from datetime import date
from typing import Any

from sqlalchemy import select

from app.core.utils.time import utc_now
from app.modules.business.constants import (
    DONE_STATUSES,
    PROJECT_CLOSED_STATUSES,
    SUPPLIER_RISK_LEVELS,
    BusinessDomain,
    RiskEventType,
    RiskLevel,
    StatusValue,
)
from app.modules.business.models import (
    FundAccount,
    Project,
    Supplier,
    WorkTask,
)
from app.modules.business.service import serialize_model
from app.modules.risk.constants import (
    RiskEventPayloadKey,
)


class RiskDetectorMixin:
    def _build_event_payloads(self) -> list[dict[str, Any]]:
        payloads: list[dict[str, Any]] = []
        payloads.extend(self._overdue_task_payloads())
        payloads.extend(self._delayed_project_payloads())
        payloads.extend(self._over_budget_project_payloads())
        payloads.extend(self._fund_risk_payloads())
        payloads.extend(self._supplier_risk_payloads())
        return payloads

    def _overdue_task_payloads(self) -> list[dict[str, Any]]:
        stmt = select(WorkTask).where(
            WorkTask.due_date.is_not(None),
            WorkTask.due_date < date.today(),
            WorkTask.status.notin_(DONE_STATUSES),
        )
        payloads = []
        for task in self.db.execute(stmt).scalars():
            payloads.append(
                {
                    RiskEventPayloadKey.CODE: f"RISK-TASK-OVERDUE-{task.id}",
                    RiskEventPayloadKey.TITLE: f"任务逾期：{task.title}",
                    RiskEventPayloadKey.RISK_TYPE: RiskEventType.OVERDUE_TASK,
                    RiskEventPayloadKey.RISK_LEVEL: RiskLevel.MEDIUM,
                    RiskEventPayloadKey.STATUS: StatusValue.OPEN,
                    RiskEventPayloadKey.SOURCE_DOMAIN: BusinessDomain.TASKS,
                    RiskEventPayloadKey.SOURCE_RECORD_ID: str(task.id),
                    RiskEventPayloadKey.PROJECT_CODE: task.project_code,
                    RiskEventPayloadKey.OWNER: task.owner,
                    RiskEventPayloadKey.DUE_DATE: task.due_date,
                    RiskEventPayloadKey.DETECTED_AT: utc_now(),
                    RiskEventPayloadKey.DESCRIPTION: "任务已超过截止日期且未完成。",
                    RiskEventPayloadKey.MITIGATION: (
                        "请负责人更新进度、明确阻塞项并给出新的完成时间。"
                    ),
                    RiskEventPayloadKey.EVIDENCE: serialize_model(task),
                }
            )
        return payloads

    def _delayed_project_payloads(self) -> list[dict[str, Any]]:
        stmt = select(Project).where(
            Project.due_date.is_not(None),
            Project.due_date < date.today(),
            Project.status.notin_(PROJECT_CLOSED_STATUSES),
        )
        payloads = []
        for project in self.db.execute(stmt).scalars():
            level = RiskLevel.HIGH if project.progress_percent < 80 else RiskLevel.MEDIUM
            payloads.append(
                {
                    RiskEventPayloadKey.CODE: f"RISK-PROJECT-DELAY-{project.id}",
                    RiskEventPayloadKey.TITLE: f"项目延期：{project.name}",
                    RiskEventPayloadKey.RISK_TYPE: RiskEventType.DELAYED_PROJECT,
                    RiskEventPayloadKey.RISK_LEVEL: level,
                    RiskEventPayloadKey.STATUS: StatusValue.OPEN,
                    RiskEventPayloadKey.SOURCE_DOMAIN: BusinessDomain.PROJECTS,
                    RiskEventPayloadKey.SOURCE_RECORD_ID: str(project.id),
                    RiskEventPayloadKey.PROJECT_CODE: project.code,
                    RiskEventPayloadKey.OWNER: project.owner,
                    RiskEventPayloadKey.DUE_DATE: project.due_date,
                    RiskEventPayloadKey.DETECTED_AT: utc_now(),
                    RiskEventPayloadKey.DESCRIPTION: "项目已超过计划截止日期且未进入完成状态。",
                    RiskEventPayloadKey.MITIGATION: (
                        "请项目负责人提交延期原因、资源需求和纠偏计划。"
                    ),
                    RiskEventPayloadKey.EVIDENCE: serialize_model(project),
                }
            )
        return payloads

