package server

import (
	"net/http"

	"github.com/JetBrains/ij-perf-report-aggregator/pkg/analyzer"
	"github.com/valyala/bytebufferpool"
	"github.com/valyala/quicktemplate"
)

func (t *StatsServer) handleMetaMeasureRequest(_ *http.Request) (*bytebufferpool.ByteBuffer, bool, error) {
	buffer := byteBufferPool.Get()
	isOk := false
	defer func() {
		if !isOk {
			byteBufferPool.Put(buffer)
		}
	}()

	measureNames := make([]string, len(analyzer.IjMetricDescriptors))
	for index, descriptor := range analyzer.IjMetricDescriptors {
		measureNames[index] = descriptor.Name
	}

	templateWriter := quicktemplate.AcquireWriter(buffer)
	defer quicktemplate.ReleaseWriter(templateWriter)
	jsonWriter := templateWriter.N()
	jsonWriter.S("[")
	for index, name := range measureNames {
		if index != 0 {
			jsonWriter.S(",")
		}
		jsonWriter.Q(name)
	}
	jsonWriter.S("]")

	isOk = true
	return buffer, true, nil
}