package metrics

import (
	"gitea.pena/PenaDevops/smtpbiz-exporter/internal/worker/research"
	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promhttp"
	"net/http"
)

type Prometheus struct {
	research *research.Research
	metrics  prometheusRegistry
}

type prometheusRegistry struct {
	// Метрики отправленных писем и лимитов
	hourlyEmailsSent prometheus.Gauge // Количество писем, отправленных за последний час
	hourlyEmailLimit prometheus.Gauge // Лимит на количество писем, которые можно отправить за час
	dailyEmailsSent  prometheus.Gauge // Количество писем, отправленных за текущий день
	dailyEmailLimit  prometheus.Gauge // Лимит на количество писем, которые можно отправить за день

	// Метрики квот и баланса
	remainingQuota       prometheus.Gauge // Оставшееся количество писем, которые можно отправить в рамках текущего тарифа
	emailValidationLimit prometheus.Gauge // Лимит на количество проверок наверное емейл адресов
	tariffQuota          prometheus.Gauge // Общая квота на отправку писем, предоставляемая по тарифу
	balance              prometheus.Gauge // Баланс
}

func NewPrometheus(research *research.Research) *Prometheus {
	registry := prometheusRegistry{
		hourlyEmailsSent: prometheus.NewGauge(prometheus.GaugeOpts{
			Name: "hourly_emails_sent",
			Help: "Number of emails sent in the last hour",
		}),
		hourlyEmailLimit: prometheus.NewGauge(prometheus.GaugeOpts{
			Name: "hourly_email_limit",
			Help: "Limit on the number of emails that can be sent per hour",
		}),
		dailyEmailsSent: prometheus.NewGauge(prometheus.GaugeOpts{
			Name: "daily_emails_sent",
			Help: "Number of emails sent this day",
		}),
		dailyEmailLimit: prometheus.NewGauge(prometheus.GaugeOpts{
			Name: "daily_email_limit",
			Help: "Limit on the number of emails that can be sent per day",
		}),
		remainingQuota: prometheus.NewGauge(prometheus.GaugeOpts{
			Name: "remaining_quota",
			Help: "Remaining number of letters that can be sent within the current tariff",
		}),
		emailValidationLimit: prometheus.NewGauge(prometheus.GaugeOpts{
			Name: "email_validation_limit",
			Help: "The limit on the number of checks is probably email addresses",
		}),
		tariffQuota: prometheus.NewGauge(prometheus.GaugeOpts{
			Name: "tariff_quota",
			Help: "General quota for sending letters provided according to the tariff",
		}),
		balance: prometheus.NewGauge(prometheus.GaugeOpts{
			Name: "balance",
			Help: "Balance",
		}),
	}

	prometheus.MustRegister(
		registry.hourlyEmailsSent,
		registry.hourlyEmailLimit,
		registry.dailyEmailsSent,
		registry.dailyEmailLimit,
		registry.remainingQuota,
		registry.emailValidationLimit,
		registry.tariffQuota,
		registry.balance,
	)

	return &Prometheus{
		research: research,
		metrics:  registry,
	}
}

func (receiver *Prometheus) Metrics(w http.ResponseWriter, r *http.Request) {
	receiver.updateMetrics()
	handler := promhttp.Handler()

	handler.ServeHTTP(w, r)
}

func (receiver *Prometheus) updateMetrics() {
	receiver.metrics.hourlyEmailsSent.Set(float64(receiver.research.Metrics.HourlyEmailsSent))
	receiver.metrics.hourlyEmailLimit.Set(float64(receiver.research.Metrics.HourlyEmailLimit))
	receiver.metrics.dailyEmailsSent.Set(float64(receiver.research.Metrics.DailyEmailsSent))
	receiver.metrics.dailyEmailLimit.Set(float64(receiver.research.Metrics.DailyEmailLimit))
	receiver.metrics.remainingQuota.Set(float64(receiver.research.Metrics.RemainingQuota))
	receiver.metrics.emailValidationLimit.Set(float64(receiver.research.Metrics.EmailValidationLimit))
	receiver.metrics.tariffQuota.Set(float64(receiver.research.Metrics.TariffQuota))
	receiver.metrics.balance.Set(float64(receiver.research.Metrics.Balance))
}