package filex

import (
	"bytes"
	"os"
	"path/filepath"
	"testing"
)

func TestFillWithRandomAndCryptoRandom(t *testing.T) {
	dir := t.TempDir()
	pseudoPath := filepath.Join(dir, "pseudo.bin")
	securePath := filepath.Join(dir, "secure.bin")

	if err := FillWithRandom(pseudoPath, 2048, 128, 4, nil); err != nil {
		t.Fatalf("FillWithRandom failed: %v", err)
	}
	if err := FillWithCryptoRandom(securePath, 2048, 128, nil); err != nil {
		t.Fatalf("FillWithCryptoRandom failed: %v", err)
	}

	pseudoInfo, err := os.Stat(pseudoPath)
	if err != nil {
		t.Fatalf("stat pseudo file failed: %v", err)
	}
	if pseudoInfo.Size() != 2048 {
		t.Fatalf("unexpected pseudo size: %d", pseudoInfo.Size())
	}

	secureInfo, err := os.Stat(securePath)
	if err != nil {
		t.Fatalf("stat secure file failed: %v", err)
	}
	if secureInfo.Size() != 2048 {
		t.Fatalf("unexpected secure size: %d", secureInfo.Size())
	}

	pseudo, err := os.ReadFile(pseudoPath)
	if err != nil {
		t.Fatalf("read pseudo file failed: %v", err)
	}
	secure, err := os.ReadFile(securePath)
	if err != nil {
		t.Fatalf("read secure file failed: %v", err)
	}

	if bytes.Equal(secure, make([]byte, len(secure))) {
		t.Fatalf("secure random output should not be all zero")
	}
	if bytes.Equal(pseudo, secure) {
		t.Fatalf("pseudo and secure random outputs unexpectedly identical")
	}
}

func TestFillWithRandomInvalidArgs(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "bad.bin")

	if err := FillWithRandom(path, -1, 16, 1, nil); err == nil {
		t.Fatalf("expected FillWithRandom negative filesize error")
	}
	if err := FillWithCryptoRandom(path, -1, 16, nil); err == nil {
		t.Fatalf("expected FillWithCryptoRandom negative filesize error")
	}
}