#!/bin/bash
# notify-telegram.sh — send a message to the configured Telegram chat.
# Sources credentials from $ALEMBIC_CONFIG_DIR/pipeline/telegram/notify.env (chmod 600).
#
# Usage:
#   echo "single line message" | notify-telegram.sh
#   notify-telegram.sh "single line message"
#   notify-telegram.sh < ${ALEMBIC_CONFIG_DIR:-/config}/logs/STATUS.log
#
# Telegram messages are capped at 4096 chars. Anything longer is truncated
# with a "...<truncated>" tail. Returns exit 0 on send-OK, non-zero otherwise.

set -euo pipefail
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

CONFIG="${ALEMBIC_CONFIG_DIR:-/config}/pipeline/telegram/notify.env"
if [[ ! -f "$CONFIG" ]]; then
  echo "[notify-telegram] no config at $CONFIG" >&2
  exit 1
fi
# shellcheck disable=SC1090
source "$CONFIG"
: "${TG_BOT_TOKEN:?TG_BOT_TOKEN missing}"
: "${TG_CHAT_ID:?TG_CHAT_ID missing}"

# Read message from arg or stdin
if [[ $# -ge 1 ]]; then
  MSG="$*"
else
  MSG=$(cat)
fi

# Telegram caps at 4096 chars (UTF-8 codepoints). Trim conservatively at 3900.
# Use python for proper UTF-8 length handling.
MSG=$(python3 -c "
import sys
s = sys.argv[1]
if len(s) > 3900:
    s = s[:3900] + '\n...<truncated>'
print(s, end='')
" "$MSG")

# Send via Bot API. Disable web-page preview and use plain text (no parse_mode)
# so log content with special chars doesn't get interpreted as Markdown.
# `|| true`: a curl timeout/network error must fall through to the explicit
# ok-check below (which reports "send failed" and exits 2), not abort here.
resp=$(curl -s --max-time 15 -X POST \
  "https://api.telegram.org/bot${TG_BOT_TOKEN}/sendMessage" \
  --data-urlencode "chat_id=${TG_CHAT_ID}" \
  --data-urlencode "text=${MSG}" \
  --data-urlencode "disable_web_page_preview=true" || true)

ok=$(echo "$resp" | python3 -c "import sys,json;print(json.load(sys.stdin).get('ok',False))" 2>/dev/null || echo False)
if [[ "$ok" != "True" ]]; then
  echo "[notify-telegram] send failed: $resp" >&2
  exit 2
fi
exit 0