feat: observer pattern for statistics

internal/statistics/results.go

@@ -0,0 +1,23 @@
+package statistics
+
+import (
+	"fmt"
+	"strings"
+)
+
+type Results struct {
+	StepsTaken  uint64 // Number of steps taken during execution.
+	TimeElapsed uint64 // The time (ms) taken for execution to complete.
+}
+
+func (r Results) OpsPerSecond() float32 {
+	return float32(r.StepsTaken) / (float32(r.TimeElapsed) / 1000)
+}
+
+func (r Results) String() string {
+	builder := strings.Builder{}
+	fmt.Fprintln(&builder, "Time Spent:", r.TimeElapsed, "ms")
+	fmt.Fprintln(&builder, "Steps:", r.StepsTaken)
+	fmt.Fprintln(&builder, "Speed:", r.OpsPerSecond(), "ops")
+	return builder.String()
+}

internal/statistics/statistics.go

@@ -0,0 +1,30 @@
+package statistics
+
+import (
+	"time"
+
+	"git.maximhutz.com/max/lambda/pkg/lambda"
+)
+
+type Profiler struct {
+	start   time.Time
+	steps   uint64
+	Results *Results
+}
+
+func (p *Profiler) Start(*lambda.Expression) {
+	p.start = time.Now()
+	p.steps = 0
+	p.Results = nil
+}
+
+func (p *Profiler) Step(*lambda.Expression) {
+	p.steps++
+}
+
+func (p *Profiler) End(*lambda.Expression) {
+	p.Results = &Results{
+		StepsTaken:  p.steps,
+		TimeElapsed: uint64(time.Since(p.start).Milliseconds()),
+	}
+}