#!/usr/bin/env bash
# ~/bin/sdr-heat-scanner - Wireless M-Bus & Heat Meter SDR Telemetry Collector
# Listens on 868.95 MHz (Mode C&T) and 868.3 MHz (Mode S) using RTL-SDR / rtl_433.
# Part of The Observatoř environmental telemetry suite.

set -euo pipefail

DATA_DIR="$HOME/src/observator/data"
LOG_FILE="$DATA_DIR/heat_meters.jsonl"
SHM_FILE="/dev/shm/latest_heat_meter.json"
PID_FILE="/tmp/sdr-heat-scanner.pid"

mkdir -p "$DATA_DIR"

cmd="${1:-scan}"

case "$cmd" in
    start)
        if [ -f "$PID_FILE" ] && kill -0 "$(cat "$PID_FILE")" 2>/dev/null; then
            echo "[sdr-heat] Scanner already running (PID: $(cat "$PID_FILE"))."
            exit 0
        fi

        echo "[sdr-heat] Starting RTL-SDR heat meter scanner daemon (868.95 MHz Mode C&T)..."
        # Run rtl_433 in background appending JSON lines
        nohup rtl_433 -f 868.95M -s 1200k -R 104 -F json >> "$LOG_FILE" 2>/tmp/sdr-heat.err &
        SCAN_PID=$!
        echo "$SCAN_PID" > "$PID_FILE"
        echo "[sdr-heat] Scanner started with PID $SCAN_PID, logging to $LOG_FILE"
        ;;

    stop)
        if [ -f "$PID_FILE" ]; then
            PID=$(cat "$PID_FILE")
            if kill -0 "$PID" 2>/dev/null; then
                kill "$PID" 2>/dev/null || true
                echo "[sdr-heat] Stopped scanner daemon (PID: $PID)."
            fi
            rm -f "$PID_FILE"
        else
            pkill -f "rtl_433 -f 868.95M" 2>/dev/null || true
            echo "[sdr-heat] Stopped all rtl_433 instances."
        fi
        ;;

    status)
        if [ -f "$PID_FILE" ] && kill -0 "$(cat "$PID_FILE")" 2>/dev/null; then
            echo "[sdr-heat] Scanner DAEMON ACTIVE (PID: $(cat "$PID_FILE"))"
        else
            echo "[sdr-heat] Scanner DAEMON INACTIVE"
        fi
        
        if [ -f "$LOG_FILE" ]; then
            TOTAL_PACKETS=$(wc -l < "$LOG_FILE")
            echo "[sdr-heat] Total captured packets: $TOTAL_PACKETS"
            echo "[sdr-heat] Unique meter IDs detected:"
            grep -oP '"id":\s*\K[0-9]+' "$LOG_FILE" | sort -u | head -n 10 || echo "None yet"
        else
            echo "[sdr-heat] Log file $LOG_FILE not yet created."
        fi
        ;;

    view|tail)
        if [ -f "$LOG_FILE" ]; then
            tail -f "$LOG_FILE"
        else
            echo "[sdr-heat] No packets logged yet in $LOG_FILE."
        fi
        ;;

    scan|live)
        echo "[sdr-heat] Starting live foreground scan on 868.95 MHz (Ctrl+C to stop)..."
        exec rtl_433 -f 868.95M -s 1200k -R 104
        ;;

    *)
        echo "Usage: sdr-heat-scanner <start|stop|status|scan|view>"
        exit 1
        ;;
esac