#!/usr/bin/env bash
#
# update_issue_template_urls
#

###
### settings
###

set -e                # exit on uncaught error
set +o histexpand     # don't expand history expressions
shopt -s nocasematch  # case-insensitive regular expressions

###
### constants
###

script_subdir='developer/bin'
template_subdir='doc/issue_templates'
generate_url_script='generate_issue_template_url'
files_to_update=(README.md doc/readme.md doc/reporting_bugs/*)

###
### functions
###

warn () {
    local message="$*"
    message="${message//\\t/$'\011'}"
    message="${message//\\n/$'\012'}"
    message="${message%${message##*[![:space:]]}}"
    printf "%s\n" "$message" 1>&2
}

die () {
    warn "$@"
    exit 1
}

usage () {
    printf "update_issue_template_urls

Regenerate issue template URLs and update them in relevant files.

Note: docs using issue template URLs must use a specific format.
If the template file is called 'bug_report.md', the URL must be
referenced in the doc as follows:

  [Some link text][bug_report_template]

  ...

  [bug_report_template]: (auto-generated-url)

"
}

cd_to_project_root () {
    local script_dir git_root
    script_dir="$(/usr/bin/dirname "$0")"
    cd "$script_dir"
    git_root="$(git rev-parse --show-toplevel)"
    if [[ -z "$git_root" ]]; then
        die "ERROR: Could not find git project root"
    fi
    cd "$git_root"
}

generate_template_url () {
    local template_file="$1"
    "$script_subdir/$generate_url_script" "$template_file"
}

update_template_url () {
    local template_name="$1"
    local template_url="$2"
    local escaped_template_url="${template_url/&/\\&}"

    /usr/bin/sed -i '' \
                 -e "s|^\\(\\[${template_name}\\]: \\).*$|\\1${escaped_template_url}|g" \
                 -- "${files_to_update[@]}"
}

###
### main
###

_update_issue_template_urls () {
    local template_file template_name template_url
    cd_to_project_root
    for template_file in ./$template_subdir/*; do
        template_name="${template_file##*/}"
        template_name="${template_name%%.*}"
        template_url="$(generate_template_url "$template_file")"
        update_template_url "$template_name" "$template_url"
    done
}

# process args
if [[ $1 =~ ^-+h(elp)?$ ]]; then
    usage
    exit
fi

# dispatch main
_update_issue_template_urls