// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: MIT

package scriptorium

import (
	"bytes"
	"testing"
)

func TestSupportedDiagram(t *testing.T) {
	supported := []string{"flowchart", "graph", "sequenceDiagram"}
	for _, kind := range supported {
		if !SupportedDiagram(kind) {
			t.Errorf("SupportedDiagram(%q) = false, want true", kind)
		}
	}
	refused := []string{"", "stateDiagram-v2", "pie", "gantt", "classDiagram", "Flowchart"}
	for _, kind := range refused {
		if SupportedDiagram(kind) {
			t.Errorf("SupportedDiagram(%q) = true, want false", kind)
		}
	}
}

func TestRender(t *testing.T) {
	got := string(Render([]byte("# Title\n\nHello *world*.\n")))
	want := "<h1>Title</h1>\n<p>Hello <em>world</em>.</p>\n"
	if got != want {
		t.Errorf("Render = %q, want %q", got, want)
	}
}

func TestRenderDeterministic(t *testing.T) {
	source := []byte("- one\n- two\n\n```go\nfmt.Println(1)\n```\n")
	first := Render(source)
	for range 5 {
		if next := Render(source); !bytes.Equal(first, next) {
			t.Fatal("Render of the same source differs between calls")
		}
	}
}

func TestRenderMath(t *testing.T) {
	got := string(RenderMath([]byte(`\frac{1}{2}`)))
	want := `<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>1</mn><mn>2</mn></mfrac></math>`
	if got != want {
		t.Errorf("RenderMath = %s, want %s", got, want)
	}
}

func TestRenderMathDisplay(t *testing.T) {
	got := string(RenderMathDisplay([]byte("x")))
	want := `<math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><mi>x</mi></math>`
	if got != want {
		t.Errorf("RenderMathDisplay = %s, want %s", got, want)
	}
}

func TestRenderDiagram(t *testing.T) {
	out, err := RenderDiagram([]byte("flowchart TD\n  A[Start] --> B[End]\n"))
	if err != nil {
		t.Fatalf("render: %v", err)
	}
	if !bytes.HasPrefix(out, []byte(`<svg xmlns="http://www.w3.org/2000/svg"`)) {
		t.Errorf("RenderDiagram = %s", out)
	}
}

func TestRenderDiagramRefuses(t *testing.T) {
	if _, err := RenderDiagram([]byte("pie\n  \"a\": 1\n")); err == nil {
		t.Error("expected a refusal for an unsupported diagram type")
	}
}

func TestRenderDiagramDeterministic(t *testing.T) {
	source := []byte("sequenceDiagram\n  A->>B: hello\n  B-->>A: bye\n")
	first, err := RenderDiagram(source)
	if err != nil {
		t.Fatalf("render: %v", err)
	}
	for range 5 {
		next, err := RenderDiagram(source)
		if err != nil || !bytes.Equal(first, next) {
			t.Fatal("RenderDiagram of the same source differs between calls")
		}
	}
}