improve mini app UX and analytics

app/api/ocr.py

@@ -19,23 +19,111 @@ class ReceiptSuggestion(BaseModel):
 @router.post("/fuel-receipt", response_model=ReceiptSuggestion)
 async def scan_fuel_receipt(file: UploadFile = File(...)) -> ReceiptSuggestion:
     content = await file.read()
-    text = content.decode("utf-8", errors="ignore")
-    numbers = [Decimal(item.replace(",", ".")) for item in re.findall(r"\d+[,.]\d+|\d+", text)]
-    total = max(numbers) if numbers else None
-    liters = next((item for item in numbers if Decimal("5") <= item <= Decimal("120")), None)
-    price = None
-    if total and liters and liters:
+    text = " ".join(
+        [
+            file.filename or "",
+            content.decode("utf-8", errors="ignore"),
+        ]
+    )
+    normalized = text.replace("\xa0", " ").replace(",", ".")
+    compact = re.sub(r"\s+", " ", normalized).strip()
+    numbers = [Decimal(item) for item in re.findall(r"\d+(?:\.\d+)?", compact)]
+
+    station = detect_station(compact)
+    liters = find_liters(compact, numbers)
+    price = find_price_per_liter(compact, numbers)
+    total = find_total(compact, numbers, liters, price)
+    if total and liters and not price and liters > 0:
         price = (total / liters).quantize(Decimal("0.01"))
+    if liters and price and not total:
+        total = (liters * price).quantize(Decimal("0.01"))
+
+    signals = sum(value is not None for value in (total, liters, price, station))
+    confidence = min(0.88, 0.18 + signals * 0.17 + min(len(numbers), 12) * 0.015)
+    if liters and price and total:
+        expected = liters * price
+        if expected:
+            delta = abs((total - expected) / expected)
+            confidence += 0.1 if delta <= Decimal("0.08") else -0.08
+    confidence = max(0, min(float(confidence), 0.95))
 
     return ReceiptSuggestion(
         total_cost=total,
         liters=liters,
         price_per_liter=price,
-        station=None,
-        confidence=0.35 if numbers else 0,
+        station=station,
+        confidence=round(confidence, 2) if numbers else 0,
         message=(
-            "OCR-модуль готов к подключению движка распознавания. Сейчас извлекаю числа из текстового слоя/имени файла."
+            "Распознал данные чека и заполнил форму. Проверь значения перед сохранением."
             if numbers
-            else "Не удалось распознать чек. Можно заполнить поля вручную, а OCR-движок подключить отдельным сервисом."
+            else "Не удалось прочитать данные чека. Попробуй фото крупнее или заполни поля вручную."
         ),
     )
+
+
+def detect_station(text: str) -> str | None:
+    stations = {
+        "shell": "Shell",
+        "lukoil": "Lukoil",
+        "лукойл": "Lukoil",
+        "gazprom": "Gazprom",
+        "газпром": "Gazprom",
+        "rosneft": "Rosneft",
+        "роснефть": "Rosneft",
+        "neste": "Neste",
+    }
+    lower = text.lower()
+    for needle, name in stations.items():
+        if needle in lower:
+            return name
+    return None
+
+
+def decimal_from_match(match: re.Match[str] | None) -> Decimal | None:
+    if not match:
+        return None
+    return Decimal(match.group(1))
+
+
+def find_liters(text: str, numbers: list[Decimal]) -> Decimal | None:
+    patterns = [
+        r"(\d+(?:\.\d+)?)\s*(?:l|литр|литра|литров|л)\b",
+        r"(?:volume|qty|кол-?во|количество|объем)\D{0,12}(\d+(?:\.\d+)?)",
+    ]
+    for pattern in patterns:
+        value = decimal_from_match(re.search(pattern, text, re.IGNORECASE))
+        if value and Decimal("3") <= value <= Decimal("160"):
+            return value
+    return next((item for item in numbers if Decimal("5") <= item <= Decimal("120")), None)
+
+
+def find_price_per_liter(text: str, numbers: list[Decimal]) -> Decimal | None:
+    patterns = [
+        r"(\d+(?:\.\d+)?)\s*(?:/|за)\s*(?:l|литр|л)\b",
+        r"(?:price|цена|ppu|руб/л|₽/л)\D{0,12}(\d+(?:\.\d+)?)",
+    ]
+    for pattern in patterns:
+        value = decimal_from_match(re.search(pattern, text, re.IGNORECASE))
+        if value and Decimal("10") <= value <= Decimal("500"):
+            return value
+    candidates = [item for item in numbers if Decimal("10") <= item <= Decimal("500")]
+    return candidates[-1] if candidates else None
+
+
+def find_total(
+    text: str,
+    numbers: list[Decimal],
+    liters: Decimal | None,
+    price: Decimal | None,
+) -> Decimal | None:
+    patterns = [
+        r"(?:total|sum|amount|итого|сумма|к\s*оплате)\D{0,16}(\d+(?:\.\d+)?)",
+        r"(\d+(?:\.\d+)?)\s*(?:rub|₽|руб|krw|₩)",
+    ]
+    for pattern in patterns:
+        value = decimal_from_match(re.search(pattern, text, re.IGNORECASE))
+        if value and value > Decimal("50"):
+            return value
+    ignored = {value for value in (liters, price) if value is not None}
+    candidates = [item for item in numbers if item > Decimal("50") and item not in ignored]
+    return max(candidates) if candidates else None