package unsubscribe

import "testing"

func TestDetectListUnsubscribeHeader(t *testing.T) {
	res := Detect(
		"<mailto:unsub@heritagefruittrees.com.au?subject=unsubscribe>, <https://heritagefruittrees.com.au/u?id=42>",
		"List-Unsubscribe=One-Click",
		"Heritage Fruit Trees <support@heritagefruittrees.com.au>",
		"Special offer this week.",
	)
	if !res.OneClick {
		t.Error("OneClick = false, want true")
	}
	if len(res.Links) != 2 {
		t.Fatalf("Links len = %d, want 2 (%+v)", len(res.Links), res.Links)
	}
	mail := res.Links[0]
	if mail.Method != MethodMailto {
		t.Errorf("mailto method = %q", mail.Method)
	}
	if mail.Domain != "heritagefruittrees.com.au" {
		t.Errorf("mailto domain = %q", mail.Domain)
	}
	if mail.Source != SourceListUnsubscribe {
		t.Errorf("mailto source = %q", mail.Source)
	}
	http := res.Links[1]
	if http.Method != MethodHTTP {
		t.Errorf("http method = %q", http.Method)
	}
	if http.Host != "heritagefruittrees.com.au" {
		t.Errorf("http host = %q", http.Host)
	}
	if http.Domain != "heritagefruittrees.com.au" {
		t.Errorf("http domain = %q", http.Domain)
	}
}

func TestDetectBareHeaderURL(t *testing.T) {
	res := Detect("https://lists.example.com/unsub?u=abc,", "", "News <news@lists.example.com>", "")
	if len(res.Links) != 1 {
		t.Fatalf("Links = %+v, want 1", res.Links)
	}
	if res.Links[0].URL != "https://lists.example.com/unsub?u=abc" {
		t.Errorf("URL = %q", res.Links[0].URL)
	}
}

func TestDetectBodyFallback(t *testing.T) {
	res := Detect("", "", "Shop <deals@shop.example>", "Thanks for subscribing!\nUnsubscribe here: https://shop.example/opt-out?token=1.\nSee you.")
	if res.Header != "" {
		t.Errorf("Header = %q, want empty", res.Header)
	}
	if len(res.Links) != 1 {
		t.Fatalf("Links = %+v, want 1", res.Links)
	}
	if res.Links[0].Source != SourceBody {
		t.Errorf("Source = %q, want %q", res.Links[0].Source, SourceBody)
	}
	if res.Links[0].URL != "https://shop.example/opt-out?token=1" {
		t.Errorf("URL = %q (trailing period should be trimmed)", res.Links[0].URL)
	}
}

func TestDetectIgnoresUnrelatedBodyLinks(t *testing.T) {
	res := Detect("", "", "Friend <friend@example.com>", "Read more at https://example.com/blog")
	if len(res.Links) != 0 {
		t.Fatalf("Links = %+v, want none", res.Links)
	}
}

func TestDetectBodyMailto(t *testing.T) {
	res := Detect("", "", "Brand <hello@brand.example>", "To unsubscribe, email mailto:leave@brand.example")
	if len(res.Links) != 1 || res.Links[0].Method != MethodMailto {
		t.Fatalf("Links = %+v, want one mailto", res.Links)
	}
}

func TestFreeMailSenderUsesLinkHost(t *testing.T) {
	res := Detect(
		"<https://mailer.example.com/u/9>",
		"",
		"Someone <someone@gmail.com>",
		"",
	)
	if len(res.Links) != 1 {
		t.Fatalf("Links = %+v, want 1", res.Links)
	}
	if res.Links[0].Domain != "mailer.example.com" {
		t.Errorf("domain = %q, want link host", res.Links[0].Domain)
	}
}

func TestDetectDeduplicates(t *testing.T) {
	res := Detect(
		"<https://x.example/u>, <https://x.example/u>",
		"",
		"Brand <hello@brand.example>",
		"",
	)
	if len(res.Links) != 1 {
		t.Fatalf("Links = %+v, want 1 after de-duplication", res.Links)
	}
}

func TestDomain(t *testing.T) {
	cases := map[string]string{
		"Support <support@heritagefruittrees.com.au>": "heritagefruittrees.com.au",
		"plain@brand.example":                         "brand.example",
		"Someone <someone@gmail.com>":                 "",
		"":                                            "",
	}
	for in, want := range cases {
		if got := Domain(in); got != want {
			t.Errorf("Domain(%q) = %q, want %q", in, got, want)
		}
	}
}

func TestEmptyInputs(t *testing.T) {
	res := Detect("", "", "", "")
	if len(res.Links) != 0 || res.OneClick {
		t.Fatalf("Detect(empty) = %+v, want zero value", res)
	}
}