    def _over_budget_project_payloads(self) -> list[dict[str, Any]]:
        stmt = select(Project).where(
            Project.budget_amount > 0,
            Project.actual_amount > Project.budget_amount,
        )
        payloads = []
        for project in self.db.execute(stmt).scalars():
            payloads.append(
                {
                    RiskEventPayloadKey.CODE: f"RISK-PROJECT-BUDGET-{project.id}",
                    RiskEventPayloadKey.TITLE: f"项目超预算：{project.name}",
                    RiskEventPayloadKey.RISK_TYPE: RiskEventType.OVER_BUDGET_PROJECT,
                    RiskEventPayloadKey.RISK_LEVEL: RiskLevel.HIGH,
                    RiskEventPayloadKey.STATUS: StatusValue.OPEN,
                    RiskEventPayloadKey.SOURCE_DOMAIN: BusinessDomain.PROJECTS,
                    RiskEventPayloadKey.SOURCE_RECORD_ID: str(project.id),
                    RiskEventPayloadKey.PROJECT_CODE: project.code,
                    RiskEventPayloadKey.OWNER: project.owner,
                    RiskEventPayloadKey.DUE_DATE: project.due_date,
                    RiskEventPayloadKey.DETECTED_AT: utc_now(),
                    RiskEventPayloadKey.DESCRIPTION: "项目实际成本已超过预算。",
                    RiskEventPayloadKey.MITIGATION: (
                        "请复核预算科目、冻结非必要采购并补充审批依据。"
                    ),
                    RiskEventPayloadKey.EVIDENCE: serialize_model(project),
                }
            )
        return payloads

    def _fund_risk_payloads(self) -> list[dict[str, Any]]:
        stmt = select(FundAccount).where(FundAccount.current_balance < FundAccount.safety_line)
        payloads = []
        for account in self.db.execute(stmt).scalars():
            payloads.append(
                {
                    RiskEventPayloadKey.CODE: f"RISK-FUND-{account.id}",
                    RiskEventPayloadKey.TITLE: f"资金低于安全线：{account.name}",
                    RiskEventPayloadKey.RISK_TYPE: RiskEventType.FUND_SAFETY_LINE,
                    RiskEventPayloadKey.RISK_LEVEL: RiskLevel.HIGH,
                    RiskEventPayloadKey.STATUS: StatusValue.OPEN,
                    RiskEventPayloadKey.SOURCE_DOMAIN: BusinessDomain.FUND_ACCOUNTS,
                    RiskEventPayloadKey.SOURCE_RECORD_ID: str(account.id),
                    RiskEventPayloadKey.OWNER: None,
                    RiskEventPayloadKey.DETECTED_AT: utc_now(),
                    RiskEventPayloadKey.DESCRIPTION: "账户当前余额低于设置的安全线。",
                    RiskEventPayloadKey.MITIGATION: (
                        "请财务确认收付款计划，"
                        "并优先处理关键项目资金安排。"
                    ),
                    RiskEventPayloadKey.EVIDENCE: serialize_model(account),
                }
            )
        return payloads

    def _supplier_risk_payloads(self) -> list[dict[str, Any]]:
        stmt = select(Supplier).where(
            (Supplier.blacklist_status != StatusValue.NORMAL)
            | Supplier.risk_level.in_(SUPPLIER_RISK_LEVELS)
        )
        payloads = []
        for supplier in self.db.execute(stmt).scalars():
            level = (
                RiskLevel.HIGH
                if supplier.blacklist_status != StatusValue.NORMAL
                else supplier.risk_level
            )
            payloads.append(
                {
                    RiskEventPayloadKey.CODE: f"RISK-SUPPLIER-{supplier.id}",
                    RiskEventPayloadKey.TITLE: f"供应商风险：{supplier.name}",
                    RiskEventPayloadKey.RISK_TYPE: RiskEventType.SUPPLIER_RISK,
                    RiskEventPayloadKey.RISK_LEVEL: level,
                    RiskEventPayloadKey.STATUS: StatusValue.OPEN,
                    RiskEventPayloadKey.SOURCE_DOMAIN: BusinessDomain.SUPPLIERS,
                    RiskEventPayloadKey.SOURCE_RECORD_ID: str(supplier.id),
                    RiskEventPayloadKey.OWNER: supplier.contact,
                    RiskEventPayloadKey.DETECTED_AT: utc_now(),
                    RiskEventPayloadKey.DESCRIPTION: "供应商风险等级或黑名单状态需要关注。",
                    RiskEventPayloadKey.MITIGATION: (
                        "请采购负责人复核供应商准入、履约和替代方案。"
                    ),
                    RiskEventPayloadKey.EVIDENCE: serialize_model(supplier),
                }
            )
        return payloads