import pytest
from unittest.mock import Mock, patch, MagicMock
from app.services.email_service import (
    EmailService,
    EmailMessage,
    EmailSendResult,
    EMAIL_TEMPLATES,
)


class TestEmailMessage:
    """邮件消息数据结构测试"""

    def test_email_message_creation(self):
        """测试EmailMessage数据创建"""
        msg = EmailMessage(
            to="test@example.com",
            subject="测试邮件",
            body_html="<h1>测试</h1>",
            body_text="测试邮件",
        )
        assert msg.to == "test@example.com"
        assert msg.subject == "测试邮件"
        assert msg.body_html == "<h1>测试</h1>"
        assert msg.body_text == "测试邮件"
        assert msg.attachments == []
        assert msg.metadata == {}

    def test_email_message_with_attachments(self):
        """测试带附件的邮件消息"""
        msg = EmailMessage(
            to="test@example.com",
            subject="带附件",
            body_html="<p>内容</p>",
            body_text="内容",
            attachments=[{"filename": "report.pdf", "content": b"data"}],
        )
        assert len(msg.attachments) == 1
        assert msg.attachments[0]["filename"] == "report.pdf"

    def test_email_message_with_metadata(self):
        """测试带元数据的邮件消息"""
        msg = EmailMessage(
            to="test@example.com",
            subject="测试",
            body_html="<p>内容</p>",
            body_text="内容",
            metadata={"brand_name": "test_brand", "alert_type": "error"},
        )
        assert msg.metadata["brand_name"] == "test_brand"


class TestEmailSendResult:
    """邮件发送结果数据结构测试"""

    def test_email_send_result_success(self):
        """测试成功发送结果"""
        result = EmailSendResult(
            success=True,
            message_id="msg_123",
            error=None,
            retry_count=0,
        )
        assert result.success is True
        assert result.message_id == "msg_123"
        assert result.error is None
        assert result.retry_count == 0

    def test_email_send_result_failure(self):
        """测试失败发送结果"""
        result = EmailSendResult(
            success=False,
            message_id=None,
            error="SMTP连接失败",
            retry_count=3,
        )
        assert result.success is False
        assert result.message_id is None
        assert result.error == "SMTP连接失败"
        assert result.retry_count == 3


class TestEmailTemplateRendering:
    """邮件模板渲染测试"""

    @pytest.fixture
    def email_service(self):
        """创建邮件服务实例"""
        return EmailService()

    def test_render_alert_notification_template(self, email_service):
        """测试告警通知模板渲染"""
        variables = {
            "alert_type": "系统错误",
            "brand_name": "测试品牌",
            "severity": "高",
            "description": "数据库连接失败",
            "timestamp": "2024-01-01 12:00:00",
        }
        msg = email_service.render_template("alert_notification", "admin@example.com", variables)
        
        assert msg.to == "admin@example.com"
        assert "[GEO平台] 告警通知：系统错误" in msg.subject
        assert "测试品牌" in msg.body_html
        assert "系统错误" in msg.body_html
        assert "高" in msg.body_html

    def test_render_quota_warning_template(self, email_service):
        """测试额度预警模板渲染"""
        variables = {
            "quota_type": "API调用",
            "usage_percentage": 85,
            "used": 850,
            "limit": 1000,
            "recommended_action": "请升级套餐",
        }
        msg = email_service.render_template("quota_warning", "user@example.com", variables)
        
        assert msg.to == "user@example.com"
        assert "[GEO平台] 额度预警：API调用" in msg.subject
        assert "85%" in msg.body_html
        assert "850" in msg.body_html
        assert "1000" in msg.body_html

    def test_render_template_missing_variables(self, email_service):
        """测试模板渲染缺少变量"""
        variables = {"alert_type": "系统错误"}
        msg = email_service.render_template("alert_notification", "admin@example.com", variables)
        
        assert msg is not None
        assert msg.to == "admin@example.com"

    def test_render_template_invalid_template(self, email_service):
        """测试无效模板名称"""
        with pytest.raises(ValueError, match="模板不存在"):
            email_service.render_template(
                "invalid_template",
                "admin@example.com",
                {"key": "value"},
            )

    def test_render_template_variable_substitution(self, email_service):
        """测试模板变量替换"""
        variables = {
            "brand_name": "品牌A",
            "alert_type": "告警B",
            "severity": "严重",
            "description": "描述C",
            "timestamp": "时间D",
        }
        msg = email_service.render_template("alert_notification", "test@example.com", variables)
        
        assert "品牌A" in msg.body_html
        assert "告警B" in msg.body_html
        assert "严重" in msg.body_html
        assert "描述C" in msg.body_html
        assert "时间D" in msg.body_html


class TestEmailGeneration:
    """邮件内容生成测试"""

