from __future__ import annotations

import json
import uuid

from sqlalchemy import delete, select
from sqlalchemy.ext.asyncio import AsyncSession

from app.models.study_role_permission import StudyRolePermission
from app.models.api_endpoint_permission import ApiEndpointPermission
from app.core.api_permissions import API_ENDPOINT_PERMISSIONS, MODULE_TO_ENDPOINTS
from app.core.permission_cache import get_permission_cache

PROJECT_PERMISSION_ROLES = ("ADMIN", "PM", "CRA", "PV", "MEDICAL_REVIEW", "IMP", "QA")

PROJECT_PERMISSION_MODULES = (
    {"key": "project_members", "label": "项目成员", "description": "维护项目账号、成员角色与启停状态"},
    {"key": "sites", "label": "中心管理", "description": "维护中心资料与 CRA 绑定"},
    {"key": "audit_export", "label": "审计日志导出", "description": "导出项目审计日志"},
    {"key": "project_overview", "label": "项目总览", "description": "查看项目整体进度与中心概览", "writable": False},
    {"key": "project_milestones", "label": "项目里程碑", "description": "维护项目级里程碑"},
    {"key": "fees", "label": "合同费用管理", "description": "维护合同、费用与付款"},
    {"key": "materials", "label": "物资管理", "description": "维护药品出入库与物资设备"},
    {"key": "file_versions", "label": "文件版本管理", "description": "维护文件版本、分发与确认"},
    {"key": "startup_ethics", "label": "立项与伦理", "description": "维护立项、可行性与伦理资料"},
    {"key": "startup_auth", "label": "启动与授权", "description": "维护启动会、培训与授权"},
    {"key": "subjects", "label": "参与者管理", "description": "维护参与者、访视与 PD"},
    {"key": "risk_issues", "label": "风险问题", "description": "维护 SAE、PD 与监查问题"},
    {"key": "monitoring_audit", "label": "监查稽查", "description": "维护监查稽查记录"},
    {"key": "etmf", "label": "eTMF", "description": "维护 eTMF 文件"},
    {"key": "faq", "label": "FAQ", "description": "维护项目 FAQ 分类、问题与回复"},
    {"key": "shared_library", "label": "共享库", "description": "维护注意事项、支持性文件与说明文件"},
)
MANAGEMENT_BACKEND_PERMISSION_MODULES = {"project_members", "sites", "audit_export"}
READ_ONLY_PERMISSION_MODULES = {
    module["key"]
    for module in PROJECT_PERMISSION_MODULES
    if module.get("writable") is False
}

