irc-atom-notice-wiki

#! /usr/bin/env bash

# © 2022 Unvanquished Developers
# MIT License https://spdx.org/licenses/MIT.html

export shell_opts="${shell_opts:--u -e -o pipefail}"
set ${shell_opts}

export slug='wiki'
export atom_url='https://wiki.unvanquished.net/api.php?hidebots=1&days=1&limit=10&action=feedrecentchanges&feedformat=atom'

script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"
cd "${script_dir}"

script_name="$(basename "${BASH_SOURCE[0]}")"

. 'irc-atom-notice.conf'

case "${1:-}" in
	'-h'|'--help')
		printf '%s <interval-in-seconds>\n' "${script_name}"
		exit
		;;
	[0-9][0-9]*)
		interval="${1}"
		;;
esac

export interval

colorString () {
	set ${shell_opts}

	local color="${1}"; shift
	local string="${1}"; shift
	printf '\x03%s%s\x0f' "${color}" "${string}"
}

export -f colorString

processEntry () {
	set ${shell_opts}

	local entry="${1}"

	local date
	local url
	local nick
	local title

	printf '%s\n' "${entry}" \
	| tr '\t' '\n' \
	| while read date
	do
		read url
		read nick
		read title

		title="$(printf '%s' "${title}" | html2text -nobs -utf8 -width 999 | head -n1)"

		local tag="${slug}"
		local channel='#unvanquished-dev'

		local c_tag="$(colorString '08,15' "${tag}")"
		local c_nick="$(colorString '10' "${nick}")"
		local c_title="$(colorString '03' "${title}")"

		local message="[${c_tag}] ${c_nick} edited “${c_title}”: &lt;${url}&gt;"

		# MediaWiki already sets the Z UTC suffix.
		local commit_epoch="$(date --date="${date}" '+%s')"
		local current_epoch="$(date '+%s')"

		local entry_age="$((${current_epoch} - ${commit_epoch}))"
		local purgatory_time="$((${interval} / 60))"

		if [ "${purgatory_time}" -lt 5 ]
		then
			purgatory_time=5
			if [ "${purgatory_time}" -gt "${interval}" ]
			then
				purgatory_time=1
			fi
		fi

		local allowed_age="$((${interval} + ${purgatory_time}))"

		if [ "${entry_age}" -le "${allowed_age}" ]
		then
			log_date="$(date --rfc-3339=s --utc --date="@${commit_epoch}")"
			cat >> "${log_file}" <<-EOF
			"${log_date}: ${MSGCMD:-./irc-msg} "${channel}" "${message}"
			EOF
			${MSGCMD:-./irc-msg} "${channel}" "${message}"
		fi
	done
}

export -f processEntry

mkdir -p "${cache_dir}"

before_tsv="${cache_dir}/${slug}-before.tsv"
current_tsv="${cache_dir}/${slug}-current.tsv"
current_atom="${cache_dir}/${slug}-current.atom"

mkdir -p "${log_dir}"
export log_file="${log_dir}/${slug}.log"

touch "${log_file}"

touch "${current_tsv}"
mv "${current_tsv}" "${before_tsv}"

curl -s "${atom_url}" > "${current_atom}"

# The TSV file may not be produced if the Atom feed doesn't have any entry.
# The MediaWiki Atom feed doesn't have a published date field, only an updated date one. We track Wiki editions anyway.
xsltproc --nonet --output "${current_tsv}" 'atom-tsv-updated.xslt' "${current_atom}"
touch "${current_tsv}"

sort "${current_tsv}" -o "${current_tsv}"

comm -1 -3 "${before_tsv}" "${current_tsv}" \
| tr '\n' '\0' \
| xargs -0 -r -n1 -P1 \
	/usr/bin/env bash ${shell_opts} -c 'processEntry "${@}"' processEntry