#!/usr/bin/env bash

# A version number is defined by:  MAJOR.MINOR.PATCH
# where
#     MAJOR version when you make incompatible API changes
#     MINOR version when you add functionality in a backwards-compatible manner, and
#     PATCH version when you make backwards-compatible bug fixes.
# See also Issue #109
#
# bumps version number of project
# change 1 line (VERSION) in "Cargo.toml"
# creates 1-line `VERSION` file
#
# the script must take 1 argument: either `--mayor`, `--minor` or `--patch`
# NO default is set on purpose.

FN="Cargo.toml"
VERSION_FILE="VERSION"
UPDATE="invalid"

if ! [ -f "$FN" ]; then
    FN="../$FN"
    if ! [ -f "$FN" ]; then
        echo -n "ERROR: $(basename -- "$FN") not found. "
        echo "Neither in local nor in parent directory."
        exit 1
    fi
fi

if ! [ -f "$FN" ]; then
    echo "ERROR: File \"$FN\" not found."
    exit 1
fi

if [ "${1,,}" == "-ma" ] || [ "${1,,}" == "--mayor" ]; then
    UPDATE="MAYOR"
fi

if [ "${1,,}" == "-mi" ] || [ "${1,,}" == "--minor" ]; then
    UPDATE="MINOR"
fi

if [ "${1,,}" == "-p" ] || [ "${1,,}" == "--patch" ]; then
    UPDATE="PATCH"
fi


if [ "${UPDATE,,}" == "invalid" ]; then
    echo "Error: No version type specified: specify either '--mayor', '--minor' or '--patch'."
    exit 2
fi

echo "Doing a ${UPDATE} version increment."


PREFIX="version = "
REGEX="^${PREFIX}\"[0-9][0-9]*\.[0-9][0-9]*\.[0-9][0-9]*\""
COUNT=$(grep --count -e "$REGEX" $FN)
if [ "$COUNT" == "1" ]; then
    NR=$(grep -e "$REGEX" $FN | cut -d'"' -f2)
    A=$(echo $NR | cut -d'.' -f1)
    M=$(echo $NR | cut -d'.' -f2)
    Z=$(echo $NR | cut -d'.' -f3)
    if [ "$UPDATE" == "MAYOR" ]; then
        A=$((A + 1))
        M="0"
        Z="0"
    elif [ "$UPDATE" == "MINOR" ]; then
        M=$((M + 1))
        Z="0"
    else
        Z=$((Z + 1))
    fi
    NEWVERSIONNR="${A}.${M}.${Z}"
    echo $NEWVERSIONNR >"$VERSION_FILE"
    NEWVERSION="$PREFIX\"${A}.${M}.${Z}\""
    sed -i "s/$REGEX/$NEWVERSION/" $FN
    RETURN=$?
    if [ "$RETURN" == "0" ]; then
        echo "SUCCESS: Modified file $FN by setting version to $NEWVERSION."
    else
        echo "ERROR: could not change version to $NEWVERSION in $FN."
        exit 1
    fi
else
    echo "Error while searching for $REGEX"
    grep -e "$PREFIX" $FN
    if [ "$COUNT" == "1" ]; then
        echo "ERROR: Version not found in $FN, expected 1 occurance."
    else
        echo "ERROR: Version found $COUNT times in $FN, expected 1 occurance."
    fi
    exit 1
fi

exit 0