package aliyun

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

	mailx "code.yun.ink/pkg/mailx"
	dm20151123 "github.com/alibabacloud-go/dm-20151123/v2/client"
	util "github.com/alibabacloud-go/tea-utils/v2/service"
	"github.com/alibabacloud-go/tea/tea"
)

// mockDM 实现 dmMailer 接口，记录请求并可按需返回错误
type mockDM struct {
	sendErr   error
	statsErr  error
	lastSend  *dm20151123.SingleSendMailRequest
	lastStats *dm20151123.SenderStatisticsDetailByParamRequest

	// statsPages 模拟分页返回；nil 时返回单个空页
	statsPages []*dm20151123.SenderStatisticsDetailByParamResponse
}

func (m *mockDM) SingleSendMailWithOptions(req *dm20151123.SingleSendMailRequest, _ *util.RuntimeOptions) (*dm20151123.SingleSendMailResponse, error) {
	m.lastSend = req
	if m.sendErr != nil {
		return nil, m.sendErr
	}
	return &dm20151123.SingleSendMailResponse{}, nil
}

func (m *mockDM) SenderStatisticsDetailByParamWithOptions(req *dm20151123.SenderStatisticsDetailByParamRequest, _ *util.RuntimeOptions) (*dm20151123.SenderStatisticsDetailByParamResponse, error) {
	m.lastStats = req
	if m.statsErr != nil {
		return nil, m.statsErr
	}
	if len(m.statsPages) > 0 {
		resp := m.statsPages[0]
		m.statsPages = m.statsPages[1:]
		return resp, nil
	}
	return &dm20151123.SenderStatisticsDetailByParamResponse{Body: &dm20151123.SenderStatisticsDetailByParamResponseBody{}}, nil
}

// TestSendSuccess 验证完整发送流程与请求构造
func TestSendSuccess(t *testing.T) {
	mock := &mockDM{}
	a := &Aliyun{cfg: Config{AccountName: "noreply@example.com", ReplyAddress: "r@example.com"}, client: mock}

	msg := mailx.NewMessage().
		To("a@example.com", "b@example.com").
		Subject("hi").
		HTML("<b>html</b>").
		Build()

	if err := a.Send(context.Background(), msg); err != nil {
		t.Fatal(err)
	}
	req := mock.lastSend
	if req == nil {
		t.Fatal("no request captured")
	}
	if tea.StringValue(req.AccountName) != "noreply@example.com" {
		t.Errorf("AccountName = %q", tea.StringValue(req.AccountName))
	}
	if tea.StringValue(req.ToAddress) != "a@example.com,b@example.com" {
		t.Errorf("ToAddress = %q", tea.StringValue(req.ToAddress))
	}
	if tea.StringValue(req.Subject) != "hi" {
		t.Errorf("Subject = %q", tea.StringValue(req.Subject))
	}
	if tea.StringValue(req.HtmlBody) != "<b>html</b>" {
		t.Errorf("HtmlBody = %q", tea.StringValue(req.HtmlBody))
	}
	if tea.BoolValue(req.ReplyToAddress) {
		t.Errorf("ReplyToAddress = %v, want false (uses custom ReplyAddress)", tea.BoolValue(req.ReplyToAddress))
	}
	if tea.StringValue(req.ReplyAddress) != "r@example.com" {
		t.Errorf("ReplyAddress = %q", tea.StringValue(req.ReplyAddress))
	}
}

// TestSendTextOnly 验证纯文本正文被转义为 HTML
func TestSendTextOnly(t *testing.T) {
	mock := &mockDM{}
	a := &Aliyun{cfg: Config{AccountName: "noreply@example.com"}, client: mock}

	msg := mailx.NewMessage().To("a@example.com").Subject("s").Text("a < b & c").Build()
	if err := a.Send(context.Background(), msg); err != nil {
		t.Fatal(err)
	}
	got := tea.StringValue(mock.lastSend.HtmlBody)
	if got != "a &lt; b &amp; c" {
		t.Errorf("escaped HtmlBody = %q", got)
	}
}

// TestSendMsgReplyTo 验证 msg.ReplyTo 优先于 cfg.ReplyAddress
func TestSendMsgReplyTo(t *testing.T) {
	mock := &mockDM{}
	a := &Aliyun{cfg: Config{AccountName: "noreply@example.com", ReplyAddress: "cfg@example.com"}, client: mock}

	msg := mailx.NewMessage().To("a@example.com").Subject("s").ReplyTo("msg@example.com").Build()
	if err := a.Send(context.Background(), msg); err != nil {
		t.Fatal(err)
	}
	if tea.StringValue(mock.lastSend.ReplyAddress) != "msg@example.com" {
		t.Errorf("ReplyAddress = %q, want msg@example.com", tea.StringValue(mock.lastSend.ReplyAddress))
	}
}

// TestSendNoReplyTo 验证无回复地址时 ReplyToAddress=true
func TestSendNoReplyTo(t *testing.T) {
	mock := &mockDM{}
	a := &Aliyun{cfg: Config{AccountName: "noreply@example.com"}, client: mock}

	msg := mailx.NewMessage().To("a@example.com").Subject("s").Build()
	if err := a.Send(context.Background(), msg); err != nil {
		t.Fatal(err)
	}
	if !tea.BoolValue(mock.lastSend.ReplyToAddress) {
		t.Errorf("ReplyToAddress = %v, want true", tea.BoolValue(mock.lastSend.ReplyToAddress))
	}
}

