package

#!/bin/bash

# Usage info
show_help() {
cat << EOF
Usage: [-hf] [-v <git tag>]

Parameter details:
    -h display help and exit
    -v git tag, checkout release tag specified
EOF
}

# Initialise variables
OPTIND=1 # Reset for previous uses of getops in shell
OPTSTRING="hv:"
gitTag=false
cd "$( dirname "${BASH_SOURCE[0]}" )" # cd into directory the script is inside
confFile="package.conf"

while getopts "$OPTSTRING" opt; do
    case "$opt" in
    h)
        show_help
        exit 0
        ;;
    v)
        gitTag=$OPTARG
        ;;
    *)
        show_help >&2
        exit 1
        ;;
    esac
done

# Arg1 is the text, arg2 is the file path
function prepend_text_to_file {
    echo -e "$1$(cat $2)" > $2
}

if [[ -f "$confFile" ]]; then
    # takes values from conf file and converts them into bash variables
    source $confFile
else
    echo "$confFile not found"
    exit 1
fi

# Validation
if [[ ! -f "$changelog_file_path" ]]; then
    echo "$changelog_file_path is not a file"
fi

if [[ ! -d "$unreleased_changes_directory_path" ]]; then
    echo "$unreleased_changes_directory_path is not a directory"
fi

if [[ "$(ls -1 "$unreleased_changes_directory_path" | wc -l)" == 0 ]]; then
    echo "changes directory is empty"
    exit 1
fi

# Append tag and date to changelog
echo "Adding to $changelog_file_path"

newChange="\\\t<release>\n\t\t<meta>\n\t\t\t<tag>$gitTag</tag>\n\t\t\t<date>$(date +"%y-%m-%d")</date>\n\t\t</meta>\n"

# Iterate over files by globbing
for filepath in "$unreleased_changes_directory_path"*; do
    # avoid glob not matching
    [ -e "$filepath" ] || continue

    # read file line by line
    # -r prevents backslash escapes from being interpreted.
    # || [[ -n $line ]] prevents the last line from being ignored if it doesn't end with a \n (since read returns a non-zero
    # exit code when it encounters EOF).
    while read -r line || [[ -n "$line" ]]; do

        # strips directory path prefix off of path to file to leave only the filepath
        trueFilename=${filepath#"$unreleased_changes_directory_path"}
        # add to newChange
        newChange="$newChange\t\t<change>$trueFilename - $line</change>\n"
    done < "$filepath"
done
newChange="$newChange\t</release>"

sed -i "/<changelog>/a $newChange" "$changelog_file_path"

# Remove files in $unreleased_changes_directory_path as they're now in the changelog
echo "Removing files matching $unreleased_changes_directory_path*"
rm -rf "$unreleased_changes_directory_path"*