#!/usr/bin/env bash
# msg-loop.sh — reliably send a message to a loop's tmux session AND submit it.
# -------------------------------------------------------------------------
# `tmux send-keys -l <long message>` frequently leaves the text sitting UNSENT in
# the input box (the immediate Enter is swallowed while the TUI is still ingesting
# the paste). This types the message, then retries Enter/C-m until the text is no
# longer in the input box (= it was submitted), or gives up after a bounded loop.
#
#   msg-loop.sh <tmux-session> <message...>
# exit 0 = delivered; 2 = could not confirm submit; 1 = bad args / no session.
set -uo pipefail

S="${1:?usage: msg-loop.sh <session> <message...>}"; shift
MSG="$*"
[ -n "$MSG" ] || { echo "msg-loop: empty message"; exit 1; }
tmux has-session -t "$S" 2>/dev/null || { echo "msg-loop: no tmux session '$S'"; exit 1; }

PREFIX="$(printf '%s' "$MSG" | head -c 28)"
# Submitted ⇔ the message's leading text is no longer in the input box (bottom of the pane).
in_input_box() { tmux capture-pane -pt "$S" 2>/dev/null | tail -4 | grep -qF -- "$PREFIX"; }

tmux send-keys -t "$S" -l -- "$MSG" 2>/dev/null || { echo "msg-loop: send-keys failed"; exit 1; }
sleep 0.8
for _ in 1 2 3 4 5 6 7 8 9 10; do
  tmux send-keys -t "$S" Enter 2>/dev/null || true
  sleep 1.2
  in_input_box || { echo "$S: delivered ✔"; exit 0; }
  tmux send-keys -t "$S" C-m 2>/dev/null || true   # some TUI states take C-m not Enter
  sleep 0.8
  in_input_box || { echo "$S: delivered ✔"; exit 0; }
done
echo "$S: WARNING — could not confirm submit; message may remain in the input box"
exit 2