Add new feature to handle user input

backend/sentiment.py

@@ -0,0 +1,191 @@
+"""
+sentiment.py — Nieuws sentiment engine
+Bron: CryptoPanic API (gratis tier beschikbaar)
+Scoring: gewogen op votes + recency, -1.0 tot +1.0
+Geen zware ML modellen — rule-based op CryptoPanic's eigen
+bullish/bearish labels + vote ratio. Snel en betrouwbaar.
+"""
+import os
+import httpx
+import asyncio
+import logging
+from datetime import datetime, timedelta
+from dataclasses import dataclass, field
+
+logger = logging.getLogger(__name__)
+
+CRYPTOPANIC_BASE = "https://cryptopanic.com/api/v1"
+
+
+@dataclass
+class NewsItem:
+    title:       str
+    published:   datetime
+    source:      str
+    url:         str
+    currencies:  list[str]
+    sentiment:   str    # "positive" | "negative" | "neutral"
+    votes_pos:   int
+    votes_neg:   int
+    score:       float  # berekend gewogen score
+
+
+@dataclass
+class SentimentResult:
+    symbol:        str           # bijv. "BTC"
+    score:         float         # -1.0 tot +1.0
+    label:         str           # "positief" | "negatief" | "neutraal"
+    confidence:    float         # 0.0 tot 1.0
+    news_count:    int
+    recent_news:   list[NewsItem] = field(default_factory=list)
+    last_updated:  datetime = field(default_factory=datetime.utcnow)
+
+
+def _calculate_item_score(item: dict) -> float:
+    """
+    Bereken score per nieuwsitem op basis van:
+    - CryptoPanic kind label (bullish/bearish)
+    - Vote verhouding
+    - Recency (items ouder dan 12u wegen minder)
+    """
+    votes   = item.get("votes", {})
+    pos     = votes.get("positive", 0)
+    neg     = votes.get("negative", 0)
+    total   = pos + neg
+
+    # Vote-gebaseerde score
+    if total > 0:
+        vote_score = (pos - neg) / total  # -1 tot +1
+    else:
+        vote_score = 0.0
+
+    # CryptoPanic kind label
+    kind = item.get("kind", "news")
+    if kind == "bullish":
+        label_score = 0.6
+    elif kind == "bearish":
+        label_score = -0.6
+    else:
+        label_score = 0.0
+
+    # Recency weight
+    try:
+        published = datetime.fromisoformat(
+            item["published_at"].replace("Z", "+00:00")
+        ).replace(tzinfo=None)
+        age_hours = (datetime.utcnow() - published).total_seconds() / 3600
+        recency   = max(0.2, 1.0 - (age_hours / 24))  # 24u = 0.2 gewicht
+    except Exception:
+        recency = 0.5
+
+    # Gewogen combinatie
+    score = (vote_score * 0.4 + label_score * 0.6) * recency
+    return round(score, 3)
+
+
+async def fetch_sentiment(symbol: str) -> SentimentResult:
+    """
+    Haal sentiment op voor een specifiek crypto symbol.
+    symbol = coin code zonder /EUR, bijv. "BTC", "ETH"
+    """
+    api_key = os.getenv("CRYPTOPANIC_API_KEY", "")
+
+    if not api_key:
+        logger.warning("CRYPTOPANIC_API_KEY niet ingesteld — dummy sentiment")
+        return _dummy_sentiment(symbol)
+
+    url    = f"{CRYPTOPANIC_BASE}/posts/"
+    params = {
+        "auth_token":  api_key,
+        "currencies":  symbol,
+        "filter":      "hot",
+        "public":      "true",
+    }
+
+    try:
+        async with httpx.AsyncClient(timeout=10) as client:
+            resp = await client.get(url, params=params)
+            resp.raise_for_status()
+            data = resp.json()
+
+        results   = data.get("results", [])
+        news_items = []
+        scores     = []
+
+        for item in results[:20]:  # Maximaal 20 recente items
+            item_score = _calculate_item_score(item)
+            scores.append(item_score)
+
+            currencies = [
+                c.get("code", "") for c in item.get("currencies", [])
+            ]
+
+            votes = item.get("votes", {})
+            news_items.append(NewsItem(
+                title=item.get("title", ""),
+                published=datetime.fromisoformat(
+                    item["published_at"].replace("Z", "+00:00")
+                ).replace(tzinfo=None),
+                source=item.get("source", {}).get("title", ""),
+                url=item.get("url", ""),
+                currencies=currencies,
+                sentiment="positive" if item_score > 0.1 else (
+                    "negative" if item_score < -0.1 else "neutral"
+                ),
+                votes_pos=votes.get("positive", 0),
+                votes_neg=votes.get("negative", 0),
+                score=item_score,
+            ))
+
+        if not scores:
+            return _dummy_sentiment(symbol)
+
+        avg_score   = sum(scores) / len(scores)
+        confidence  = min(1.0, len(scores) / 10)  # 10+ items = max confidence
+
+        if avg_score > 0.15:
+            label = "positief"
+        elif avg_score < -0.15:
+            label = "negatief"
+        else:
+            label = "neutraal"
+
+        return SentimentResult(
+            symbol=symbol,
+            score=round(avg_score, 3),
+            label=label,
+            confidence=round(confidence, 2),
+            news_count=len(scores),
+            recent_news=news_items[:5],  # Top 5 voor dashboard
+        )
+
+    except Exception as e:
+        logger.error(f"Sentiment fetch mislukt voor {symbol}: {e}")
+        return _dummy_sentiment(symbol)
+
+
+def _dummy_sentiment(symbol: str) -> SentimentResult:
+    """Fallback als API niet beschikbaar is."""
+    return SentimentResult(
+        symbol=symbol,
+        score=0.0,
+        label="neutraal",
+        confidence=0.0,
+        news_count=0,
+        recent_news=[],
+    )
+
+
+async def fetch_all_sentiments(symbols: list[str]) -> dict[str, SentimentResult]:
+    """Haal sentiment op voor meerdere coins parallel."""
+    tasks   = [fetch_sentiment(s) for s in symbols]
+    results = await asyncio.gather(*tasks, return_exceptions=True)
+
+    output = {}
+    for symbol, result in zip(symbols, results):
+        if isinstance(result, SentimentResult):
+            output[symbol] = result
+        else:
+            output[symbol] = _dummy_sentiment(symbol)
+
+    return output