"""
场景契约 API — 统一 DSL 输入契约的 CRUD 与预置查询
"""
from fastapi import APIRouter, Depends, HTTPException, Response, status, Query
from sqlalchemy.orm import Session
from pydantic import BaseModel, Field
from typing import Any, Dict, List, Optional
import logging
import uuid

from app.core.database import get_db
from app.api.auth import get_current_user
from app.models.user import User
from app.models.scene_contract import SceneContract
from app.services.scene_contract_service import (
    build_system_prompt_from_contract,
    build_acceptance_prompt,
    validate_input_against_contract,
    get_preset_contract,
    list_preset_contracts_meta,
    PRESET_CONTRACTS,
    ContractPromptConfig,
)

logger = logging.getLogger(__name__)

router = APIRouter(prefix="/api/v1/scene-contracts", tags=["scene-contracts"])


# ── Pydantic schemas ──

class DeliverableItem(BaseModel):
    name: str
    format: Optional[str] = None
    description: Optional[str] = None


class ExampleItem(BaseModel):
    input: str
    output: str


class ContractCreate(BaseModel):
    name: str
    description: Optional[str] = None
    goal: str
    role: Optional[str] = None
    input_description: Optional[str] = None
    input_schema: Optional[Dict[str, Any]] = None
    constraints: List[str] = Field(default_factory=list)
    forbidden_actions: List[str] = Field(default_factory=list)
    required_tools: List[str] = Field(default_factory=list)
    deliverables: List[DeliverableItem] = Field(default_factory=list)
    acceptance_criteria: List[str] = Field(default_factory=list)
    output_schema: Optional[Dict[str, Any]] = None
    examples: List[ExampleItem] = Field(default_factory=list)
    category: Optional[str] = None
    tags: List[str] = Field(default_factory=list)
    is_public: bool = False
    template_binding: Optional[str] = None


class ContractUpdate(BaseModel):
    name: Optional[str] = None
    description: Optional[str] = None
    goal: Optional[str] = None
    role: Optional[str] = None
    input_description: Optional[str] = None
    input_schema: Optional[Dict[str, Any]] = None
    constraints: Optional[List[str]] = None
    forbidden_actions: Optional[List[str]] = None
    required_tools: Optional[List[str]] = None
    deliverables: Optional[List[DeliverableItem]] = None
    acceptance_criteria: Optional[List[str]] = None
    output_schema: Optional[Dict[str, Any]] = None
    examples: Optional[List[ExampleItem]] = None
    category: Optional[str] = None
    tags: Optional[List[str]] = None
    is_public: Optional[bool] = None
    template_binding: Optional[str] = None


class ContractResponse(BaseModel):
    id: str
    name: str
    description: Optional[str] = None
    goal: str
    role: Optional[str] = None
    input_description: Optional[str] = None
    input_schema: Optional[Dict[str, Any]] = None
    constraints: List[str] = []
    forbidden_actions: List[str] = []
    required_tools: List[str] = []
    deliverables: List[Dict[str, Any]] = []
    acceptance_criteria: List[str] = []
    output_schema: Optional[Dict[str, Any]] = None
    examples: List[Dict[str, Any]] = []
    category: Optional[str] = None
    tags: List[str] = []
    version: int = 1
    is_public: int = 0
    use_count: int = 0
    user_id: Optional[str] = None
    template_binding: Optional[str] = None
    created_at: Optional[str] = None
    updated_at: Optional[str] = None


class ContractMetaItem(BaseModel):
    id: str
    name: str
    description: Optional[str] = None
    category: Optional[str] = None
    tags: List[str] = []
    goal: str = ""
    deliverable_count: int = 0
    constraint_count: int = 0


class PromptGenerateRequest(BaseModel):
    contract_id: Optional[str] = None
    contract_data: Optional[Dict[str, Any]] = None
    config: Optional[Dict[str, Any]] = None


class PromptGenerateResponse(BaseModel):
    system_prompt: str


class AcceptanceEvaluateRequest(BaseModel):
    contract_id: Optional[str] = None
    contract_data: Optional[Dict[str, Any]] = None
    agent_output: str


class AcceptanceEvaluateResponse(BaseModel):
    evaluation_prompt: str


class InputValidateRequest(BaseModel):
    contract_id: Optional[str] = None
    contract_data: Optional[Dict[str, Any]] = None
    user_input: Dict[str, Any]


class InputValidateResponse(BaseModel):
    valid: bool
    errors: List[str] = []
    warnings: List[str] = []


# ── Predefined preset contracts ──

@router.get("/presets", response_model=List[ContractMetaItem])
async def list_preset_contracts(current_user: User = Depends(get_current_user)):
    """列出所有预置场景契约"""
    _ = current_user
    return list_preset_contracts_meta()


@router.get("/presets/{contract_id}")
async def get_preset_contract_detail(
    contract_id: str,
    current_user: User = Depends(get_current_user),
):
    """获取单个预置契约的完整内容"""
    _ = current_user
    contract = get_preset_contract(contract_id)
    if not contract:
        raise HTTPException(status_code=404, detail=f"预置契约不存在: {contract_id}")
    return {"id": contract_id, **contract}


# ── CRUD for user contracts ──

@router.get("/", response_model=List[ContractResponse])
async def list_contracts(
    category: Optional[str] = Query(None),
    is_public: Optional[bool] = Query(None),
    template_binding: Optional[str] = Query(None),
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """列出用户的场景契约"""
    query = db.query(SceneContract).filter(
        (SceneContract.user_id == current_user.id) | (SceneContract.is_public == 1)
    )
    if category:
        query = query.filter(SceneContract.category == category)
    if is_public is not None:
        query = query.filter(SceneContract.is_public == (1 if is_public else 0))
    if template_binding:
        query = query.filter(SceneContract.template_binding == template_binding)

    contracts = query.order_by(SceneContract.updated_at.desc()).all()
    return [c.to_dict() for c in contracts]


