import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.actuate.metrics.CounterService;
import org.springframework.boot.actuate.metrics.GaugeService;
import org.springframework.stereotype.Component;

import static java.lang.String.format;
import static java.lang.System.currentTimeMillis;

@Slf4j
@Aspect
@Component
public class CustomMetricsCollector {

    private static final String COUNTER_TEMPLATE = "counter.%s.%s";
    private static final String GAUGE_TEMPLATE = "gauge.%s.%s";
    @Autowired
    private CounterService counterService;
    @Autowired
    private GaugeService gaugeService;

    @Around("@annotation(com.fxclub.metrics.CollectMetrics)")
    public Object collectMetrics(ProceedingJoinPoint pjp) throws Throwable {
        String typeName = pjp.getSignature().getDeclaringTypeName();
        String methodName = pjp.getSignature().getName();

        counterService.increment(format(COUNTER_TEMPLATE, typeName, methodName));

        long startTime = currentTimeMillis();
        try {
            return pjp.proceed();
        } finally {
            long elapsedTime = currentTimeMillis() - startTime;
            gaugeService.submit(format(GAUGE_TEMPLATE, typeName, methodName), elapsedTime);
        }
    }
}