package metrics

import (
	"context"
	"database/sql"
)

// SampleStoreGauges 按库内真实计数刷新端总数、待投递、定时消息（无对应行则为 0）。
func SampleStoreGauges(ctx context.Context, r *Registry, db *sql.DB) error {
	if r == nil || db == nil {
		return nil
	}
	var endpoints, pending, scheduled int
	if err := db.QueryRowContext(ctx, `SELECT COUNT(*) FROM endpoints`).Scan(&endpoints); err != nil {
		return err
	}
	if err := db.QueryRowContext(ctx, `SELECT COUNT(*) FROM deliveries WHERE state = 'pending'`).Scan(&pending); err != nil {
		return err
	}
	if err := db.QueryRowContext(ctx, `SELECT COUNT(*) FROM messages WHERE state = 'scheduled'`).Scan(&scheduled); err != nil {
		return err
	}
	r.EndpointsTotal.Set(float64(endpoints))
	r.DeliveriesPending.Set(float64(pending))
	r.MessagesScheduled.Set(float64(scheduled))
	return nil
}

// SampleQueues 刷新写队列与密码哈希排队长度（传入当前真实长度，不做估算）。
func SampleQueues(r *Registry, writeQueueLen, passwordHashQueueLen int) {
	if r == nil {
		return
	}
	r.WriteQueueLength.Set(float64(writeQueueLen))
	r.PasswordHashQueue.Set(float64(passwordHashQueueLen))
}