    @pytest.fixture
    def email_service(self):
        """创建邮件服务实例"""
        return EmailService()

    def test_generate_alert_notification_email(self, email_service):
        """测试生成告警通知邮件"""
        msg = email_service.generate_alert_email(
            to="admin@example.com",
            alert_type="数据库告警",
            brand_name="测试品牌",
            severity="高",
            description="数据库CPU使用率超过90%",
            timestamp="2024-01-01 12:00:00",
        )
        
        assert msg.to == "admin@example.com"
        assert "数据库告警" in msg.subject
        assert "测试品牌" in msg.body_html
        assert "高" in msg.body_html
        assert msg.body_text != ""

    def test_generate_quota_warning_email(self, email_service):
        """测试生成额度预警邮件"""
        msg = email_service.generate_quota_warning_email(
            to="user@example.com",
            quota_type="API调用",
            usage_percentage=85,
            used=850,
            limit=1000,
            recommended_action="建议升级套餐",
        )
        
        assert msg.to == "user@example.com"
        assert "API调用" in msg.subject
        assert "85%" in msg.body_html
        assert "850" in msg.body_html
        assert "1000" in msg.body_html

    def test_generate_email_has_both_formats(self, email_service):
        """测试生成的邮件包含HTML和纯文本格式"""
        msg = email_service.generate_alert_email(
            to="test@example.com",
            alert_type="测试",
            brand_name="品牌",
            severity="中",
            description="描述",
            timestamp="时间",
        )
        
        assert msg.body_html != ""
        assert msg.body_text != ""
        assert "<" in msg.body_html
        assert "<" not in msg.body_text


class TestEmailSending:
    """邮件发送测试"""

    @pytest.fixture
    def email_service(self):
        """创建邮件服务实例（模拟模式）"""
        return EmailService(simulate_mode=True)

    def test_send_email_simulate_mode(self, email_service):
        """测试模拟模式发送邮件"""
        msg = EmailMessage(
            to="test@example.com",
            subject="测试",
            body_html="<p>测试</p>",
            body_text="测试",
        )
        result = email_service.send_email(msg)
        
        assert result.success is True
        assert result.message_id is not None
        assert result.error is None

    @patch("smtplib.SMTP")
    def test_send_email_real_smtp(self, mock_smtp):
        """测试真实SMTP发送（模拟SMTP）"""
        mock_server = MagicMock()
        mock_smtp.return_value = mock_server
        
        service = EmailService(
            simulate_mode=False,
            smtp_host="smtp.example.com",
            smtp_port=587,
            smtp_user="user@example.com",
            smtp_password="password",
        )
        
        msg = EmailMessage(
            to="recipient@example.com",
            subject="测试",
            body_html="<p>内容</p>",
            body_text="内容",
        )
        
        result = service.send_email(msg)
        
        assert result.success is True
        mock_smtp.assert_called_once_with("smtp.example.com", 587)
        mock_server.starttls.assert_called_once()
        mock_server.login.assert_called_once_with("user@example.com", "password")

    @patch("smtplib.SMTP")
    def test_send_email_smtp_failure(self, mock_smtp):
        """测试SMTP发送失败"""
        mock_smtp.side_effect = Exception("连接失败")
        
        service = EmailService(
            simulate_mode=False,
            smtp_host="smtp.example.com",
            smtp_port=587,
            smtp_user="user@example.com",
            smtp_password="password",
        )
        
        msg = EmailMessage(
            to="test@example.com",
            subject="测试",
            body_html="<p>内容</p>",
            body_text="内容",
        )
        
        result = service.send_email(msg)
        
        assert result.success is False
        assert result.error is not None
        assert "连接失败" in result.error

    @patch("smtplib.SMTP")
    def test_send_email_with_retry(self, mock_smtp):
        """测试邮件发送重试"""
        mock_server = MagicMock()
        mock_smtp.return_value = mock_server
        
        service = EmailService(
            simulate_mode=False,
            smtp_host="smtp.example.com",
            smtp_port=587,
            smtp_user="user@example.com",
            smtp_password="password",
            max_retries=3,
        )
        
        msg = EmailMessage(
            to="test@example.com",
            subject="测试",
            body_html="<p>内容</p>",
            body_text="内容",
        )
        
        result = service.send_email(msg)
        
        assert result.success is True
        assert result.retry_count == 0


class TestEmailQueue:
    """邮件队列测试"""

