package mail

import (
	"errors"
	"net/smtp"
	"strings"
	"testing"
)

func TestNewDynamicResolvesOnEachCall(t *testing.T) {
	calls := 0
	m := NewDynamic(func() (Config, error) {
		calls++
		return Config{
			Enabled: true,
			Host:    "smtp.example.com",
			Port:    "587",
			From:    "noreply@example.com",
		}, nil
	})
	if !m.Enabled() {
		t.Fatal("expected enabled")
	}
	if calls != 1 {
		t.Fatalf("calls=%d", calls)
	}

	prev := smtpSendMail
	smtpSendMail = func(addr string, auth smtp.Auth, from string, to []string, msg []byte) error {
		return nil
	}
	t.Cleanup(func() { smtpSendMail = prev })

	if err := m.Send(Message{To: "a@example.com", Subject: "hi", Text: "body"}); err != nil {
		t.Fatal(err)
	}
	if calls != 2 {
		t.Fatalf("expected second resolve on Send, calls=%d", calls)
	}
}

func TestNewDynamicDisabledIsNoop(t *testing.T) {
	m := NewDynamic(func() (Config, error) {
		return Config{Enabled: false}, nil
	})
	if m.Enabled() {
		t.Fatal("expected disabled")
	}
	if err := m.Send(Message{To: "a@b.c", Subject: "x", Text: "y"}); err != nil {
		t.Fatal(err)
	}
}

func TestRequireConfiguredErrorsWhenOff(t *testing.T) {
	m := RequireConfigured(NewDynamic(func() (Config, error) {
		return Config{}, nil
	}))
	err := m.Send(Message{To: "a@b.c", Subject: "x", Text: "y"})
	if !errors.Is(err, ErrNotConfigured) {
		t.Fatalf("got %v", err)
	}
}

func TestConfigFromPartsDefaultPort(t *testing.T) {
	cfg := ConfigFromParts(true, "h", "", "u", "p", "f@x")
	if cfg.Port != "587" {
		t.Fatalf("port=%q", cfg.Port)
	}
	if !cfg.Enabled || cfg.Host != "h" || !strings.Contains(cfg.From, "@") {
		t.Fatalf("%+v", cfg)
	}
}

func TestApplyDryRunDisablesSend(t *testing.T) {
	live := ConfigFromParts(true, "smtp.example.com", "587", "u", "p", "from@example.com")
	dry := ApplyDryRun(true, live)
	if dry.Enabled {
		t.Fatal("dry-run must force Enabled=false")
	}
	if dry.Host != "smtp.example.com" {
		t.Fatalf("host should be preserved, got %q", dry.Host)
	}
	if ApplyDryRun(false, live).Enabled != true {
		t.Fatal("dry-run=false must leave Enabled intact")
	}
	m := New(dry)
	if m.Enabled() {
		t.Fatal("New(ApplyDryRun(...)) must be noop")
	}
}