PKGS_TO_CHECK=" "
    while read PKG_TO_ADD
    do
        PKGS_TO_CHECK="$PKGS_TO_CHECK ${PKG_TO_ADD}"
    done < $DEPLISTFILE
    rpm -qp $MY_WORKSPACE/export/dist/isolinux/Packages/*.rpm --qf="%{name}\n" --nosignature > $TMPFILE

    while read INSTALLED_PACKAGE
    do
        echo $PKGS_TO_CHECK | grep -q "${INSTALLED_PACKAGE}"
        if [ $? -eq 0 ]; then
            PKGS_TO_CHECK=`echo $PKGS_TO_CHECK | sed "s/^${INSTALLED_PACKAGE} //"`
            PKGS_TO_CHECK=`echo $PKGS_TO_CHECK | sed "s/ ${INSTALLED_PACKAGE} / /"`
            PKGS_TO_CHECK=`echo $PKGS_TO_CHECK | sed "s/ ${INSTALLED_PACKAGE}\$//"`
            PKGS_TO_CHECK=`echo $PKGS_TO_CHECK | sed "s/^${INSTALLED_PACKAGE}\$//"`
        fi
    done < $TMPFILE

    if [ -z "$PKGS_TO_CHECK" ]; then
        >&2 echo "All explicitly specified packages resolved!"
    else
        >&2 echo "Could not resolve packages: $PKGS_TO_CHECK"
        return 1
    fi
    return 0
}

ATTEMPTED=0
DISCOVERED=0
OUTPUT_DIR=$MY_WORKSPACE/export
TMP_DIR=$MY_WORKSPACE/tmp
YUM=$OUTPUT_DIR/yum.conf
DEPLISTFILE=$OUTPUT_DIR/deps.txt
DEPDETAILLISTFILE=$OUTPUT_DIR/deps_detail.txt

BUILT_REPORT=$OUTPUT_DIR/local.txt
WARNINGS_REPORT=$OUTPUT_DIR/warnings.txt
LAST_TEST=$OUTPUT_DIR/last_test.txt
TMPFILE=$OUTPUT_DIR/cgts_deps_tmp.txt
TMPFILE1=$OUTPUT_DIR/cgts_deps_tmp1.txt
TMPFILE2=$OUTPUT_DIR/cgts_deps_tmp2.txt

touch "$BUILT_REPORT"
touch "$WARNINGS_REPORT"

for i in "$@"
do
case $i in
    -d=*|--deps=*)
    DEPS="${i#*=}"
    shift # past argument=value
    ;;
esac
done

mkdir -p $TMP_DIR

rm -f "$DEPDETAILLISTFILE"
# FIRST PASS we are being given a list of REQUIRED dependencies
if [ "${DEPS}x" != "x" ]; then
    cat $DEPS | grep -v "^#" | sed '/^\s*$/d' > $DEPLISTFILE
    install_deps $DEPLISTFILE
    if [ $? -ne 0 ]; then
        exit 1
    fi
fi

# check that we resolved them all
check_all_explicit_deps_installed
if [ $? -ne 0 ]; then
    >&2 echo "Error -- could not install all explicitly listed packages"
    exit 1
fi

ALL_RESOLVED=0

while [ $ALL_RESOLVED -eq 0 ]; do
    cp $DEPLISTFILE $DEPLISTFILE.old
    generate_dep_list
    if [ ! -s $DEPLISTFILE ]; then
        # no more dependencies!
        ALL_RESOLVED=1
    else
        DIFFLINES=`diff $DEPLISTFILE.old $DEPLISTFILE | wc -l`
        if [ $DIFFLINES -eq 0 ]; then
            >&2 echo "Warning: Infinite loop detected in dependency resolution.  See $DEPLISTFILE for details -- exiting"
            >&2 echo "These RPMS had problems (likely version conflicts)"
            >&2 cat  $DEPLISTFILE

            echo "Warning: Infinite loop detected in dependency resolution See $DEPLISTFILE for details -- exiting" >> $WARNINGS_REPORT
            echo "These RPMS had problems (likely version conflicts)" >> $WARNINGS_REPORT
            cat  $DEPLISTFILE >> $WARNINGS_REPORT

            date > $LAST_TEST

            rm -f $DEPLISTFILE.old
            exit 1 # nothing fixed
        fi
        install_deps $DEPLISTFILE
        if [ $? -ne 0 ]; then
            exit 1
        fi
    fi
done

exit 0