DEFAULT_PROJECT_ROLE_PERMISSIONS: dict[str, dict[str, dict[str, bool]]] = {
    "ADMIN": {
        module["key"]: {"read": True, "write": module["key"] not in READ_ONLY_PERMISSION_MODULES}
        for module in PROJECT_PERMISSION_MODULES
    },
    "PM": {
        "project_overview": {"read": True, "write": False},
        "project_milestones": {"read": True, "write": True},
        "fees": {"read": True, "write": True},
        "materials": {"read": True, "write": True},
        "file_versions": {"read": True, "write": True},
        "startup_ethics": {"read": True, "write": True},
        "startup_auth": {"read": True, "write": True},
        "subjects": {"read": True, "write": True},
        "risk_issues": {"read": True, "write": True},
        "monitoring_audit": {"read": True, "write": True},
        "etmf": {"read": True, "write": True},
        "faq": {"read": True, "write": True},
        "shared_library": {"read": True, "write": True},
        "project_members": {"read": True, "write": True},
        "sites": {"read": True, "write": True},
        "audit_export": {"read": True, "write": False},
    },
    "CRA": {
        "project_overview": {"read": True, "write": False},
        "project_milestones": {"read": True, "write": True},
        "fees": {"read": True, "write": True},
        "materials": {"read": True, "write": True},
        "file_versions": {"read": True, "write": True},
        "startup_ethics": {"read": True, "write": True},
        "startup_auth": {"read": True, "write": True},
        "subjects": {"read": True, "write": True},
        "risk_issues": {"read": True, "write": True},
        "monitoring_audit": {"read": True, "write": True},
        "etmf": {"read": True, "write": True},
        "faq": {"read": True, "write": True},
        "shared_library": {"read": True, "write": True},
        "project_members": {"read": False, "write": False},
        "sites": {"read": False, "write": False},
        "audit_export": {"read": True, "write": False},
    },
    "PV": {
        "project_overview": {"read": True, "write": False},
        "project_milestones": {"read": True, "write": False},
        "fees": {"read": True, "write": False},
        "materials": {"read": True, "write": False},
        "file_versions": {"read": True, "write": False},
        "startup_ethics": {"read": True, "write": False},
        "startup_auth": {"read": True, "write": False},
        "subjects": {"read": True, "write": False},
        "risk_issues": {"read": True, "write": True},
        "monitoring_audit": {"read": True, "write": True},
        "etmf": {"read": True, "write": False},
        "faq": {"read": True, "write": True},
        "shared_library": {"read": True, "write": True},
        "project_members": {"read": False, "write": False},
        "sites": {"read": False, "write": False},
        "audit_export": {"read": False, "write": False},
    },
    "MEDICAL_REVIEW": {
        "project_overview": {"read": True, "write": False},
        "project_milestones": {"read": False, "write": False},
        "fees": {"read": False, "write": False},
        "materials": {"read": False, "write": False},
        "file_versions": {"read": False, "write": False},
        "startup_ethics": {"read": False, "write": False},
        "startup_auth": {"read": False, "write": False},
        "subjects": {"read": True, "write": False},
        "risk_issues": {"read": True, "write": True},
        "monitoring_audit": {"read": True, "write": False},
        "etmf": {"read": False, "write": False},
        "faq": {"read": True, "write": True},
        "shared_library": {"read": True, "write": True},
        "project_members": {"read": False, "write": False},
        "sites": {"read": False, "write": False},
        "audit_export": {"read": False, "write": False},
    },
    "IMP": {
        "project_overview": {"read": True, "write": False},
        "project_milestones": {"read": True, "write": False},
        "fees": {"read": True, "write": False},
        "materials": {"read": True, "write": True},
        "file_versions": {"read": True, "write": True},
        "startup_ethics": {"read": True, "write": False},
        "startup_auth": {"read": True, "write": True},
        "subjects": {"read": True, "write": False},
        "risk_issues": {"read": True, "write": False},
        "monitoring_audit": {"read": True, "write": False},
        "etmf": {"read": True, "write": False},
        "faq": {"read": True, "write": True},
        "shared_library": {"read": True, "write": True},
        "project_members": {"read": False, "write": False},
        "sites": {"read": False, "write": False},
        "audit_export": {"read": False, "write": False},
    },
    "QA": {
        "project_overview": {"read": True, "write": False},
        "project_milestones": {"read": True, "write": False},
        "fees": {"read": True, "write": False},
        "materials": {"read": True, "write": False},
        "file_versions": {"read": True, "write": False},
        "startup_ethics": {"read": True, "write": False},
        "startup_auth": {"read": True, "write": False},
        "subjects": {"read": True, "write": False},
        "risk_issues": {"read": True, "write": False},
        "monitoring_audit": {"read": True, "write": True},
        "etmf": {"read": True, "write": False},
        "faq": {"read": True, "write": False},
        "shared_library": {"read": True, "write": True},
        "project_members": {"read": False, "write": False},
        "sites": {"read": False, "write": False},
        "audit_export": {"read": False, "write": False},
    },
}


def _empty_action_state() -> dict[str, bool]:
    return {"read": False, "write": False}


def _normalize_action_state(value: dict | None, role: str) -> dict[str, bool]:
    if role == "ADMIN":
        return {"read": True, "write": True}
    read = bool((value or {}).get("read", False))
    write = bool((value or {}).get("write", False))
    if write:
        read = True
    return {"read": read, "write": write}


def _normalize_module_action_state(value: dict | None, role: str, module: str) -> dict[str, bool]:
    if role == "ADMIN":
        return {"read": True, "write": module not in READ_ONLY_PERMISSION_MODULES}
    if module in MANAGEMENT_BACKEND_PERMISSION_MODULES and role != "PM":
        return _empty_action_state()
    if module in READ_ONLY_PERMISSION_MODULES:
        return {"read": bool((value or {}).get("read", False) or (value or {}).get("write", False)), "write": False}
    return _normalize_action_state(value, role)


def normalize_permission_matrix(matrix: dict | None = None) -> dict[str, dict[str, dict[str, bool]]]:
    normalized: dict[str, dict[str, dict[str, bool]]] = {}
    matrix = matrix or {}
    for role in PROJECT_PERMISSION_ROLES:
        normalized[role] = {}
        role_matrix = matrix.get(role) or DEFAULT_PROJECT_ROLE_PERMISSIONS.get(role, {})
        for module in PROJECT_PERMISSION_MODULES:
            module_key = module["key"]
            normalized[role][module_key] = _normalize_module_action_state(
                role_matrix.get(module_key, _empty_action_state()),
                role,
                module_key,
            )
    return normalized


async def get_project_role_permissions(db: AsyncSession, study_id: uuid.UUID) -> dict[str, dict[str, dict[str, bool]]]:
    result = await db.execute(select(StudyRolePermission).where(StudyRolePermission.study_id == study_id))
    rows = result.scalars().all()
    if not rows:
        return normalize_permission_matrix(DEFAULT_PROJECT_ROLE_PERMISSIONS)
    matrix = normalize_permission_matrix(DEFAULT_PROJECT_ROLE_PERMISSIONS)
    for row in rows:
        if row.role not in PROJECT_PERMISSION_ROLES:
            continue
        if row.module not in matrix[row.role]:
            continue
        matrix[row.role][row.module] = _normalize_module_action_state(
            {"read": row.can_read, "write": row.can_write},
            row.role,
            row.module,
        )
    return matrix


