// SPDX-Licence-Identifier: EUPL-1.2

package html

import (
	"testing"

	i18n "dappco.re/go/core/i18n"
	"github.com/stretchr/testify/require"
)

type localeTranslator struct {
	language string
}

func (t *localeTranslator) T(key string, args ...any) string {
	if key == "prompt.yes" && t.language == "fr" {
		return "o"
	}
	if key == "prompt.yes" && t.language == "en" {
		return "y"
	}
	return key
}

func (t *localeTranslator) SetLanguage(language string) error {
	t.language = language
	return nil
}

func TestContext_NewContextWithService_AppliesLocale(t *testing.T) {
	svc := &localeTranslator{}
	ctx := NewContextWithService(svc, "fr-FR")

	if svc.language != "fr" {
		t.Fatalf("NewContextWithService should apply locale to translator, got %q", svc.language)
	}

	if got := Text("prompt.yes").Render(ctx); got != "o" {
		t.Fatalf("NewContextWithService locale translation = %q, want %q", got, "o")
	}
}

func TestContext_NewContext_AppliesLocaleToDefaultService(t *testing.T) {
	ctx := NewContext("fr-FR")

	if got := Text("prompt.yes").Render(ctx); got != "o" {
		t.Fatalf("NewContext(locale) translation = %q, want %q", got, "o")
	}
}

func TestContext_NewContextWithService_UsesLocale(t *testing.T) {
	svc := &localeTranslator{}
	ctx := NewContextWithService(svc, "en-GB")

	if svc.language != "en" {
		t.Fatalf("NewContextWithService should apply locale to translator, got %q", svc.language)
	}

	if got := Text("prompt.yes").Render(ctx); got != "y" {
		t.Fatalf("NewContextWithService translation = %q, want %q", got, "y")
	}
}

func TestContext_SetLocale_ReappliesToTranslator(t *testing.T) {
	svc := &localeTranslator{}
	ctx := NewContextWithService(svc, "en-GB")

	ctx.SetLocale("fr-FR")

	if ctx.Locale != "fr-FR" {
		t.Fatalf("SetLocale should update context locale, got %q", ctx.Locale)
	}
	if svc.language != "fr" {
		t.Fatalf("SetLocale should reapply locale to translator, got %q", svc.language)
	}
	if got := Text("prompt.yes").Render(ctx); got != "o" {
		t.Fatalf("SetLocale translation = %q, want %q", got, "o")
	}
}

func TestContext_SetService_ReappliesCurrentLocale(t *testing.T) {
	ctx := NewContext("fr-FR")
	svc := &localeTranslator{}

	ctx.SetService(svc)

	if ctx.service != svc {
		t.Fatalf("SetService should replace the active translator")
	}
	if svc.language != "fr" {
		t.Fatalf("SetService should apply the existing locale to the new translator, got %q", svc.language)
	}
	if got := Text("prompt.yes").Render(ctx); got != "o" {
		t.Fatalf("SetService translation = %q, want %q", got, "o")
	}
}

func TestContext_SetIdentity_UpdatesIdentity(t *testing.T) {
	ctx := NewContext()

	if got := ctx.SetIdentity("user-123"); got != ctx {
		t.Fatalf("SetIdentity should return the same context")
	}
	if ctx.Identity != "user-123" {
		t.Fatalf("SetIdentity should update context identity, got %q", ctx.Identity)
	}
	if ctx.Data == nil {
		t.Fatal("SetIdentity should preserve initialised Data map")
	}
}

func TestContext_Setters_NilReceiver(t *testing.T) {
	var ctx *Context

	if got := ctx.SetIdentity("user-123"); got != nil {
		t.Fatalf("nil Context.SetIdentity should return nil, got %v", got)
	}
	if got := ctx.SetLocale("en-GB"); got != nil {
		t.Fatalf("nil Context.SetLocale should return nil, got %v", got)
	}
	if got := ctx.SetService(&localeTranslator{}); got != nil {
		t.Fatalf("nil Context.SetService should return nil, got %v", got)
	}
}

func TestText_RenderFallsBackToDefaultTranslator(t *testing.T) {
	svc, _ := i18n.New()
	i18n.SetDefault(svc)
	require.NoError(t, svc.SetLanguage("fr"))

	ctx := &Context{}

	if got := Text("prompt.yes").Render(ctx); got != "o" {
		t.Fatalf("Text() fallback translation = %q, want %q", got, "o")
	}
}