    @pytest.fixture
    def email_service(self):
        """创建邮件服务实例"""
        return EmailService(simulate_mode=True)

    def test_add_to_queue(self, email_service):
        """测试添加邮件到队列"""
        msg = EmailMessage(
            to="test@example.com",
            subject="测试",
            body_html="<p>内容</p>",
            body_text="内容",
        )
        
        email_service.add_to_queue(msg)
        
        assert len(email_service.get_queue()) == 1
        assert email_service.get_queue()[0].to == "test@example.com"

    def test_add_multiple_to_queue(self, email_service):
        """测试批量添加邮件到队列"""
        messages = [
            EmailMessage(to=f"user{i}@example.com", subject=f"测试{i}", body_html="<p>内容</p>", body_text="内容")
            for i in range(5)
        ]
        
        for msg in messages:
            email_service.add_to_queue(msg)
        
        assert len(email_service.get_queue()) == 5

    def test_send_queue(self, email_service):
        """测试发送队列中的邮件"""
        messages = [
            EmailMessage(to=f"user{i}@example.com", subject=f"测试{i}", body_html="<p>内容</p>", body_text="内容")
            for i in range(3)
        ]
        
        for msg in messages:
            email_service.add_to_queue(msg)
        
        results = email_service.send_queue()
        
        assert len(results) == 3
        assert all(r.success for r in results)
        assert len(email_service.get_queue()) == 0

    def test_send_queue_empty(self, email_service):
        """测试发送空队列"""
        results = email_service.send_queue()
        
        assert results == []

    def test_clear_queue(self, email_service):
        """测试清空队列"""
        msg = EmailMessage(
            to="test@example.com",
            subject="测试",
            body_html="<p>内容</p>",
            body_text="内容",
        )
        email_service.add_to_queue(msg)
        assert len(email_service.get_queue()) == 1
        
        email_service.clear_queue()
        
        assert len(email_service.get_queue()) == 0


class TestEmailAttachments:
    """邮件附件测试"""

    @pytest.fixture
    def email_service(self):
        """创建邮件服务实例"""
        return EmailService(simulate_mode=True)

    def test_add_attachment_to_message(self, email_service):
        """测试添加附件到邮件"""
        msg = EmailMessage(
            to="test@example.com",
            subject="带附件",
            body_html="<p>内容</p>",
            body_text="内容",
        )
        
        email_service.add_attachment(msg, "report.pdf", b"PDF content")
        
        assert len(msg.attachments) == 1
        assert msg.attachments[0]["filename"] == "report.pdf"
        assert msg.attachments[0]["content"] == b"PDF content"

    def test_add_multiple_attachments(self, email_service):
        """测试添加多个附件"""
        msg = EmailMessage(
            to="test@example.com",
            subject="多附件",
            body_html="<p>内容</p>",
            body_text="内容",
        )
        
        email_service.add_attachment(msg, "file1.pdf", b"content1")
        email_service.add_attachment(msg, "file2.xlsx", b"content2")
        
        assert len(msg.attachments) == 2
        assert msg.attachments[0]["filename"] == "file1.pdf"
        assert msg.attachments[1]["filename"] == "file2.xlsx"


class TestEmailValidation:
    """邮箱地址验证测试"""

    @pytest.fixture
    def email_service(self):
        """创建邮件服务实例"""
        return EmailService()

    def test_validate_valid_email(self, email_service):
        """测试有效邮箱地址"""
        assert email_service.validate_email("test@example.com") is True
        assert email_service.validate_email("user.name@domain.org") is True
        assert email_service.validate_email("user+tag@example.com") is True

    def test_validate_invalid_email(self, email_service):
        """测试无效邮箱地址"""
        assert email_service.validate_email("invalid") is False
        assert email_service.validate_email("invalid@") is False
        assert email_service.validate_email("@example.com") is False
        assert email_service.validate_email("test@") is False
        assert email_service.validate_email("") is False

    def test_send_to_invalid_email(self, email_service):
        """测试发送到无效邮箱"""
        msg = EmailMessage(
            to="invalid_email",
            subject="测试",
            body_html="<p>内容</p>",
            body_text="内容",
        )
        
        result = email_service.send_email(msg)
        
        assert result.success is False
        assert result.error is not None


class TestEmailTemplatesConstants:
    """邮件模板常量测试"""

    def test_email_templates_exist(self):
        """测试邮件模板存在"""
        assert "alert_notification" in EMAIL_TEMPLATES
        assert "quota_warning" in EMAIL_TEMPLATES

    def test_alert_notification_template_structure(self):
        """测试告警通知模板结构"""
        template = EMAIL_TEMPLATES["alert_notification"]
        assert "subject" in template
        assert "body_html" in template
        assert "body_text" in template
        assert "{alert_type}" in template["subject"]
        assert "{brand_name}" in template["body_html"]

    def test_quota_warning_template_structure(self):
        """测试额度预警模板结构"""
        template = EMAIL_TEMPLATES["quota_warning"]
        assert "subject" in template
        assert "body_html" in template
        assert "body_text" in template
        assert "{quota_type}" in template["subject"]
        assert "{usage_percentage}" in template["body_html"]