async def replace_project_role_permissions(
    db: AsyncSession,
    study_id: uuid.UUID,
    payload: dict[str, dict[str, dict[str, bool]]],
) -> dict[str, dict[str, dict[str, bool]]]:
    matrix = normalize_permission_matrix(payload)
    await db.execute(delete(StudyRolePermission).where(StudyRolePermission.study_id == study_id))
    for role, role_matrix in matrix.items():
        if role == "ADMIN":
            continue
        for module, actions in role_matrix.items():
            db.add(
                StudyRolePermission(
                    study_id=study_id,
                    role=role,
                    module=module,
                    can_read=actions["read"],
                    can_write=actions["write"],
                )
            )
    await db.commit()

    # 失效缓存
    cache = get_permission_cache()
    cache.invalidate_project_permissions(study_id)
    cache.invalidate_all_member_roles(study_id)

    return matrix


async def role_has_project_permission(
    db: AsyncSession,
    study_id: uuid.UUID,
    role: str | None,
    module: str,
    action: str,
) -> bool:
    if role == "ADMIN":
        return True
    matrix = await get_project_role_permissions(db, study_id)
    actions = matrix.get(role or "", {}).get(module)
    if not actions:
        return False
    if action == "write":
        return bool(actions["write"])
    return bool(actions["read"])


async def role_has_api_permission(
    db: AsyncSession,
    study_id: uuid.UUID,
    role: str | None,
    endpoint_key: str,
) -> bool:
    """检查角色是否有权访问特定接口

    权限检查优先级：
    1. 接口级权限（如果已配置）
    2. 模块级权限（向后兼容）
    """
    if role == "ADMIN":
        return True

    # 1. 先查询接口级权限
    result = await db.execute(
        select(ApiEndpointPermission).where(
            ApiEndpointPermission.study_id == study_id,
            ApiEndpointPermission.role == role,
            ApiEndpointPermission.endpoint_key == endpoint_key,
        )
    )
    perm = result.scalar_one_or_none()
    if perm is not None:
        return perm.allowed

    # 2. 如果没有接口级权限，回退到模块级权限（向后兼容）
    endpoint_config = API_ENDPOINT_PERMISSIONS.get(endpoint_key)
    if not endpoint_config:
        return False

    module = endpoint_config["module"]
    action = endpoint_config["action"]
    return await role_has_project_permission(db, study_id, role, module, action)


async def get_api_endpoint_permissions(
    db: AsyncSession,
    study_id: uuid.UUID,
) -> dict[str, dict[str, dict[str, bool]]]:
    """获取项目的接口级权限矩阵

    返回格式: {role: {endpoint_key: {allowed: bool}}}
    """
    result = await db.execute(
        select(ApiEndpointPermission).where(
            ApiEndpointPermission.study_id == study_id,
        )
    )
    rows = result.scalars().all()

    # 初始化矩阵，包含所有角色和端点的默认权限
    matrix: dict[str, dict[str, dict[str, bool]]] = {}
    for role in PROJECT_PERMISSION_ROLES:
        if role == "ADMIN":
            continue
        matrix[role] = {}
        for endpoint_key, config in API_ENDPOINT_PERMISSIONS.items():
            default_allowed = role in config.get("default_roles", [])
            matrix[role][endpoint_key] = {"allowed": default_allowed}

    # 覆盖自定义权限
    for row in rows:
        if row.role not in matrix:
            matrix[row.role] = {}
        matrix[row.role][row.endpoint_key] = {"allowed": row.allowed}

    return matrix


async def replace_api_endpoint_permissions(
    db: AsyncSession,
    study_id: uuid.UUID,
    payload: dict[str, dict[str, bool]],
) -> dict[str, dict[str, dict[str, bool]]]:
    """替换项目的接口级权限矩阵

    参数:
        payload: {role: {endpoint_key: allowed}}

    返回格式: {role: {endpoint_key: {allowed: bool}}}
    """
    # 删除该项目的所有接口级权限
    await db.execute(
        delete(ApiEndpointPermission).where(
            ApiEndpointPermission.study_id == study_id,
        )
    )

    # 插入新的权限配置
    for role, endpoints in payload.items():
        if role == "ADMIN":
            continue
        for endpoint_key, allowed in endpoints.items():
            if endpoint_key not in API_ENDPOINT_PERMISSIONS:
                continue
            db.add(
                ApiEndpointPermission(
                    study_id=study_id,
                    role=role,
                    endpoint_key=endpoint_key,
                    allowed=allowed,
                )
            )

    await db.commit()

    # 失效缓存
    cache = get_permission_cache()
    cache.invalidate_project_permissions(study_id)
    cache.invalidate_all_member_roles(study_id)

    return await get_api_endpoint_permissions(db, study_id)