package lang

import (
	"strings"
	"testing"
)

func TestGenerateGoDataClassUsesSnakeCaseJSONTags(t *testing.T) {
	prog, err := Parse(`
package demo

data class KeycloakToken(var accessToken: String, var refreshToken: String)
`)
	if err != nil {
		t.Fatalf("parse failed: %v", err)
	}
	out, err := GenerateGo(prog)
	if err != nil {
		t.Fatalf("generation failed: %v", err)
	}
	for _, want := range []string{"AccessToken", "`json:\"access_token\"`", "RefreshToken", "`json:\"refresh_token\"`"} {
		if !strings.Contains(string(out), want) {
			t.Fatalf("generated Go missing %q:\n%s", want, out)
		}
	}
}

func TestGenerateGoDataClassJSONNamingOverride(t *testing.T) {
	prog, err := Parse(`
package demo

@jsonNaming(camelCase)
data class Account(var availableBalance: Double)
`)
	if err != nil {
		t.Fatalf("parse failed: %v", err)
	}
	out, err := GenerateGo(prog)
	if err != nil {
		t.Fatalf("generation failed: %v", err)
	}
	if !strings.Contains(string(out), "`json:\"availableBalance\"`") {
		t.Fatalf("generated Go missing camelCase tag:\n%s", out)
	}
}

func TestGenerateGoDataClassFieldVisibilityAndSelector(t *testing.T) {
	prog, err := Parse(`
package demo

import json encoding.json

data class Request(var email: String, private val traceId: String)

fun email(body: ByteSlice): String {
    val request = json.decode<Request>(body)
    return request.email
}
`)
	if err != nil {
		t.Fatalf("parse failed: %v", err)
	}
	out, err := GenerateGo(prog)
	if err != nil {
		t.Fatalf("generation failed: %v", err)
	}
	for _, want := range []string{"Email", "`json:\"email\"`", "traceId string `json:\"-\"`", "return request.Email"} {
		if !strings.Contains(string(out), want) {
			t.Fatalf("generated Go missing %q:\n%s", want, out)
		}
	}
}