// vfs/memory/memory_test.go
package memory

import (
	"errors"
	"fmt"
	"io"
	"s1d3sw1ped/SteamCache2/vfs/vfserror"
	"testing"
)

func TestCreateAndOpen(t *testing.T) {
	m := New(1024)
	key := "key"
	value := []byte("value")

	w, err := m.Create(key, int64(len(value)))
	if err != nil {
		t.Fatalf("Create failed: %v", err)
	}
	w.Write(value)
	w.Close()

	rc, err := m.Open(key)
	if err != nil {
		t.Fatalf("Open failed: %v", err)
	}
	got, _ := io.ReadAll(rc)
	rc.Close()

	if string(got) != string(value) {
		t.Fatalf("expected %s, got %s", value, got)
	}
}

func TestOverwrite(t *testing.T) {
	m := New(1024)
	key := "key"
	value1 := []byte("value1")
	value2 := []byte("value2")

	w, err := m.Create(key, int64(len(value1)))
	if err != nil {
		t.Fatalf("Create failed: %v", err)
	}
	w.Write(value1)
	w.Close()

	w, err = m.Create(key, int64(len(value2)))
	if err != nil {
		t.Fatalf("Create failed: %v", err)
	}
	w.Write(value2)
	w.Close()

	rc, err := m.Open(key)
	if err != nil {
		t.Fatalf("Open failed: %v", err)
	}
	got, _ := io.ReadAll(rc)
	rc.Close()

	if string(got) != string(value2) {
		t.Fatalf("expected %s, got %s", value2, got)
	}
}

func TestDelete(t *testing.T) {
	m := New(1024)
	key := "key"
	value := []byte("value")

	w, err := m.Create(key, int64(len(value)))
	if err != nil {
		t.Fatalf("Create failed: %v", err)
	}
	w.Write(value)
	w.Close()

	if err := m.Delete(key); err != nil {
		t.Fatalf("Delete failed: %v", err)
	}

	_, err = m.Open(key)
	if !errors.Is(err, vfserror.ErrNotFound) {
		t.Fatalf("expected %v, got %v", vfserror.ErrNotFound, err)
	}
}

func TestCapacityLimit(t *testing.T) {
	m := New(10)
	for i := 0; i < 11; i++ {
		w, err := m.Create(fmt.Sprintf("key%d", i), 1)
		if err != nil && i < 10 {
			t.Errorf("Create failed: %v", err)
		} else if i == 10 && err == nil {
			t.Errorf("Create succeeded: got nil, want %v", vfserror.ErrDiskFull)
		}
		if i < 10 {
			w.Write([]byte("1"))
			w.Close()
		}
	}
}

func TestStat(t *testing.T) {
	m := New(1024)
	key := "key"
	value := []byte("value")

	w, err := m.Create(key, int64(len(value)))
	if err != nil {
		t.Fatalf("Create failed: %v", err)
	}
	w.Write(value)
	w.Close()

	info, err := m.Stat(key)
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}

	if info == nil {
		t.Fatal("expected file info to be non-nil")
	}
	if info.Size() != int64(len(value)) {
		t.Errorf("expected size %d, got %d", len(value), info.Size())
	}
}