"""
Supplier API Handler (只读)

职责：
- 加载供应商列表
- 不支持创建/更新/删除
"""

from typing import List, Dict
from ...datasource.api.handler import BaseApiHandler
from ...datasource.task_result import TaskResult
from ...common.sync_node import SyncNode
from .sync_node import SupplierSyncNode
from schemas.supplier.supplier import SupplierDetailResponse


class SupplierApiHandler(BaseApiHandler):
    """供应商 API Handler (只读)"""
    
    def __init__(self, load_mode: str = "api", max_total: int | None = None):
        super().__init__(node_class=SupplierSyncNode, schema=SupplierDetailResponse)
        self._load_mode = load_mode
        self._max_total = max_total
    
    async def load(self) -> List[SyncNode]:
        """加载供应商列表（支持分页）"""
        try:
            if self._load_mode == "persisted_only":
                existing_count = 0
                if self._collection is not None:
                    existing_count = len(self._collection.filter(node_type=self.node_type))
                print(f"ℹ️ Supplier load skipped (persisted_only). Existing={existing_count}")
                return []

            nodes = []
            page = 1
            page_size = 10000
            
            while True:
                # 获取一页数据
                suppliers, total = await api_get_supplier_list(
                    self.api_client,
                    page=page,
                    page_size=page_size
                )
                
                # 没有数据了，退出循环
                if not suppliers:
                    break
                
                # 转换为节点
                for supplier_model in suppliers:
                    supplier_data = supplier_model.model_dump()
                    nodes.append(self._create_node(supplier_data))

                    if self._max_total is not None and len(nodes) >= self._max_total:
                        return nodes
                
                # 检查是否还有下一页
                if total > 0 and page * page_size >= total:
                    break
                
                # 如果没有total字段，且items数量小于page_size，说明是最后一页
                if total == 0 and len(suppliers) < page_size:
                    break
                
                page += 1
            
            return nodes
        except Exception as e:
            print(f"❌ Failed to load suppliers: {e}")
            return []
    
    async def create_all(self, nodes: List[SyncNode]) -> List[TaskResult]:
        """不支持创建"""
        return [
            TaskResult.failed(node_id=node.node_id, error="Supplier creation not supported")
            for node in nodes
        ]
    
    async def update_all(self, nodes: List[SyncNode]) -> List[TaskResult]:
        """不支持更新"""
        return [
            TaskResult.failed(node_id=node.node_id, error="Supplier update not supported")
            for node in nodes
        ]
    
    async def delete_all(self, nodes: List[SyncNode]) -> List[TaskResult]:
        """不支持删除"""
        return [
            TaskResult.failed(node_id=node.node_id, error="Supplier deletion not supported")
            for node in nodes
        ]
    
    async def poll_tasks(self, task_ids: List[str]) -> Dict[str, TaskResult]:
        """轮询异步任务状态（占位）"""
        return await super().poll_tasks(task_ids)
    
# ========== 静态 API 函数 ==========

async def api_get_supplier_list(client, page: int = 1, page_size: int = 100) -> tuple[List[SupplierDetailResponse], int]:
    """
    获取供应商列表 GET /supplier/list
    
    Args:
        client: API客户端
        page: 页码，从1开始
        page_size: 每页大小
        
    Returns:
        tuple[List[SupplierDetailResponse], int]: (验证过的供应商列表, 总数)
    """
    from pydantic import ValidationError
    
    response = await client.request(
        method="GET",
        endpoint="/supplier/list",
        params={"page": page, "page_size": page_size}
    )
    if response.get("code") != 200:
        raise Exception(f"API error: {response.get('message', 'Unknown error')}")
    
    # 注意：supplier返回格式可能是 {code: 200, list: [...]} 或 {code: 200, data: {list: [...]}}
    data = response.get("data", {})
    items = data.get("list", []) if data else response.get("list", [])
    total = data.get("total", 0) if data else response.get("total", 0)
    
    # 验证每个返回项
    validated_items = []
    for item in items:
        try:
            validated_item = SupplierDetailResponse.model_validate(item)
            validated_items.append(validated_item)
        except ValidationError as e:
            print(f"⚠️ Skipping invalid supplier item: {e}")
            continue
    
    return validated_items, total