#!/bin/bash

# Copyright 2017 Intel Corporation.
#
# Licensed 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.

# VSPERF code checker

PYLINT="pylint"
PYLINT_RC='pylintrc'
PYLINT_RATING_GATE="10"
PYLINT_RATING_MIN=$PYLINT_RATING_GATE
FILE_REGEX="(^vsperf|\.py)$"
FILE_LIST="/tmp/vsperf_check_list.txt"
BC=`which bc`

# print usage if requested
function usage() {
    cat <<EOM
Usage: $0 [TARGET]...

Performs code check for defined TARGETs. Target can be file or directory.
In case that directory is specified, then it will be searched recursively
for all python files.
If TARGET is not specified, then all python files from current VSPERF
repository will be checked.
Files listed in EXCLUDE_MODULES defined in conf/00_common.conf will be skipped.
File will pass check if its pylint rating is greater or equal to $PYLINT_RATING_GATE.
Otherwise gained pylint rating will be displayed.


    -h, --help                  Script usage
    -b, --black                 Suppress colours. Output will be black&white.
    -m, --modified              Script will check python files, which have
                                been modified within current repository.

Examples:
    ./check

    Check all python files in current VSPERF repository except EXCLUDE_MODULES

    ./check vsperf

    Check just one file.

    ./check -m

    Check all modified files in current VSPERF repository

    ./check vnfs/qemu core tools/pkt_gen

    Check all python files in given directories

EOM
}

# compare pylint result with predefined gate
function rating_is_ok() {
    # bc is not part of basic Centos installation
    # so let us check if it is available
    if [ "x$BC" == "x" ] ; then
        # no bc, so do integer comparison only
        int_rating=`echo $1 | sed -e 's/\..*$//'`
        int_rating_min=`echo $PYLINT_RATING_MIN | sed -e 's/\..*$//'`
        [ $int_rating -lt $int_rating_min ] && PYLINT_RATING_MIN=$int_rating
        if [ $int_rating -lt $PYLINT_RATING_GATE ] ; then
            return 1
        else
            return 0
        fi
    else
        if (( $(echo "$1<$PYLINT_RATING_MIN" | bc -l) )) ; then
            PYLINT_RATING_MIN=$1
        fi
        if (( $(echo "$1<$PYLINT_RATING_GATE" | bc -l) )) ; then
            return 1
        else
            return 0
        fi
    fi
}

##### MAIN #####
# check if help is requested
if [ "x$1" == "x-h" -o "x$1" == "x--help" ] ; then
    usage
    exit 0
fi

# set colours
if [ "x$1" == "x-b" -o "x$1" == "x--black" ] ; then
    shift
    RED=""
    GREEN=""
    BLACK=""
else
    RED="\e[31m"
    GREEN="\e[32m"
    BLACK="\e[0m"
fi


# check if pylint is available
if ! which $PYLINT &>/dev/null ; then
    echo "$PYLINT is not available, thus check can't be executed"
    exit 1
fi

# check if we were run within vsperf directory
if [ ! -x ./vsperf 2> /dev/null ] ; then
    echo "`basename $0` must be run from vsperf root directory"
    exit 2
fi

# get list of excluded modules
EXCLUDED_MODULES=`grep "^ *EXCLUDE_MODULES" conf/00_common.conf | tr '"' "'"`

# get list of files to be checked
rm $FILE_LIST &> /dev/null
if [ "x$1" == "x-m" -o "x$1" == "x--modified" ] ; then
    # check of modified files requested
    git status --porcelain | cut -b4- | egrep -i "${FILE_REGEX}" | sort > $FILE_LIST
elif [ "x$*" == "x" ] ; then
    # list is empty, check all python files
    git ls-tree --name-only -r HEAD | egrep -i "${FILE_REGEX}" | sort > $FILE_LIST
else
    for item in $* ; do
        if [ -d $item ] ; then
            git ls-tree --name-only -r HEAD $item | egrep -i "${FILE_REGEX}" | sort >> $FILE_LIST
        elif [ -f $item ] ; then
            echo $item >> $FILE_LIST
        else
            echo "$item doesn't exist, thus check was aborted"
            exit 3
        fi
    done
fi

# check if there is anything to check
echo "Execution of pylint checks:"
if [ -s $FILE_LIST ] ; then
    for pyfile in `cat $FILE_LIST | sort` ; do
        # get base name
        pyfile_basename="'"`basename $pyfile .py`"'"
        # and check if it should be excluded or not
        if ( echo $EXCLUDED_MODULES | grep -w $pyfile_basename > /dev/null ) ; then
            printf "    %-70s %-6s\n" $pyfile "EXCLUDED"
            continue
        fi
        # run pylint and extract final rating
        output=`$PYLINT --rcfile $PYLINT_RC $pyfile 2>/dev/null`
        rating=`echo -e $output | tail -n3 | grep rated | sed -e 's/^.*rated at \(-\?[0-9.]*\).*$/\1/'`
        # evaluate and display aquired rating
        if [ "x$rating" == "x" ] ; then
            # rating is not available for files without python statements
            printf "    %-70s %-6s\n" $pyfile "NA"
        elif rating_is_ok $rating ; then
            printf "    %-70s ${GREEN}%-6s${BLACK}\n" $pyfile "OK"
        else
            echo -e "$output" | awk '/^\*+ Module|^[A-Z]\:/'
            printf "    %-70s ${RED}%-6s${BLACK}\n" $pyfile $rating
        fi
    done
else
    echo "Nothing to check."
    exit 4
fi

# clean up
rm $FILE_LIST &> /dev/null

if [ "$PYLINT_RATING_MIN" != "$PYLINT_RATING_GATE" ] ; then
    echo -e "Pylint check has failed. All files must have score ${PYLINT_RATING_GATE}.\n"
    exit 1
else
    exit 0
fi
##### MAIN end #####