#!/bin/bash

source ScriptFunctions
Import File
Import GoboLinux
Import Log
Import OptionParser

### Options ###################################################################

scriptDescription="Install RPM packages on GoboLinux."
scriptCredits="Copyright (C) Lucas C. Villa Real, 2016 - Released under the GNU GPL."
helpOnNoArguments=yes
scriptUsage="<file.rpm> [file.rpm]"
scriptExample="xispita-2.0.3-1.x86_64.rpm"

Add_Option_Entry   "n" "app-name"       "Override program name"
Add_Option_Entry   "e" "version-number" "Override program version number"
Add_Option_Entry   "l" "symlink"        "If symlinks should be created and wether they should be forced on conflicts."  "yes" "yes no force"
Add_Option_Boolean "W" "no-web"         "Do not search the web to resolve dependencies."
Parse_Options "$@"

### Functions #################################################################

function fetch_rpm() {
    local rpmfile="$1"
    local filename=$(basename "$rpmfile")
    if Is_URL "$rpmfile"
    then
        if wget --help | grep -q "no-check-certificate"
        then wget_cmd="wget --no-check-certificate"
        else wget_cmd="wget"
        fi
        Quiet ${wget_cmd} -c "${rpmfile}" -O "${goboTemp}/${filename}" || Die "Error downloading package."
        echo "${goboTemp}/${filename}"
    else
        echo "$rpmfile"
    fi
}

function uncompress_rpm() {
    local rpmfile="$1"
    local payload_compressor=$(rpminfo --compressor "$rpmfile")
    local cpiofile=$(basename "$rpmfile").cpio${payload_compressor:+.$payload_compressor}
    
    Log_Normal "Extracting RPM payload."
    rpm2cpio < "$rpmfile" > "$cpiofile"

    if [ "$payload_compressor" = "xz" ]
    then
        Log_Normal "Decompressing $payload_compressor payload."
        xz -d "$cpiofile"
        cpiofile=$(basename "$rpmfile").cpio
    fi

    Log_Normal "Extracting CPIO archive."
    cpio -d -i < "$cpiofile"
    rm -f -- "$cpiofile"
}

function determine_flattening_level() {
    local rootdirs="bin$\|sbin$\|lib$\|lib64$\|libexec$\|include$\|share$"
    local filenames=$(for i in "${rpmfiles[@]}"; do rpminfo --filenames $i; done)

    Log_Verbose "$filenames"
    if echo "$filenames" | grep -q "/opt/$rootdirs"
    then
        # 1-level /opt hierarchy
        echo "1"
    elif echo "$filenames" | grep -q "/opt/[^/]*/$rootdirs"
    then
        # 2-level /opt hierarchy
        echo "2"
    elif echo "$filenames" | grep -q "/opt"
    then
        # Get the longest common prefix among the $filenames list that starts
        # with "/opt" and then determine how many path levels we have there.
        local commonprefix=$(echo "$filenames" | grep "/opt" | sed -e 'N;s/^\(.*\).*\n\1.*$/\1\n\1/;D')
        local numslashes=$(echo "$commonprefix" | grep -o "/" | wc -l)
        let numslashes=numslashes-1
        if [ "$numslashes" = 1 ]
        then
            Log_Verbose "Package seems to have a 1-level /opt structure"
            echo "1"
        elif [ "$numslashes" = 2 ]
        then
            Log_Verbose "Package seems to have a 2-level /opt structure"
            echo "2"
        else
            Log_Error "Could not determine this package's /opt structure, assuming 2-level"
            echo "2"
        fi
    fi
}

function flatten_rpm() {
    local rpmfile="$1"

    Log_Normal "Flattening directory structure."

    function create_opt_links() {
        local vendordir="$1"
        local unmanagedopt="Resources/Unmanaged/opt"
        for pkgdir in $(basename --multiple ./opt/$vendordir/*)
        do
            mkdir ${verbose} -p "${unmanagedopt}/$vendordir/$pkgdir"
            if [ -h "/opt/$vendordir/$pkgdir" ]
            then
                Log_Error "Too many programs are attempting to populate /opt/$vendordir/$pkgdir"
                Log_Error "This feature is not supported by InstallPackage-RPM at this time."
                continue
            fi
            for optfile in $(basename --multiple ./opt/$vendordir/$pkgdir/*)
            do
                if [ ! -e "${unmanagedopt}/$vendordir/$pkgdir/$optfile" ]
                then
                    ln ${verbose} -fs $target/$optfile "${unmanagedopt}/$vendordir/$pkgdir/$optfile"
                fi
            done
        done
    }

