Add IsThereAnyDeal as a deal source alongside CheapShark

Users can now choose between CheapShark, ITAD, or both via the
DEAL_SOURCES env var (comma-separated, default: "cheapshark"). When
"itad" is included, the bot polls GET /deals/v2 for current deals with
discount/price filtering and posts them with the same formatting style.
ITAD deals include built-in historical low detection via the API's
deal flags. Preflight checks enforce ITAD_API_KEY when ITAD is a
configured deal source.

https://claude.ai/code/session_01B7YPGrE3NatkwadCXVjv2j

gaming_deals_bot/itad_deals.py

@@ -0,0 +1,126 @@
+"""IsThereAnyDeal deals list — fetch current deals from the ITAD API."""
+
+import logging
+from dataclasses import dataclass
+
+import httpx
+
+from .itad import BASE_URL
+
+logger = logging.getLogger(__name__)
+
+# ITAD shop ID for Steam
+STEAM_SHOP_ID = 61
+
+
+@dataclass
+class ITADDeal:
+    game_id: str  # ITAD UUID
+    slug: str
+    title: str
+    sale_price: float  # current deal price
+    normal_price: float  # regular (non-sale) price
+    discount: int  # percentage off (0-100)
+    currency: str
+    shop_name: str
+    shop_id: int
+    url: str  # purchase redirect URL
+    is_historical_low: bool
+    timestamp: str  # ISO datetime of deal
+    expiry: str | None  # ISO datetime when deal expires
+
+    @property
+    def dedup_id(self) -> str:
+        return f"itad-{self.game_id}-{self.shop_id}-{self.discount}"
+
+    @property
+    def sale_price_usd(self) -> str:
+        return f"{self.sale_price:.2f}"
+
+    @property
+    def normal_price_usd(self) -> str:
+        return f"{self.normal_price:.2f}"
+
+
+async def fetch_deals(
+    client: httpx.AsyncClient,
+    api_key: str,
+    *,
+    max_price: float = 20,
+    min_discount: float = 50,
+    limit: int = 20,
+) -> list[ITADDeal]:
+    """Fetch current deals from IsThereAnyDeal.
+
+    Uses GET /deals/v2 with sorting by highest discount.
+    """
+    if not api_key:
+        return []
+
+    params: dict = {
+        "key": api_key,
+        "sort": "-cut",
+        "limit": min(limit, 200),
+        "nondeals": "false",
+    }
+
+    try:
+        resp = await client.get(f"{BASE_URL}/deals/v2", params=params)
+        resp.raise_for_status()
+        data = resp.json()
+    except (httpx.HTTPError, ValueError) as exc:
+        logger.error("ITAD deals API error: %s", exc)
+        return []
+
+    raw_list = data.get("list", [])
+    logger.info("ITAD returned %d raw deals (before filtering)", len(raw_list))
+
+    deals: list[ITADDeal] = []
+    for entry in raw_list:
+        deal_data = entry.get("deal", {})
+        if not deal_data:
+            continue
+
+        cut = deal_data.get("cut", 0)
+        price_amount = deal_data.get("price", {}).get("amount", 0)
+        regular_amount = deal_data.get("regular", {}).get("amount", 0)
+        currency = deal_data.get("price", {}).get("currency", "USD")
+        title = entry.get("title", "?")
+
+        # Apply filters
+        if cut < min_discount:
+            logger.debug(
+                "Filtered out %s: discount %d%% < %d%%", title, cut, int(min_discount)
+            )
+            continue
+        if price_amount > max_price:
+            logger.debug(
+                "Filtered out %s: price %.2f > %.2f", title, price_amount, max_price
+            )
+            continue
+
+        flag = deal_data.get("flag")
+        is_historical_low = flag in ("H", "N")
+
+        shop = deal_data.get("shop", {})
+
+        deals.append(
+            ITADDeal(
+                game_id=entry.get("id", ""),
+                slug=entry.get("slug", ""),
+                title=title,
+                sale_price=price_amount,
+                normal_price=regular_amount,
+                discount=cut,
+                currency=currency,
+                shop_name=shop.get("name", "Unknown"),
+                shop_id=shop.get("id", 0),
+                url=deal_data.get("url", ""),
+                is_historical_low=is_historical_low,
+                timestamp=deal_data.get("timestamp", ""),
+                expiry=deal_data.get("expiry"),
+            )
+        )
+
+    logger.info("ITAD returned %d deals after filtering", len(deals))
+    return deals