package pdu

import (
	"sync"
	"testing"
)

func TestRetrieveBufferOfRequestedSize(t *testing.T) {
	bpm := &BufferPoolManager{
		pools: make(map[uint]*sync.Pool),
		mu:    sync.Mutex{},
	}

	size := 1024
	buffer := bpm.GetBuffer(uint(size))

	if buffer == nil {
		t.Fatalf("Expected buffer, got nil")
	}

	if len(*buffer) != size {
		t.Errorf("Expected buffer size %d, got %d", size, len(*buffer))
	}
}

func TestRequestBufferSizeZero(t *testing.T) {
	bpm := &BufferPoolManager{
		pools: make(map[uint]*sync.Pool),
		mu:    sync.Mutex{},
	}

	size := 0
	buffer := bpm.GetBuffer(uint(size))

	if buffer == nil {
		t.Fatalf("Expected buffer, got nil")
	}

	if len(*buffer) != size {
		t.Errorf("Expected buffer size %d, got %d", size, len(*buffer))
	}
}

func TestConcurrentAccessToBufferPool(t *testing.T) {
	bpm := &BufferPoolManager{
		pools: make(map[uint]*sync.Pool),
		mu:    sync.Mutex{},
	}

	size := 1024
	var wg sync.WaitGroup
	numRoutines := 100

	for i := 0; i < numRoutines; i++ {
		wg.Add(1)
		go func() {
			defer wg.Done()
			buffer := bpm.GetBuffer(uint(size))
			if buffer == nil {
				t.Errorf("Expected buffer, got nil")
			}
			if len(*buffer) != size {
				t.Errorf("Expected buffer size %d, got %d", size, len(*buffer))
			}
		}()
	}

	wg.Wait()
}

func TestGetBufferLockUnlock(t *testing.T) {
	bpm := &BufferPoolManager{
		pools: make(map[uint]*sync.Pool),
		mu:    sync.Mutex{},
	}

	size := 1024
	buffer := bpm.GetBuffer(uint(size))

	if buffer == nil {
		t.Fatalf("Expected buffer, got nil")
	}

	if len(*buffer) != size {
		t.Errorf("Expected buffer size %d, got %d", size, len(*buffer))
	}
}

func TestVerifyPoolCreationForNewSizes(t *testing.T) {
	bpm := &BufferPoolManager{
		pools: make(map[uint]*sync.Pool),
		mu:    sync.Mutex{},
	}

	size := 512
	buffer := bpm.GetBuffer(uint(size))

	if buffer == nil {
		t.Fatalf("Expected buffer, got nil")
	}

	if len(*buffer) != size {
		t.Errorf("Expected buffer size %d, got %d", size, len(*buffer))
	}
}

func TestBufferPoolManagerGetBuffer(t *testing.T) {
	bpm := &BufferPoolManager{
		pools: make(map[uint]*sync.Pool),
		mu:    sync.Mutex{},
	}

	size := 1024
	buffer := bpm.GetBuffer(uint(size))

	if buffer == nil {
		t.Fatalf("Expected buffer, got nil")
	}

	if len(*buffer) != size {
		t.Errorf("Expected buffer size %d, got %d", size, len(*buffer))
	}
}

func TestGetBufferWithMultipleSizes(t *testing.T) {
	bpm := &BufferPoolManager{
		pools: make(map[uint]*sync.Pool),
		mu:    sync.Mutex{},
	}

	sizes := []int{512, 1024, 2048}
	for _, size := range sizes {
		buffer := bpm.GetBuffer(uint(size))

		if buffer == nil {
			t.Fatalf("Expected buffer for size %d, got nil", size)
		}

		if len(*buffer) != size {
			t.Errorf("Expected buffer size %d, got %d", size, len(*buffer))
		}
	}
}