csv-parser: add _apply_mapping helper

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/services/llm_csv_parser.py

@@ -21,7 +21,7 @@ import csv
 import hashlib
 import io
 
-from app.services.csv_import import CSVImportError
+from app.services.csv_import import CSVImportError, ParsedPie, ParsedPosition
 
 # ---------------------------------------------------------------------------
 # Module-level constants
@@ -174,3 +174,80 @@ def _validate_mapping(
             raise LLMParseError(
                 f"LLM mapping cost_col={cost_col!r} maps to non-numeric value {cost_value!r}"
             )
+
+
+def _parse_number(value: str) -> float | None:
+    """Permissive float parse: strips thousands separators, currency
+    symbols, percent signs. Returns None on failure (so callers can
+    decide whether to skip or raise)."""
+    s = value.strip().replace(",", "").replace("$", "")
+    s = s.replace("€", "").replace("£", "").replace("%", "")
+    if not s:
+        return None
+    try:
+        return float(s)
+    except ValueError:
+        return None
+
+
+def _apply_mapping(
+    headers: list[str],
+    data_rows: list[list[str]],
+    mapping: dict,
+) -> ParsedPie:
+    """Iterate ``data_rows`` and produce a ``ParsedPie``.
+
+    Rows that lack a parseable quantity (blank, non-numeric, zero) are
+    silently skipped — broker exports often include summary or
+    placeholder rows after the position list. ``name_col`` falls back
+    to the ticker symbol when null."""
+    idx = {h: i for i, h in enumerate(headers)}
+    ticker_col = mapping["ticker_col"]
+    qty_col = mapping["qty_col"]
+    name_col = mapping.get("name_col")
+    cost_col = mapping.get("cost_col")
+
+    positions: list[ParsedPosition] = []
+    invested_total = 0.0
+    invested_seen = False
+
+    for row in data_rows:
+        if not any(c.strip() for c in row):
+            continue
+        ticker_raw = row[idx[ticker_col]] if idx[ticker_col] < len(row) else ""
+        ticker = ticker_raw.strip().upper()
+        if not ticker:
+            continue
+        qty_raw = row[idx[qty_col]] if idx[qty_col] < len(row) else ""
+        qty = _parse_number(qty_raw)
+        if qty is None or qty <= 0:
+            continue
+        avg_cost: float | None = None
+        if cost_col is not None and idx[cost_col] < len(row):
+            avg_cost = _parse_number(row[idx[cost_col]])
+        invested_value: float | None = None
+        if avg_cost is not None:
+            invested_value = qty * avg_cost
+            invested_total += invested_value
+            invested_seen = True
+        name = ""
+        if name_col is not None and idx[name_col] < len(row):
+            name = row[idx[name_col]].strip()
+        if not name:
+            name = ticker
+        positions.append(ParsedPosition(
+            slice=ticker,
+            name=name,
+            invested_value=invested_value,
+            current_value=None,
+            result=None,
+            quantity=qty,
+        ))
+
+    return ParsedPie(
+        name=None,
+        positions=tuple(positions),
+        invested=(invested_total if invested_seen else None),
+        value=None,
+        result=None,
+    )