// SPDX-License-Identifier: AGPL-3.0-or-later

package render

import (
	"context"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"kode.naiv.no/olemd/favoritter/internal/config"
)

func testRenderer(t *testing.T) *Renderer {
	t.Helper()
	cfg := &config.Config{
		SiteName: "Test Site",
		BasePath: "/test",
	}
	r, err := New(cfg)
	if err != nil {
		t.Fatalf("create renderer: %v", err)
	}
	return r
}

func TestRenderPage(t *testing.T) {
	r := testRenderer(t)

	req := httptest.NewRequest("GET", "/", nil)
	rr := httptest.NewRecorder()

	r.Page(rr, req, "login", PageData{
		Title: "Logg inn",
	})

	if rr.Code != http.StatusOK {
		t.Errorf("render page: got %d, want 200", rr.Code)
	}

	body := rr.Body.String()
	if !strings.Contains(body, "Logg inn") {
		t.Error("page should contain title")
	}
	ct := rr.Header().Get("Content-Type")
	if !strings.Contains(ct, "text/html") {
		t.Errorf("content-type = %q, want text/html", ct)
	}
}

func TestRenderPageWithData(t *testing.T) {
	r := testRenderer(t)

	req := httptest.NewRequest("GET", "/", nil)
	rr := httptest.NewRecorder()

	r.Page(rr, req, "login", PageData{
		Title:    "Test Page",
		SiteName: "My Site",
		BasePath: "/base",
	})

	body := rr.Body.String()
	if !strings.Contains(body, "Test Page") {
		t.Error("should contain title in output")
	}
}

func TestRenderMissingTemplate(t *testing.T) {
	r := testRenderer(t)

	req := httptest.NewRequest("GET", "/", nil)
	rr := httptest.NewRecorder()

	r.Page(rr, req, "nonexistent_template_xyz", PageData{})

	if rr.Code != http.StatusInternalServerError {
		t.Errorf("missing template: got %d, want 500", rr.Code)
	}
}

func TestRenderErrorPage(t *testing.T) {
	r := testRenderer(t)

	req := httptest.NewRequest("GET", "/", nil)
	rr := httptest.NewRecorder()

	r.Error(rr, req, http.StatusNotFound, "Ikke funnet")

	if rr.Code != http.StatusNotFound {
		t.Errorf("error page: got %d, want 404", rr.Code)
	}
	body := rr.Body.String()
	if !strings.Contains(body, "Ikke funnet") {
		t.Error("error page should contain message")
	}
}

func TestRenderPopulatesCommonData(t *testing.T) {
	cfg := &config.Config{
		SiteName:    "Favoritter",
		BasePath:    "/app",
		ExternalURL: "https://example.com",
	}
	r, err := New(cfg)
	if err != nil {
		t.Fatalf("create renderer: %v", err)
	}

	req := httptest.NewRequest("GET", "/", nil)
	// Add a CSRF token to the context.
	type contextKey string
	ctx := context.WithValue(req.Context(), contextKey("csrf_token"), "test-token")
	req = req.WithContext(ctx)

	rr := httptest.NewRecorder()
	r.Page(rr, req, "login", PageData{Title: "Test"})

	// BasePath and SiteName should be populated from config.
	body := rr.Body.String()
	if !strings.Contains(body, "/app") {
		t.Error("should contain basePath from config")
	}
}

func TestTemplateFuncs(t *testing.T) {
	cfg := &config.Config{BasePath: "/test", ExternalURL: "https://example.com"}
	r, _ := New(cfg)

	funcs := r.templateFuncs()

	// Test truncate function.
	truncate := funcs["truncate"].(func(int, string) string)
	if got := truncate(5, "Hello, world!"); got != "Hello..." {
		t.Errorf("truncate(5, long) = %q, want Hello...", got)
	}
	if got := truncate(20, "Short"); got != "Short" {
		t.Errorf("truncate(20, short) = %q, want Short", got)
	}
	// Test with Norwegian characters (Ærlig = 5 runes: Æ r l i g).
	if got := truncate(3, "Ærlig"); got != "Ærl..." {
		t.Errorf("truncate(3, Ærlig) = %q, want Ærl...", got)
	}

	// Test add/subtract.
	add := funcs["add"].(func(int, int) int)
	if add(2, 3) != 5 {
		t.Error("add(2,3) should be 5")
	}
	sub := funcs["subtract"].(func(int, int) int)
	if sub(5, 3) != 2 {
		t.Error("subtract(5,3) should be 2")
	}

	// Test basePath function.
	bp := funcs["basePath"].(func() string)
	if bp() != "/test" {
		t.Errorf("basePath() = %q", bp())
	}
}