@router.post("/", response_model=ContractResponse, status_code=status.HTTP_201_CREATED)
async def create_contract(
    body: ContractCreate,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """创建自定义场景契约"""
    contract = SceneContract(
        id=str(uuid.uuid4()),
        name=body.name,
        description=body.description,
        goal=body.goal,
        role=body.role,
        input_description=body.input_description,
        input_schema=body.input_schema,
        constraints=body.constraints,
        forbidden_actions=body.forbidden_actions,
        required_tools=body.required_tools,
        deliverables=[d.model_dump() for d in body.deliverables],
        acceptance_criteria=body.acceptance_criteria,
        output_schema=body.output_schema,
        examples=[e.model_dump() for e in body.examples],
        category=body.category,
        tags=body.tags,
        is_public=1 if body.is_public else 0,
        template_binding=body.template_binding,
        user_id=current_user.id,
    )
    db.add(contract)
    db.commit()
    db.refresh(contract)
    return contract.to_dict()


@router.get("/{contract_id}", response_model=ContractResponse)
async def get_contract(
    contract_id: str,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """获取场景契约详情"""
    # 先查预置
    preset = get_preset_contract(contract_id)
    if preset:
        return {"id": contract_id, "version": 1, "is_public": 1, "use_count": 0,
                "user_id": None, "template_binding": None,
                "created_at": None, "updated_at": None, **preset}

    contract = db.query(SceneContract).filter(SceneContract.id == contract_id).first()
    if not contract:
        raise HTTPException(status_code=404, detail="契约不存在")
    if contract.user_id != current_user.id and contract.is_public == 0:
        raise HTTPException(status_code=403, detail="无权访问此契约")
    return contract.to_dict()


@router.put("/{contract_id}", response_model=ContractResponse)
async def update_contract(
    contract_id: str,
    body: ContractUpdate,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """更新场景契约"""
    contract = db.query(SceneContract).filter(SceneContract.id == contract_id).first()
    if not contract:
        raise HTTPException(status_code=404, detail="契约不存在")
    if contract.user_id != current_user.id:
        raise HTTPException(status_code=403, detail="只能修改自己的契约")

    update_data = body.model_dump(exclude_unset=True)
    # Handle list/dict fields
    for field in ["deliverables", "examples"]:
        if field in update_data and update_data[field] is not None:
            update_data[field] = [item if isinstance(item, dict) else item.model_dump()
                                  for item in update_data[field]]
    if "is_public" in update_data and update_data["is_public"] is not None:
        update_data["is_public"] = 1 if update_data["is_public"] else 0

    for key, value in update_data.items():
        if value is not None:
            setattr(contract, key, value)

    contract.version = (contract.version or 1) + 1
    db.commit()
    db.refresh(contract)
    return contract.to_dict()


@router.delete("/{contract_id}", status_code=status.HTTP_204_NO_CONTENT)
async def delete_contract(
    contract_id: str,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """删除场景契约"""
    contract = db.query(SceneContract).filter(SceneContract.id == contract_id).first()
    if not contract:
        raise HTTPException(status_code=404, detail="契约不存在")
    if contract.user_id != current_user.id:
        raise HTTPException(status_code=403, detail="只能删除自己的契约")
    db.delete(contract)
    db.commit()
    return Response(status_code=status.HTTP_204_NO_CONTENT)


# ── DSL 操作端点 ──

@router.post("/generate-prompt", response_model=PromptGenerateResponse)
async def generate_prompt_from_contract(
    body: PromptGenerateRequest,
    current_user: User = Depends(get_current_user),
):
    """从契约生成 system prompt"""
    _ = current_user

    # 获取契约数据
    contract_data = body.contract_data
    if not contract_data and body.contract_id:
        preset = get_preset_contract(body.contract_id)
        if preset:
            contract_data = preset
    if not contract_data:
        raise HTTPException(status_code=400, detail="请提供 contract_id 或 contract_data")

    config = ContractPromptConfig(**(body.config or {}))
    prompt = build_system_prompt_from_contract(contract_data, config)
    return {"system_prompt": prompt}


@router.post("/evaluate", response_model=AcceptanceEvaluateResponse)
async def evaluate_output_against_contract(
    body: AcceptanceEvaluateRequest,
    current_user: User = Depends(get_current_user),
):
    """生成验收评估 prompt（用于评估 Agent 输出是否满足契约）"""
    _ = current_user

    contract_data = body.contract_data
    if not contract_data and body.contract_id:
        preset = get_preset_contract(body.contract_id)
        if preset:
            contract_data = preset
    if not contract_data:
        raise HTTPException(status_code=400, detail="请提供 contract_id 或 contract_data")

    prompt = build_acceptance_prompt(contract_data, body.agent_output)
    return {"evaluation_prompt": prompt}


@router.post("/validate-input", response_model=InputValidateResponse)
async def validate_input_against_contract_endpoint(
    body: InputValidateRequest,
    current_user: User = Depends(get_current_user),
):
    """根据契约的 input_schema 验证用户输入"""
    _ = current_user

    contract_data = body.contract_data
    if not contract_data and body.contract_id:
        preset = get_preset_contract(body.contract_id)
        if preset:
            contract_data = preset
    if not contract_data:
        raise HTTPException(status_code=400, detail="请提供 contract_id 或 contract_data")

    result = validate_input_against_contract(contract_data, body.user_input)
    return result