package appconfig

import (
	"os"
	"path/filepath"
	"strings"
	"testing"

	"github.com/carlosframework/platform/internal/registry"
)

// A re-render never touches the instance's own env file, so the key minted
// there survives every config change, including one that sets the same
// name in the app's configuration (L21, never overwrite: re-render).
func TestSyncExecLeavesTheInstanceKeyAlone(t *testing.T) {
	ctx, s, reg, dd, priv, _ := execKit(t)
	pk, err := ParsePrivateKey(priv, "test")
	if err != nil {
		t.Fatal(err)
	}
	own := filepath.Join(dd, "shop.example.com.env")
	body := []byte("CARLOS_ADMIN_TOKEN=tok\nCARLOS_INSTANCE_KEY=q+/Zk3vJ0aW1Yx9sR7tUe2oPl4mN8bC6dF5gH0iJ1kA=\n")
	if err := os.WriteFile(own, body, 0o600); err != nil {
		t.Fatal(err)
	}
	rt := registry.Route{Host: "shop.example.com", Kind: "instance", App: "shop", Account: "acct", Status: "ready", Socket: "/run/carlos/shop.sock"}
	if err := reg.Upsert(rt); err != nil {
		t.Fatal(err)
	}
	for _, vars := range []map[string]string{{"A": "1"}, {"A": "2", "CARLOS_INSTANCE_KEY": "from-config"}} {
		if err := SetEnv(ctx, s, "acct", "shop", vars); err != nil {
			t.Fatal(err)
		}
		if err := SyncExec(ctx, reg, s, pk, dd, func(string) error { return nil }, "", nil); err != nil {
			t.Fatal(err)
		}
		// The render happened: <host>.config.env carries this pass's
		// variables, the configured key included. Without this the test
		// would pass against a SyncExec that skipped the route.
		rendered, err := os.ReadFile(ConfigEnvPath(dd, rt))
		if err != nil {
			t.Fatalf("no rendered configuration after SyncExec: %v", err)
		}
		got := map[string]string{}
		for _, line := range strings.Split(string(rendered), "\n") {
			if k, v, ok := strings.Cut(line, "="); ok {
				got[k] = v
			}
		}
		for k, v := range vars {
			if got[k] != v {
				t.Fatalf("rendered configuration lacks %s=%s (%d bytes, %d variables)", k, v, len(rendered), len(got))
			}
		}
		after, err := os.ReadFile(own)
		if err != nil {
			t.Fatalf("own env file after the render: %v", err)
		}
		if string(after) != string(body) {
			t.Fatalf("a re-render changed the instance's own env file: %d bytes, want %d", len(after), len(body))
		}
	}
}