    function flatten_opt_1_level() {
        # Flatten 1-level dir: opt/pkgname/{bin,sbin,...}
        cp ${verbose} -a ./opt/*/* .
        create_opt_links ""
        realpath ./opt/* | sed "s,$(realpath $PWD),,g" >> Resources/UnmanagedFiles
    }

    function flatten_opt_2_levels() {
        # Flatten 2-levels dir: opt/vendorname/pkgname/{bin,sbin,...}
        cp ${verbose} -a ./opt/*/*/* .
        for vendordir in $(basename --multiple ./opt/*)
        do
            create_opt_links "$vendordir"
        done
        realpath ./opt/*/* | sed "s,$(realpath $PWD),,g" >> Resources/UnmanagedFiles
    }

    if [ -d "./usr" ]
    then
        cp ${verbose} -a ./usr/* .
        rm -rf -- ./usr
    fi
    if [ -d "./etc" ]
    then
        mkdir -p Resources/Defaults/Settings
        mv ${verbose} ./etc/* Resources/Defaults/Settings
        rm -rf -- ./etc
    fi
    if [ -d "./lib64" ]
    then
        Quiet rmdir lib
        if [ ! -d "./lib" ]
        then mv ./lib64 lib
        else cp -a ./lib64/* ./lib/
        fi
        rm -rf ./lib64
    fi
    if [ -d "./var" ]
    then
        mkdir -p Resources/Unmanaged/$goboVariable
        find ./var | sed "s,./var,$goboVariable,g" >> Resources/UnmanagedFiles
        mv ${verbose} ./var/* Resources/Unmanaged/$goboVariable
        rm -rf -- ./var
    fi
    if [ -d "./opt" ]
    then
        # Prevent the creation of backlinks to directories that would be pruned later on
        find share -type d | xargs rmdir -p --ignore-fail-on-non-empty
        rmdir * 2> /dev/null
        mkdir -p Resources/Unmanaged/opt
        if [ "$flatteninglevel" = "1" ]
        then
            Log_Verbose "Flattening 1-level /opt directory"
            flatten_opt_1_level
        elif [ "$flatteninglevel" = "2" ]
        then
            Log_Verbose "Flattening 2-level /opt directory"
            flatten_opt_2_levels
        fi
        rm -rf -- ./opt
    fi
    if [ -e Resources/UnmanagedFiles ]
    then
        # If multiple RPM files are being merged, then ensure we have no dups
        cat Resources/UnmanagedFiles | sort -n | uniq > x && mv x Resources/UnmanagedFiles
    fi
    rmdir * 2> /dev/null
}

function is_inputfile() {
    local dependency="$1"
    local pkgname=$(echo "$dependency" | cut -d'(' -f1 | awk {'print $1'})
    printf "%s\n" "${rpmnames[@]}" | grep -q "^${pkgname}$" && return 0
    return 1
}

function populate_dependencies() {
    local rpmfile="$1"
    rpminfo --dependencies "$rpmfile" | while read dependency
    do
        if echo "$dependency" | grep -q "^/"
        then
            depinfo=$(take_dependency_from_path "$rpmfile" "$dependency" "")
            if [ "$depinfo" ]
            then echo "$depinfo"
            else echo "# Unresolved path-based dependency: $dependency"
            fi
        elif echo "$dependency" | grep -q "^lib.*\.so*\|.*\.so\.*"
        then
            libname=$(echo "$dependency" | cut -d'(' -f1)
            wantedsymbol=$(echo "$dependency" | cut -d'(' -f2 | cut -d')' -f1)
            depinfo=$(take_dependency_from_path "$rpmfile" "$goboLibraries/$libname" "$wantedsymbol")
            if [ "$depinfo" ]
            then echo "$depinfo"
            else echo "# Unresolved path-based library dependency: $dependency"
            fi
        elif is_basic_symbol "$dependency"
        then
            Log_Verbose "Skipping basic symbol: $dependency"
        elif is_rpmlib_symbol "$dependency"
        then
            Log_Verbose "Skipping internal symbol: $dependency"
        elif is_inputfile "$dependency"
        then
            Log_Verbose "Skipping dependency passed as input file: $dependency"
        else
            depinfo=$(lookup_pkgname "$dependency")
            if [ "$depinfo" ]
            then echo "$depinfo"
            else echo "# Unresolved dependency: $dependency"
            fi
        fi
    done
}

function populate_resources() {
    local rpmfile="$1"
    local arch=$(rpminfo --arch "$rpmfile")
    local description=$(rpminfo --description "$rpmfile")
    local release=$(rpminfo --release "$rpmfile")
    local distro=$(rpminfo --distribution "$rpmfile")
    
    Log_Normal "Populating Resources."
    mkdir -p Resources

    if [ "$arch" ]
    then echo "$arch"       > Resources/Architecture
    else echo "$(uname -m)" > Resources/Architecture
    fi
    echo "$release"         > Resources/Revision

    # Note that we never truncate neither Resources/PackageSource nor
    # Resources/Description or Resources/Dependencies. This is to
    # enable the installation of multiple RPM files under the same
    # /Programs entry while keeing metadata of all the original files
    # around.

