package aws

import (
	"context"
	"errors"
	"testing"
	"time"

	mailx "code.yun.ink/pkg/mailx"
	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/request"
	"github.com/aws/aws-sdk-go/service/ses"
	"github.com/aws/aws-sdk-go/service/ses/sesiface"
)

// mockSES 通过嵌入 sesiface.SESAPI 实现 mock，仅覆盖 SendEmailWithContext
type mockSES struct {
	sesiface.SESAPI
	sendErr error
	lastIn  *ses.SendEmailInput
	lastCtx context.Context
}

func (m *mockSES) SendEmailWithContext(ctx aws.Context, input *ses.SendEmailInput, _ ...request.Option) (*ses.SendEmailOutput, error) {
	m.lastCtx = ctx
	m.lastIn = input
	if m.sendErr != nil {
		return nil, m.sendErr
	}
	return &ses.SendEmailOutput{MessageId: aws.String("mock-id")}, nil
}

// TestSendSuccess 验证完整发送流程与输入构造
func TestSendSuccess(t *testing.T) {
	mock := &mockSES{}
	a := &Aws{cfg: Config{Sender: "noreply@example.com"}, svc: mock}

	msg := mailx.NewMessage().
		To("a@example.com", "b@example.com").
		Cc("cc@example.com").
		Bcc("bcc@example.com").
		Subject("hi").
		Text("plain").
		HTML("<b>html</b>").
		ReplyTo("reply@example.com").
		Build()

	if err := a.Send(context.Background(), msg); err != nil {
		t.Fatal(err)
	}

	in := mock.lastIn
	if in == nil {
		t.Fatal("no input captured")
	}
	if *in.Source != "noreply@example.com" {
		t.Errorf("Source = %q", *in.Source)
	}
	if len(in.Destination.ToAddresses) != 2 || len(in.Destination.CcAddresses) != 1 || len(in.Destination.BccAddresses) != 1 {
		t.Errorf("dest addresses wrong: %+v", in.Destination)
	}
	if len(in.ReplyToAddresses) != 1 || *in.ReplyToAddresses[0] != "reply@example.com" {
		t.Errorf("ReplyTo = %+v", in.ReplyToAddresses)
	}
	if in.Message.Body.Html == nil || in.Message.Body.Text == nil {
		t.Errorf("body should have both html and text: %+v", in.Message.Body)
	}
	if *in.Message.Subject.Charset != "UTF-8" {
		t.Errorf("subject charset = %q", *in.Message.Subject.Charset)
	}
}

// TestSendFromFallback 验证 msg.From 为空时回退 cfg.Sender
func TestSendFromFallback(t *testing.T) {
	mock := &mockSES{}
	a := &Aws{cfg: Config{Sender: "cfg-sender@example.com"}, svc: mock}

	msg := mailx.NewMessage().To("a@example.com").Subject("s").Build()
	if err := a.Send(context.Background(), msg); err != nil {
		t.Fatal(err)
	}
	if *mock.lastIn.Source != "cfg-sender@example.com" {
		t.Errorf("Source = %q, want cfg-sender", *mock.lastIn.Source)
	}
}

// TestSendFail 验证发送失败包装为 ErrSendFailed
func TestSendFail(t *testing.T) {
	mock := &mockSES{sendErr: errors.New("aws down")}
	a := &Aws{cfg: Config{Sender: "s@example.com"}, svc: mock}

	msg := mailx.NewMessage().To("a@example.com").Subject("s").Build()
	err := a.Send(context.Background(), msg)
	if err == nil || !errors.Is(err, mailx.ErrSendFailed) {
		t.Fatalf("err = %v, want ErrSendFailed", err)
	}
}

// TestSendNoSender 验证缺少 Sender 时报错且不调用 SDK
func TestSendNoSender(t *testing.T) {
	mock := &mockSES{}
	a := &Aws{cfg: Config{}, svc: mock}

	msg := mailx.NewMessage().To("a@example.com").Subject("s").Build()
	err := a.Send(context.Background(), msg)
	if err == nil || !errors.Is(err, mailx.ErrInvalidConfig) {
		t.Fatalf("err = %v, want ErrInvalidConfig", err)
	}
	if mock.lastIn != nil {
		t.Error("SDK should not be called")
	}
}

// TestSendInlineError 验证内嵌图片返回明确错误
func TestSendInlineError(t *testing.T) {
	mock := &mockSES{}
	a := &Aws{cfg: Config{Sender: "s@example.com"}, svc: mock}

	msg := mailx.NewMessage().To("a@example.com").Subject("s").
		InlineImageBytes("cid1", "a.png", []byte{1}).
		Build()
	err := a.Send(context.Background(), msg)
	if err == nil || !errors.Is(err, mailx.ErrInvalidConfig) {
		t.Fatalf("err = %v, want ErrInvalidConfig", err)
	}
}

// TestAwsBody 验证 awsBody 各分支
func TestAwsBody(t *testing.T) {
	// 仅 HTML
	b := awsBody(&mailx.Message{Body: "<b>hi</b>"})
	if b.Html == nil || b.Text != nil {
		t.Errorf("html only: %+v", b)
	}
	// 仅 Text
	b = awsBody(&mailx.Message{TextBody: "plain"})
	if b.Html != nil || b.Text == nil {
		t.Errorf("text only: %+v", b)
	}
	// 两者都有
	b = awsBody(&mailx.Message{Body: "<b>hi</b>", TextBody: "plain"})
	if b.Html == nil || b.Text == nil {
		t.Errorf("both: %+v", b)
	}
	// 都没有
	b = awsBody(&mailx.Message{})
	if b.Html != nil || b.Text != nil {
		t.Errorf("neither: %+v", b)
	}
}

// TestWithTimeout 验证超时叠加逻辑
func TestWithTimeout(t *testing.T) {
	ctx := context.Background()

	// 未配置 Timeout：原样返回
	a := &Aws{cfg: Config{}}
	c, cancel := a.withTimeout(ctx)
	if c != ctx {
		t.Error("no timeout should return original ctx")
	}
	cancel()

	// 配置了 Timeout：返回带 deadline 的 ctx
	a = &Aws{cfg: Config{Timeout: time.Second}}
	c, cancel = a.withTimeout(ctx)
	if c == ctx {
		t.Error("with timeout should return new ctx")
	}
	if _, ok := c.Deadline(); !ok {
		t.Error("new ctx should have deadline")
	}
	cancel()

	// ctx 已有更早 deadline：保持原 ctx
	early, ecancel := context.WithTimeout(ctx, time.Millisecond)
	defer ecancel()
	c, cancel = a.withTimeout(early)
	if c != early {
		t.Error("earlier deadline should keep original ctx")
	}
	cancel()
}