#!/usr/bin/env bash
# start-whetstone-daemon.sh
#
# Ensures a single whetstone_mcp HTTP+SSE daemon is running on port 7600.
# Safe to call multiple times — exits immediately if already running.
#
# Usage:
#   ./tools/start-whetstone-daemon.sh
#   ./tools/start-whetstone-daemon.sh --port 7601
#   ./tools/start-whetstone-daemon.sh --language python
#
# Output: prints daemon PID on stdout.

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
WHETSTONE_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
BINARY="$WHETSTONE_DIR/editor/build-native/whetstone_mcp"
WORKSPACE="$WHETSTONE_DIR"
PORT=7600
LANGUAGE="cpp"
LOG="$WHETSTONE_DIR/.whetstone/daemon.log"
PID_FILE="$WHETSTONE_DIR/.whetstone/daemon.pid"

# Parse optional overrides
while [[ $# -gt 0 ]]; do
    case "$1" in
        --port)     PORT="$2";     shift 2 ;;
        --language) LANGUAGE="$2"; shift 2 ;;
        *) echo "Unknown arg: $1" >&2; exit 1 ;;
    esac
done

# Check if daemon is already running
if [[ -f "$PID_FILE" ]]; then
    EXISTING_PID=$(cat "$PID_FILE" 2>/dev/null || echo "")
    if [[ -n "$EXISTING_PID" ]] && kill -0 "$EXISTING_PID" 2>/dev/null; then
        echo "[whetstone-daemon] Already running (PID $EXISTING_PID)" >&2
        echo "$EXISTING_PID"
        exit 0
    fi
fi

# Also check by port
if lsof -ti :"$PORT" >/dev/null 2>&1; then
    echo "[whetstone-daemon] Port $PORT already in use — daemon may be running" >&2
    lsof -ti :"$PORT"
    exit 0
fi

if [[ ! -x "$BINARY" ]]; then
    echo "[whetstone-daemon] Binary not found: $BINARY" >&2
    echo "[whetstone-daemon] Build it with: cmake --build editor/build-native --target whetstone_mcp --parallel" >&2
    exit 1
fi

mkdir -p "$WHETSTONE_DIR/.whetstone"

# Start daemon in background
nohup "$BINARY" \
    --daemon \
    --port "$PORT" \
    --workspace "$WORKSPACE" \
    --language "$LANGUAGE" \
    > "$LOG" 2>&1 &

DAEMON_PID=$!

# Wait briefly for daemon to write its PID file and start listening
for i in $(seq 1 20); do
    sleep 0.25
    if curl -sf "http://127.0.0.1:$PORT/health" >/dev/null 2>&1; then
        echo "[whetstone-daemon] Started (PID $DAEMON_PID, port $PORT)" >&2
        echo "$DAEMON_PID"
        exit 0
    fi
done

echo "[whetstone-daemon] WARNING: daemon started (PID $DAEMON_PID) but /health not yet responding" >&2
echo "$DAEMON_PID"