package cmd

import (
	"path/filepath"
	"testing"
	"time"
)

func TestReadWriteRoundtrip(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "test.ndjson")

	entries := []Entry{
		{Key: "alpha", Value: []byte("hello")},
		{Key: "beta", Value: []byte("world"), ExpiresAt: uint64(time.Now().Add(time.Hour).Unix())},
		{Key: "gamma", Value: []byte{0xff, 0xfe}}, // binary
	}

	if err := writeStoreFile(path, entries); err != nil {
		t.Fatal(err)
	}

	got, err := readStoreFile(path)
	if err != nil {
		t.Fatal(err)
	}

	if len(got) != len(entries) {
		t.Fatalf("got %d entries, want %d", len(got), len(entries))
	}
	for i := range entries {
		if got[i].Key != entries[i].Key {
			t.Errorf("entry %d: key = %q, want %q", i, got[i].Key, entries[i].Key)
		}
		if string(got[i].Value) != string(entries[i].Value) {
			t.Errorf("entry %d: value mismatch", i)
		}
	}
}

func TestReadStoreFileSkipsExpired(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "test.ndjson")

	entries := []Entry{
		{Key: "alive", Value: []byte("yes")},
		{Key: "dead", Value: []byte("no"), ExpiresAt: 1}, // expired long ago
	}

	if err := writeStoreFile(path, entries); err != nil {
		t.Fatal(err)
	}

	got, err := readStoreFile(path)
	if err != nil {
		t.Fatal(err)
	}

	if len(got) != 1 || got[0].Key != "alive" {
		t.Fatalf("expected only 'alive', got %v", got)
	}
}

func TestReadStoreFileNotExist(t *testing.T) {
	got, err := readStoreFile("/nonexistent/path.ndjson")
	if err != nil {
		t.Fatal(err)
	}
	if len(got) != 0 {
		t.Fatalf("expected empty, got %d entries", len(got))
	}
}

func TestWriteStoreFileSortsKeys(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "test.ndjson")

	entries := []Entry{
		{Key: "charlie", Value: []byte("3")},
		{Key: "alpha", Value: []byte("1")},
		{Key: "bravo", Value: []byte("2")},
	}

	if err := writeStoreFile(path, entries); err != nil {
		t.Fatal(err)
	}

	got, err := readStoreFile(path)
	if err != nil {
		t.Fatal(err)
	}

	if got[0].Key != "alpha" || got[1].Key != "bravo" || got[2].Key != "charlie" {
		t.Fatalf("entries not sorted: %v", got)
	}
}

func TestWriteStoreFileAtomic(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "test.ndjson")

	// Write initial data
	if err := writeStoreFile(path, []Entry{{Key: "a", Value: []byte("1")}}); err != nil {
		t.Fatal(err)
	}

	// Overwrite — should not leave .tmp files
	if err := writeStoreFile(path, []Entry{{Key: "b", Value: []byte("2")}}); err != nil {
		t.Fatal(err)
	}

	// Check no .tmp file remains
	matches, _ := filepath.Glob(filepath.Join(dir, "*.tmp"))
	if len(matches) > 0 {
		t.Fatalf("leftover tmp files: %v", matches)
	}
}