    [ -e Resources/PackageSource ] && echo >> Resources/PackageSource
    echo "[File] $(basename $rpmfile)"     >> Resources/PackageSource
    echo "[Distribution] $distro"          >> Resources/PackageSource

    if [ "$description" ]
    then
        [ -e Resources/Description ] && echo ""                >> Resources/Description
        echo "[Name] $(rpminfo --name $rpmfile)"               >> Resources/Description
        echo "[Summary] $(rpminfo --summary $rpmfile)"         >> Resources/Description
        echo "[License] $(rpminfo --license $rpmfile)"         >> Resources/Description
        echo "[Description] $(rpminfo --description $rpmfile)" >> Resources/Description
        echo "[Homepage] $(rpminfo --url $rpmfile)"            >> Resources/Description
    fi

    Log_Normal "Processing dependencies."
    alldeps=$(mktemp InstallPackage-RPM.XXXXXXXXXX)
    populate_dependencies "$rpmfile"           >> Resources/Dependencies
    cat Resources/Dependencies | sort -n | uniq > "$alldeps"
    cat "$alldeps"                              > Resources/Dependencies
    rm -f -- "$alldeps"
}

function lookup_symbol() {
    local depname="$1"
    local testversion="$2"
    local arch="$3"
    local symbol="$4"
    local testarch=$(cat "$goboPrograms/$depname/$testversion/Resources/Architecture" 2> /dev/null)

    if [ "$testarch" ] && [ "$testarch" = "$arch" ]
    then
        Log_Verbose "Looking for symbol $symbol on $goboPrograms/$depname/$testversion/$path"
        if nm "$goboPrograms/$depname/$testversion/$path" 2> /dev/null | grep --max-count=1 -q "$symbol"
        then
            Log_Verbose "Match: $depname $testversion"
            echo "$depname $testversion"
            return 0
        fi
    fi
    return 1
}

function take_dependency_from_path() {
    # TODO since $2 may come in the form '/usr/lib/libfoo >= version', we have to pick the
    # path from the first part of the string. Right now we're using awk to get it, but that
    # will not work if the dependency path contains spaces.

    local rpmfile="$1"
    local originalpath=$(echo "$2" | awk '{print $1}')
    local path=$(echo "$originalpath" | sed 's,/usr,,g')
    local symbol="$3"
    local fullpath="$(readlink -f $path)"
    local arch=$(rpminfo --arch "$rpmfile")
    local distro=$(rpminfo --distribution "$rpmfile")

    local depname=
    local depversion=

    if echo "$fullpath" | grep -q "^${goboPrograms}"
    then
        # If given, we search for the presence of @symbol on the given target file.
        # We iterate over different installations of the same program looking for
        # that symbol. If none of the installations have it, we fallback to printing
        # the dependency currently linked on /System/Index.
        #
        # Note that when iterating over installed programs we skip those entries whose
        # Resources/Architecture do not match the output of $(rpminfo --arch).

        depname=$(echo "$fullpath" | cut -d/ -f3)
        depversion=$(echo "$fullpath" | cut -d/ -f4)
        if [ "$symbol" ]
        then
            for testversion in $(ls $goboPrograms/$depname/ | grep -v "Settings\|Variable\|Current")
            do
                lookup_symbol "$depname" "$testversion" "$arch" "$symbol" && return 0
            done
        fi

        Log_Verbose "Fallback: $depname $depversion"
        echo "$depname $depversion"
    else
        # We have a path, but we don't have a link to that file under /System/Index.
        # Our first attempt is to search over the list of installed programs anyhow,
        # because some programs may not be currently activated.

        for fullpath in $(ls $goboPrograms/*/*/$path 2> /dev/null | grep -v "Current")
        do
            depname=$(echo "$fullpath" | cut -d/ -f3)
            testversion=$(echo "$fullpath" | cut -d/ -f4)
            [ -z "$depversion" ] && depversion="$testversion"
            Log_Verbose "Looking for symbol on candidate file $candidate ($depname, $testversion)"
            lookup_symbol "$depname" "$testversion" "$arch" "$symbol" && return 0
        done

