package sanitize

import (
	"strings"
	"testing"
)

func TestStripHiddenEmailHTML_removesMailchimpPreheaderPadding(t *testing.T) {
	const padding = "͏ \u200c \u00a0 \u2007 "
	in := `<div style="display: none; max-height: 0px; overflow: hidden;">` + strings.Repeat(padding, 20) + `</div>` +
		`<p>All motor files are now structured by model.</p>`
	out := StripHiddenEmailHTML(in)
	if strings.Contains(out, "\u034f") || strings.Contains(out, "\u200c") {
		t.Fatalf("invisible padding remains: %q", out)
	}
	if !strings.Contains(out, "All motor files") {
		t.Fatalf("visible content removed: %q", out)
	}
}

func TestSanitizeHTML_stripsHiddenPreheader(t *testing.T) {
	in := `<div style="display: none;">hidden junk</div><p>Hello world</p>`
	got := SanitizeHTML(in)
	if strings.Contains(got, "hidden junk") {
		t.Fatalf("hidden preheader leaked after sanitize: %q", got)
	}
	if !strings.Contains(got, "Hello world") {
		t.Fatalf("visible content missing: %q", got)
	}
}

func TestStripInvisibleTextRuns(t *testing.T) {
	in := "Hello " + strings.Repeat("\u034f\u200c\u00a0\u2007 ", 30) + "world"
	got := StripInvisibleTextRuns(in)
	if strings.Contains(got, "\u034f") {
		t.Fatalf("padding remains: %q", got)
	}
	if got != "Hello world" {
		t.Fatalf("got %q", got)
	}
}

func TestStripInvisibleTextRuns_preservesNewlines(t *testing.T) {
	in := "Reply line one\nOn 22/04/2026 wrote:\n> quoted"
	got := StripInvisibleTextRuns(in)
	if !strings.Contains(got, "\n") {
		t.Fatalf("newlines collapsed: %q", got)
	}
	if !strings.Contains(got, "> quoted") {
		t.Fatalf("quote line missing: %q", got)
	}
}