package richtext

import (
	"strings"
	"testing"
)

func TestToHTML_Markers(t *testing.T) {
	cases := []struct{ in, want string }{
		{"*bold*", "<strong>bold</strong>"},
		{"_italic_", "<em>italic</em>"},
		{"__under__", "<u>under</u>"},
		{"~gone~", "<s>gone</s>"},
		{"a *b* and _c_", "a <strong>b</strong> and <em>c</em>"},
		{"line one\nline two", "line one<br>line two"},
		// Underscores inside words are not italics.
		{"snake_case_name", "snake_case_name"},
		{"@some_handle here", "@some_handle here"},
	}
	for _, c := range cases {
		if got := string(ToHTML(c.in)); got != c.want {
			t.Errorf("ToHTML(%q) = %q, want %q", c.in, got, c.want)
		}
	}
}

func TestToHTML_Links(t *testing.T) {
	got := string(ToHTML("see [the gītā](https://prabhupadasays.org/books/bg)"))
	if !strings.Contains(got, `href="https://prabhupadasays.org/books/bg"`) ||
		!strings.Contains(got, ">the gītā</a>") {
		t.Errorf("labelled link: %q", got)
	}

	// A bare URL becomes a link, but sentence punctuation stays outside it.
	got = string(ToHTML("Visit https://prabhupadasays.org."))
	if !strings.Contains(got, `href="https://prabhupadasays.org"`) ||
		!strings.HasSuffix(got, "</a>.") {
		t.Errorf("bare link with trailing period: %q", got)
	}

	// Underscores and tildes inside a URL are not formatting.
	got = string(ToHTML("https://example.com/a_b_c~d"))
	if strings.Contains(got, "<em>") || strings.Contains(got, "<s>") {
		t.Errorf("markers applied inside a URL: %q", got)
	}
}

// The security property: nothing typed can become markup of its own.
func TestToHTML_EscapesAuthorInput(t *testing.T) {
	cases := []string{
		`<script>alert(1)</script>`,
		`<img src=x onerror=alert(1)>`,
		`*<b>bold</b>*`,
		`[click](javascript:alert(1))`,
		`[x](https://ok.example/" onmouseover="alert(1))`,
	}
	for _, in := range cases {
		got := string(ToHTML(in))
		if strings.Contains(got, "<script") || strings.Contains(got, "<img") ||
			strings.Contains(got, "<b>") || strings.Contains(got, "javascript:alert") && strings.Contains(got, "href=\"javascript") {
			t.Errorf("ToHTML(%q) produced author markup: %q", in, got)
		}
		if strings.Contains(got, `" onmouseover=`) {
			t.Errorf("ToHTML(%q) let a quote break out of an attribute: %q", in, got)
		}
	}
	// A javascript: URL is never made a link at all.
	if got := string(ToHTML(`[click](javascript:alert(1))`)); strings.Contains(got, "<a ") {
		t.Errorf("javascript: URL was linked: %q", got)
	}
}

func TestPlain(t *testing.T) {
	cases := []struct{ in, want string }{
		{"*New:* _chat_ is __here__ ~soon~", "New: chat is here soon"},
		{"read [the gītā](https://x.example)", "read the gītā"},
		{"see https://prabhupadasays.org", "see https://prabhupadasays.org"},
		{"snake_case stays", "snake_case stays"},
	}
	for _, c := range cases {
		if got := Plain(c.in); got != c.want {
			t.Errorf("Plain(%q) = %q, want %q", c.in, got, c.want)
		}
	}
}