Handle indexed PSCR rate book sections

Author: javaDevJT

custom_components/dte_rates/pscr_parser.py

@@ -19,34 +19,38 @@ def parse_pscr_rates_from_pdf(pdf_bytes: bytes) -> dict[str, Decimal]:
     text = "\n".join(page.extract_text() or "" for page in reader.pages)
     lines = [re.sub(r"\s+", " ", line).strip() for line in text.splitlines()]
 
-    section = _power_supply_surcharge_lines(lines)
     rates: dict[str, Decimal] = {}
-    for line in section:
-        match = _RATE_ROW_RE.match(line)
-        if match:
-            rates[match.group("code").upper()] = Decimal(match.group("pscr"))
+    for section in _power_supply_surcharge_sections(lines):
+        for line in section:
+            match = _RATE_ROW_RE.match(line)
+            if match:
+                rates[match.group("code").upper()] = Decimal(match.group("pscr"))
+        if rates:
+            break
 
     if not rates:
         raise ValueError("MPSC DTE rate book does not contain PSCR tariff rows")
     return rates
 
 
-def _power_supply_surcharge_lines(lines: list[str]) -> list[str]:
-    start = None
+def _power_supply_surcharge_sections(lines: list[str]) -> list[list[str]]:
+    sections: list[list[str]] = []
     for idx, line in enumerate(lines):
         lower = line.lower()
         if "c8.5 surcharges and credits applicable to power supply service" in lower:
-            start = idx
-            break
+            end = _next_delivery_surcharge_index(lines, idx + 1)
+            sections.append(lines[idx:end])
 
-    if start is None:
-        return lines
+    if not sections:
+        sections.append(lines)
+    return sections
 
+
+def _next_delivery_surcharge_index(lines: list[str], start: int) -> int:
     end = len(lines)
-    for idx in range(start + 1, len(lines)):
+    for idx in range(start, len(lines)):
         lower = lines[idx].lower()
         if "c9 surcharges and credits applicable to delivery service" in lower:
             end = idx
             break
-
-    return lines[start:end]
+    return end

docs/research/rider18-export-rates.md

@@ -40,6 +40,8 @@ For net metering, keep the existing behavior: export uses the full active import
 
 The setup flow reports how many MPSC tariff PSCR factors were loaded. Export entities expose the selected rate's PSCR value, the PSCR source URL, and the full parsed `pscr_rates` map.
 
+The MPSC rate book can mention `C8.5 Surcharges and Credits Applicable to Power Supply Service` in the front-matter index before the real tariff table. Parser logic must scan candidate C8.5 sections until it finds tariff rows, otherwise it can stop at the index, see no PSCR rows, and incorrectly log that the rate book does not contain PSCR tariff rows.
+
 Export entities expose whether the active period has enough data for the full formula:
 
 - `export_rate_source: rider18_formula` when generation components and PSCR are present.

tests/test_pscr_parser.py

@@ -6,6 +6,10 @@
 
 
 SAMPLE_RATE_BOOK_TEXT = """
+C8 SURCHARGES AND CREDITS APPLICABLE TO POWER SUPPLY SERVICE
+C8.5 Surcharges and Credits Applicable to Power Supply Service C-65.00
+C9 SURCHARGES AND CREDITS APPLICABLE TO DELIVERY SERVICE
+C9.1 Nuclear Surcharge C-66.00
 C8.5 SURCHARGES AND CREDITS APPLICABLE TO POWER SUPPLY SERVICE
 Rate Schedule Description PSCR Factor Other Charges
 D1 Non Transmitting Meter 1.877 0.0222 0.2305 2.1297