        # We don't have a match. If we have a file name that satisfies the path but
        # that doesn't contain the requested symbol, we simply return that path.

        if [ "$depname" ] && [ "$depversion" ]
        then
            echo "$depname $depversion"
            return 0
        fi

        # We don't have a matching filename under /System/Index nor under /Programs/*/*.
        # What we do now is to query remote RPM databases to find which package hosts the
        # dependency file.

        if ! Boolean "no-web"
        then
            Log_Normal "Searching the remote RPM database for the package hosting $originalpath"
            depname=$(RPMFinder --path="$originalpath" --arch="$arch" --distro="$distro")
            if [ "$depname" ]
            then
                # TODO: we could now lookup the GoboLinux recipe store to find whether we
                # have it or not
                echo "$(GuessProgramCase $depname)"
                return 0
            fi
        fi
    fi
}

function lookup_pkgname() {
    local dependency="$1"
    local pkgname=$(echo "$dependency" | cut -d'(' -f1)

    # Do we have a GoboLinux package installed with a matching name?
    for testname in $(ls $goboPrograms/)
    do
        # Case-insensitive comparison (requires Bash 4)
        if [ "${testname,,}" = "${pkgname,,}" ]
        then
            echo "$pkgname" && return 0
        fi
    done

    # Query the remote RPM database
    return 1
}

function is_basic_symbol() {
    local dependency="$1"
    echo "$dependency" | grep -q "^rtld("  && return 0
    return 1
}

function is_rpmlib_symbol() {
    local dependency="$1"
    echo "$dependency" | grep -q "^VersionedDependencies"  && return 0
    echo "$dependency" | grep -q "^PayloadFilesHavePrefix" && return 0
    echo "$dependency" | grep -q "^CompressedFileNames"    && return 0
    echo "$dependency" | grep -q "^PayloadIs"              && return 0
    return 1
}

function deduce_program_name() {
    local rpmfile="$1"
    local name=$(rpminfo --name "$rpmfile")
    echo $name
}

function prepare_program_entry() {
    local rpmfile="$1"

    if [ ${#rpmfiles[@]} -gt 1 ] && Is_Entry "app-name" && [ ! -z "$programname" ]
    then
        # We have already prepared this program's entry on /Programs
        return
    fi
    if Is_Entry "app-name"
    then programname=$(Entry "app-name")
    else programname="$(deduce_program_name $rpmfile)"
    fi
    if Is_Entry "version-number"
    then programversion=$(Entry "version-number")
    else programversion=$(printf "%s_%s" $(rpminfo --version "$rpmfile") $(rpminfo --release "$rpmfile"))
    fi

    # Prepare /Programs tree and update program name (PrepareProgram may have changed its case)
    PrepareProgram -t "$programname" "$programversion"
    programname=$(ls $goboPrograms/ | grep -i "^${programname}$")
    target="$goboPrograms/$programname/$programversion"
}

### Operation #################################################################

Is_Writable "${goboPrograms}" || Verify_Superuser

if Boolean "verbose"
then verbose="--verbose"
else verbose=
fi

# The rpmfiles array holds the full path of all RPM input files
# The rpmnames array holds the package name of all RPM input files
rpmfiles=()
rpmnames=()
eval `Args_To_Array rpmfiles_`
for entry in "${rpmfiles_[@]}"
do
    rpmfiles+=( "$(readlink -f ${entry} || echo ${entry})" )
    rpmnames+=( "$(rpminfo --name $entry)" )
done

# These will be set by prepare_program_entry()
unset programname
unset programversion
unset target

# Determine the flattening level of /opt. In other words, whether
# we have something like:
# /opt/pkgname/{bin,sbin...}            (1-level), or
# /opt/vendorname/pkgname/{bin,sbin...} (2-level)

flatteninglevel=$(determine_flattening_level)

# Installation pipeline
for entry in "${rpmfiles[@]}"
do
    Log_Normal "Processing $(basename $entry)"
    rpmfile=$(fetch_rpm "$entry")
    prepare_program_entry "$rpmfile"
    Quiet pushd "$target" || Die "Could not enter $target"

    uncompress_rpm "$rpmfile"
    flatten_rpm "$rpmfile"
    populate_resources "$rpmfile"

    Quiet popd
    Is_URL "$entry" && rm -f -- "$rpmfile"
done

# Symlinking
if [ $(Entry "symlink") = "no" ]
then
    Log_Normal "Done."
    exit 0
fi

[ -d "$target/Resources/Defaults/Settings" ] && UpdateSettings "$programname" "$programversion"
SymlinkProgram "$programname" "$programversion"
Log_Normal "Done."