#!/bin/bash
# devdesk-notify-matrix SESSION SINCE
#
# Started (detached) by devdesk-state-hook when a session starts waiting on you.
# After DEVDESK_MATRIX_DELAY seconds, if that same wait is still on and nobody is
# attached to the session (no browser tab, no SSH client), post one "Claude needs
# you" message to the hookshot webhook in DEVDESK_MATRIX_WEBHOOK_FILE (devdesk#28).
set -euo pipefail

# shellcheck source=libexec/devdesk-lib.sh
. "${DEVDESK_LIBEXEC:-/usr/lib/devdesk}/devdesk-lib.sh"

session=${1:-}
since=${2:-}
dd_valid_name "$session" || exit 0
[[ $since =~ ^[0-9]+$ ]] || exit 0
[ -r "$DEVDESK_MATRIX_WEBHOOK_FILE" ] || exit 0

sleep "$DEVDESK_MATRIX_DELAY"

state_file="$DEVDESK_STATUS_DIR/$session.json"
# Still the same wait? (Answering it moves the state on; a new wait has its own notifier.)
[ "$(jq -rM '"\(.state) \(.since)"' "$state_file" 2>/dev/null)" = "waiting $since" ] || exit 0
# Anyone looking at it already?
attached=$(dd_tmux list-sessions -F '#{session_name} #{session_attached}' 2>/dev/null |
    awk -v s="$session" '$1 == s { print $2 }')
[ "${attached:-0}" = 0 ] || exit 0

message=$(jq -rM '.message // "Claude is waiting for your input"' "$state_file" 2>/dev/null)
detail=$(jq -rM '.request.detail // empty' "$state_file" 2>/dev/null)
[ -z "$detail" ] || message="$message: ${detail:0:300}"
url=""
# existing=1: if the session was ended by the time you tap, say so instead of
# starting a new Claude there (devdesk#38).
[ -z "$DEVDESK_PUBLIC_URL" ] || url="${DEVDESK_PUBLIC_URL%/}/?arg=$session&existing=1"
body=$(jq -cMn --arg s "$session" --arg m "$message" --arg u "$url" --arg h "$(hostname)" \
    '{session: $s, message: $m, url: (if $u == "" then null else $u end), host: $h,
      text: ("Claude needs you in " + $s + ": " + $m + (if $u == "" then "" else " — " + $u end))}')

# The webhook URL is a secret (anyone holding it can post to the room): pass it
# to curl on stdin, never on the command line.
# shellcheck disable=SC1003 # tr deletes whitespace, quotes and backslashes from the URL
webhook=$(tr -d '[:space:]"\\' <"$DEVDESK_MATRIX_WEBHOOK_FILE")
printf 'url = "%s"\n' "$webhook" |
    curl -fsS --max-time 10 --retry 2 -K - -H 'Content-Type: application/json' --data-binary "$body" >/dev/null