#!/usr/bin/env bash
# gstack-brain-enqueue — atomically append a path to the GBrain sync queue.
#
# Usage:
#   gstack-brain-enqueue <file-path>
#
# Called by writer scripts (gstack-learnings-log, gstack-timeline-log, etc.)
# after their local write. Fire-and-forget; failures are silent (never blocks
# the writer). Queue is drained by `gstack-brain-sync --once` invoked from the
# preamble at skill START and END boundaries.
#
# No-op when:
#   - artifacts_sync_mode is off (the default)
#   - ~/.gstack/.git doesn't exist (feature not initialized)
#   - <file-path> matches a line in ~/.gstack/.brain-skip.txt
#
# Env:
#   GSTACK_HOME — override ~/.gstack state directory (aligns with writers).
#                 Tests use GSTACK_HOME=/tmp/test-$$ for isolation.
#
# Concurrency: POSIX append is atomic up to PIPE_BUF (~4KB Linux, 512 BSD).
# Queue lines are ~200 bytes, safe under concurrent callers.

# No `-e` — writer shims rely on this never failing loudly.
set -uo pipefail

FILE="${1:-}"
[ -z "$FILE" ] && exit 0

GSTACK_HOME="${GSTACK_HOME:-$HOME/.gstack}"
QUEUE="$GSTACK_HOME/.brain-queue.jsonl"
SKIP_FILE="$GSTACK_HOME/.brain-skip.txt"

# Fast exits: no git repo, no sync.
[ ! -d "$GSTACK_HOME/.git" ] && exit 0

# Check sync mode. off → silent no-op.
SCRIPT_DIR="$(cd "$(dirname "$0")" 2>/dev/null && pwd)"
MODE=$("$SCRIPT_DIR/gstack-config" get artifacts_sync_mode 2>/dev/null || echo off)
[ "$MODE" = "off" ] && exit 0

# User-maintained skip list (for secret-scan false positives).
if [ -f "$SKIP_FILE" ]; then
  if grep -Fxq "$FILE" "$SKIP_FILE" 2>/dev/null; then
    exit 0
  fi
fi

# JSON-escape the file path (backslash + quotes only; paths shouldn't have other specials).
ESC_FILE=$(printf '%s' "$FILE" | sed 's/\\/\\\\/g; s/"/\\"/g')
TS=$(date -u +%Y-%m-%dT%H:%M:%SZ 2>/dev/null || echo "")

printf '{"file":"%s","ts":"%s"}\n' "$ESC_FILE" "$TS" >> "$QUEUE" 2>/dev/null

exit 0
