//go:build withsidecar

package sidecarassets

import (
	"bytes"
	"crypto/sha256"
	"encoding/hex"
	"os"
	"path/filepath"
	"testing"
)

func TestEmbeddedNonZero(t *testing.T) {
	if EmbeddedSize() == 0 {
		t.Errorf("expected embedded JAR to be non-empty")
	}
	if IsPlaceholder() {
		t.Errorf("withsidecar build should not be a placeholder")
	}
}

func TestExtract_WritesJARAndChecksum(t *testing.T) {
	directory := t.TempDir()
	path, err := Extract(directory)
	if err != nil {
		t.Fatal(err)
	}
	if path != filepath.Join(directory, "sanderling-sidecar.jar") {
		t.Errorf("unexpected path: %s", path)
	}
	body, err := os.ReadFile(path)
	if err != nil {
		t.Fatal(err)
	}
	if EmbeddedSize() != len(body) {
		t.Errorf("size mismatch: embedded=%d, written=%d", EmbeddedSize(), len(body))
	}
	sum := sha256.Sum256(body)
	if hex.EncodeToString(sum[:]) != EmbeddedSHA256() {
		t.Errorf("hash mismatch")
	}
	checksum, err := os.ReadFile(path + ".sha256")
	if err != nil {
		t.Fatal(err)
	}
	if string(checksum) != EmbeddedSHA256() {
		t.Errorf("checksum file content wrong: %q", checksum)
	}
}

func TestExtract_ReusesIdenticalFile(t *testing.T) {
	directory := t.TempDir()
	path, err := Extract(directory)
	if err != nil {
		t.Fatal(err)
	}
	sentinel := []byte("SENTINEL-do-not-rewrite")
	if err := os.WriteFile(path, sentinel, 0o644); err != nil {
		t.Fatal(err)
	}

	if _, err := Extract(directory); err != nil {
		t.Fatal(err)
	}

	after, err := os.ReadFile(path)
	if err != nil {
		t.Fatal(err)
	}
	if !bytes.Equal(after, sentinel) {
		t.Errorf("second extract rewrote the existing JAR; reuse branch corrupted on-disk file")
	}
}

func TestExtract_RewritesIfChecksumMissing(t *testing.T) {
	directory := t.TempDir()
	path, err := Extract(directory)
	if err != nil {
		t.Fatal(err)
	}
	if err := os.Remove(path + ".sha256"); err != nil {
		t.Fatal(err)
	}
	if _, err := Extract(directory); err != nil {
		t.Fatal(err)
	}
	if _, err := os.Stat(path + ".sha256"); err != nil {
		t.Errorf("checksum should have been written: %v", err)
	}
}