"""CSV feed adapter.

Reads a supplier CSV with columns:
    sku,title,cost,inventory,shipping_cost,shipping_time,category,image_url
    (optional: description, brand)
`data_or_url` is either raw CSV text or an http(s) URL to fetch.
"""
import csv
import io
import urllib.request

from app.engines.suppliers.base import SupplierAdapter, register_adapter


@register_adapter
class CSVAdapter(SupplierAdapter):
    adapter_type = "csv"

    def __init__(self, supplier, data_or_url=""):
        super().__init__(supplier, data_or_url=data_or_url)
        self._rows = None

    def _load(self):
        if self._rows is not None:
            return
        src = (self.data_or_url or "").strip()
        if src.startswith(("http://", "https://")):
            with urllib.request.urlopen(src, timeout=30) as resp:
                src = resp.read().decode("utf-8", "replace")
        self._rows = list(csv.DictReader(io.StringIO(src)))

    def get_products(self):
        self._load()
        products = []
        for row in self._rows:
            sku = (row.get("sku") or "").strip()
            title = (row.get("title") or "").strip()
            if not sku or not title:
                continue
            products.append(
                {
                    "sku": sku,
                    "title": title,
                    "description": (row.get("description") or "").strip() or None,
                    "category": (row.get("category") or "").strip() or None,
                    "brand": (row.get("brand") or "").strip() or None,
                    "cost": float(row.get("cost") or 0),
                    "inventory": int(float(row.get("inventory") or 0)),
                    "shipping_cost": float(row.get("shipping_cost") or 0),
                    "shipping_time": (row.get("shipping_time") or "").strip() or "3-5 days",
                    "image_url": (row.get("image_url") or "").strip() or None,
                }
            )
        return products

    def get_inventory(self):
        return [
            {"supplier_sku": p["sku"], "inventory": p["inventory"]}
            for p in self.get_products()
        ]

    def get_price(self, sku):
        for p in self.get_products():
            if p["sku"] == sku:
                return p["cost"]
        return None

    def create_order(self, items):
        return {"adapter": "csv", "ref": f"csv:{len(items)}:items", "items": items}

    def get_order_status(self, ref):
        return "confirmed"

    def get_tracking(self, ref):
        return None

    def cancel_order(self, ref):
        return {"ref": ref, "status": "cancelled"}