// TestSendTooManyRecipients 验证超过 100 收件人报错
func TestSendTooManyRecipients(t *testing.T) {
	mock := &mockDM{}
	a := &Aliyun{cfg: Config{AccountName: "noreply@example.com"}, client: mock}

	to := make([]string, 101)
	for i := range to {
		to[i] = "u@example.com"
	}
	msg := mailx.NewMessage().To(to...).Subject("s").Build()
	err := a.Send(context.Background(), msg)
	if err == nil || !errors.Is(err, mailx.ErrInvalidMessage) {
		t.Fatalf("err = %v, want ErrInvalidMessage", err)
	}
}

// TestSendNoAccount 验证缺少 AccountName 报错
func TestSendNoAccount(t *testing.T) {
	a := &Aliyun{cfg: Config{}, client: &mockDM{}}
	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)
	}
}

// TestSendInlineError 验证内嵌图片报错
func TestSendInlineError(t *testing.T) {
	a := &Aliyun{cfg: Config{AccountName: "noreply@example.com"}, client: &mockDM{}}
	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)
	}
}

// TestSendFail 验证发送失败包装为 ErrSendFailed
func TestSendFail(t *testing.T) {
	mock := &mockDM{sendErr: errors.New("aliyun down")}
	a := &Aliyun{cfg: Config{AccountName: "noreply@example.com"}, client: 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)
	}
}

// TestRuntimeOptions 验证超时计算
func TestRuntimeOptions(t *testing.T) {
	// 默认超时 30s
	a := &Aliyun{cfg: Config{}}
	ro := a.runtimeOptions(context.Background())
	if ro == nil {
		t.Fatal("runtime options nil")
	}
	// 配置超时 1s
	a = &Aliyun{cfg: Config{Timeout: time.Second}}
	ro = a.runtimeOptions(context.Background())
	// ctx 已有更早 deadline
	early, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
	defer cancel()
	ro = a.runtimeOptions(early)
	_ = ro // 只要不 panic 即可
}

// TestSyncStatusSuccess 验证状态同步记录映射
func TestSyncStatusSuccess(t *testing.T) {
	mock := &mockDM{
		statsPages: []*dm20151123.SenderStatisticsDetailByParamResponse{
			{
				Body: &dm20151123.SenderStatisticsDetailByParamResponseBody{
					Data: &dm20151123.SenderStatisticsDetailByParamResponseBodyData{
						MailDetail: []*dm20151123.SenderStatisticsDetailByParamResponseBodyDataMailDetail{
							{
								AccountName:    tea.String("noreply@example.com"),
								ToAddress:      tea.String("a@example.com"),
								Subject:        tea.String("hi"),
								Status:         tea.Int32(0),
								Message:        tea.String(""),
								LastUpdateTime: tea.String("2026-08-15T10:00Z"),
							},
							{
								AccountName:    tea.String("noreply@example.com"),
								ToAddress:      tea.String("b@example.com"),
								Subject:        tea.String("bye"),
								Status:         tea.Int32(4),
								Message:        tea.String("rejected"),
								LastUpdateTime: tea.String("2026-08-15T11:00Z"),
							},
						},
					},
					NextStart: tea.String("page2"),
				},
			},
			{
				Body: &dm20151123.SenderStatisticsDetailByParamResponseBody{
					Data: &dm20151123.SenderStatisticsDetailByParamResponseBodyData{
						MailDetail: []*dm20151123.SenderStatisticsDetailByParamResponseBodyDataMailDetail{
							{
								ToAddress: tea.String("c@example.com"),
								Subject:   tea.String("page2 mail"),
								Status:    tea.Int32(2),
							},
						},
					},
				},
			},
		},
	}
	a := &Aliyun{cfg: Config{}, client: mock}

	records, err := a.SyncStatus(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if len(records) != 3 {
		t.Fatalf("records len = %d, want 3 (pagination)", len(records))
	}
	if records[0].Status != mailx.EmailSendStatusSuccess {
		t.Errorf("records[0].Status = %v, want Success", records[0].Status)
	}
	if records[1].Status != mailx.EmailSendStatusFailed {
		t.Errorf("records[1].Status = %v, want Failed", records[1].Status)
	}
	if records[1].ErrorMessage != "rejected" {
		t.Errorf("records[1].ErrorMessage = %q", records[1].ErrorMessage)
	}
	if records[2].Status != mailx.EmailSendStatusInvalidAddress {
		t.Errorf("records[2].Status = %v, want InvalidAddress", records[2].Status)
	}
	// 验证第二页请求带 NextStart
	if mock.lastStats == nil || tea.StringValue(mock.lastStats.NextStart) != "page2" {
		t.Errorf("second page NextStart = %v", mock.lastStats)
	}
}

// TestSyncStatusFail 验证状态同步失败包装错误
func TestSyncStatusFail(t *testing.T) {
	mock := &mockDM{statsErr: errors.New("api error")}
	a := &Aliyun{cfg: Config{}, client: mock}
	if _, err := a.SyncStatus(context.Background()); err == nil {
		t.Fatal("SyncStatus should error")
	}
}

// TestNewClientReuse 验证 client 惰性复用（只初始化一次）
func TestNewClientReuse(t *testing.T) {
	a := New(Config{AccessKeyID: "ak", AccessKeySecret: "sk", AccountName: "n@e.com"})
	c1, err := a.newClient()
	if err != nil {
		t.Fatal(err)
	}
	c2, err := a.newClient()
	if err != nil {
		t.Fatal(err)
	}
	if c1 != c2 {
		t.Error("client should be reused")
	}
}