package main

import (
	"os"
	"path/filepath"
	"testing"
)

func TestCheckHTMLSanitize_RegexStrip(t *testing.T) {
	dir := t.TempDir()
	writeFile(t, dir, "bad.go", `package foo

import "regexp"

func clean(s string) string {
	re := regexp.MustCompile(`+"`"+`<[^>]*>`+"`"+`)
	return re.ReplaceAllString(s, "")
}
`)
	vs := checkHTMLSanitize(dir)
	if len(vs) == 0 {
		t.Fatal("expected regex-html-strip violation")
	}
	if vs[0].rule != "regex-html-strip" {
		t.Fatalf("expected rule regex-html-strip, got %s", vs[0].rule)
	}
}

func TestCheckHTMLSanitize_ScriptRegex(t *testing.T) {
	dir := t.TempDir()
	writeFile(t, dir, "bad.go", `package foo

import "regexp"

func clean(s string) string {
	re := regexp.MustCompile(`+"`"+`(?s)<script[^>]*>.*?</script>`+"`"+`)
	return re.ReplaceAllString(s, "")
}
`)
	vs := checkHTMLSanitize(dir)
	if len(vs) == 0 {
		t.Fatal("expected regex-html-strip violation for <script>")
	}
}

func TestCheckHTMLSanitize_HandRolledFunc(t *testing.T) {
	dir := t.TempDir()
	writeFile(t, dir, "bad.go", `package foo

func stripHTML(s string) string {
	return s
}
`)
	vs := checkHTMLSanitize(dir)
	if len(vs) == 0 {
		t.Fatal("expected hand-rolled-strip-func violation")
	}
	if vs[0].rule != "hand-rolled-strip-func" {
		t.Fatalf("expected rule hand-rolled-strip-func, got %s", vs[0].rule)
	}
}

func TestCheckHTMLSanitize_CharByChar(t *testing.T) {
	dir := t.TempDir()
	writeFile(t, dir, "bad.go", `package foo

func strip(s string) string {
	inTag := false
	for _, r := range s {
		if r == '<' {
			inTag = true
		}
	}
	_ = inTag
	return s
}
`)
	vs := checkHTMLSanitize(dir)
	if len(vs) == 0 {
		t.Fatal("expected char-by-char-tag-strip violation")
	}
}

func TestCheckHTMLSanitize_BluemondayOK(t *testing.T) {
	dir := t.TempDir()
	writeFile(t, dir, "good.go", `package foo

import "github.com/microcosm-cc/bluemonday"

func clean(s string) string {
	return bluemonday.StrictPolicy().Sanitize(s)
}
`)
	vs := checkHTMLSanitize(dir)
	if len(vs) != 0 {
		t.Fatalf("expected no violations for bluemonday usage, got %d", len(vs))
	}
}

func TestCheckHTMLSanitize_TestFilesAllowed(t *testing.T) {
	dir := t.TempDir()
	writeFile(t, dir, "strip_test.go", `package foo

func stripHTML(s string) string {
	return s
}
`)
	vs := checkHTMLSanitize(dir)
	if len(vs) != 0 {
		t.Fatalf("expected test files to be allowed, got %d violations", len(vs))
	}
}

func writeFile(t *testing.T, dir, name, content string) {
	t.Helper()
	err := os.WriteFile(filepath.Join(dir, name), []byte(content), 0o644)
	if err != nil {
		t.Fatal(err)
	}
}