1 files changed, 62 insertions, 0 deletions
diff --git a/internal/cpu/stresser.go b/internal/cpu/stresser.go
new file mode 100644
index 0000000..906467a
--- /dev/null
+++ b/internal/cpu/stresser.go
@@ -0,0 +1,62 @@
+// Package cpu provides CPU stress testing with multiple algorithms and chaos modes.
+package cpu
+
+import (
+	"context"
+	"math/rand"
+	"sync"
+	"time"
+)
+
+// stresser.go contains the main Stresser type, constructor, and lifecycle methods.
+
+// Stresser uses pointer receivers because it contains a sync.Mutex
+// and shared mutable state that must not be copied.
+type Stresser struct {
+	config  Config
+	cancel  context.CancelFunc
+	wg      sync.WaitGroup
+	mu      sync.Mutex
+	current Mode
+	rand    *rand.Rand
+}
+
+func New(cfg Config) *Stresser {
+	if cfg.Workers <= 0 {
+		cfg.Workers = 1
+	}
+	if cfg.IntensityMin <= 0 {
+		cfg.IntensityMin = 100
+	}
+	if cfg.IntensityMax <= 0 {
+		cfg.IntensityMax = 1000
+	}
+	if cfg.Mode == "" {
+		cfg.Mode = ModePrime
+	}
+	return &Stresser{
+		config: cfg,
+		rand:   rand.New(rand.NewSource(time.Now().UnixNano())),
+	}
+}
+
+func (s *Stresser) Start() {
+	ctx, cancel := context.WithCancel(context.Background())
+	s.cancel = cancel
+
+	s.wg.Add(s.config.Workers)
+	for i := 0; i < s.config.Workers; i++ {
+		go s.worker(ctx, i)
+	}
+
+	if s.config.ChaosEnabled {
+		go s.chaosController(ctx)
+	}
+}
+
+func (s *Stresser) Stop() {
+	if s.cancel != nil {
+		s.cancel()
+	}
+	s.wg.Wait()
+}