Multi-cabin search: --cabin economy,business (work-7ecx)

src/flight_cli/_multi_cabin.py

@@ -0,0 +1,121 @@
+"""Multi-cabin search orchestration: join N single-cabin SearchResults
+into rows with one price-per-cabin.
+
+The domain `Search` stays single-cabin — multi-cabin is an orchestration
+concept. The CLI fires N parallel single-cabin queries (one per requested
+cabin), then this module joins them on a stable per-itinerary key and
+produces rows the renderer can iterate.
+
+Join key: per-slice `(normalized first flight number, YYYY-MM-DD)` across
+all slices. Same shape as `pp.match.cash_match_key`, generalized to the
+whole itinerary so round-trips don't collide on outbound alone.
+"""
+
+from __future__ import annotations
+
+import re
+from dataclasses import dataclass, field
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from .domain import Cabin
+    from .models import Itinerary, SearchResult
+
+
+SliceKey = tuple[str, str]  # (FLIGHT_NUMBER_UPPER_NOSPACE, "YYYY-MM-DD")
+ItineraryKey = tuple[SliceKey, ...]
+
+_CASH_NUM_RE = re.compile(r"[\d,]*\d+(?:\.\d+)?")
+
+
+def _norm_fn(fn: str | None) -> str:
+    return (fn or "").upper().replace(" ", "")
+
+
+def _iso_date(s: str | None) -> str:
+    if not s:
+        return ""
+    return s.replace(" ", "T")[:10]
+
+
+def itinerary_key(itin: Itinerary) -> ItineraryKey | None:
+    """Per-slice (first-flight#, date) tuple across all slices of an
+    itinerary. None if any slice is missing both anchors — such itineraries
+    can't be safely joined and are skipped.
+    """
+    details = itin.itinerary
+    if not details or not details.slices:
+        return None
+    slice_keys: list[SliceKey] = []
+    for s in details.slices:
+        flights = s.flights or []
+        fn = _norm_fn(flights[0]) if flights else ""
+        dep = _iso_date(s.departure)
+        if not fn or not dep:
+            return None
+        slice_keys.append((fn, dep))
+    return tuple(slice_keys)
+
+
+def parse_price(s: str | None) -> float | None:
+    """Pull the first numeric value out of strings like 'USD530.00',
+    '$1,078', '1,078 USD'. Mirrors `pp.cli._parse_cash` — kept local to
+    avoid a cross-module dep just for one regex."""
+    if not s or s in ("—", "-"):
+        return None
+    m = _CASH_NUM_RE.search(s)
+    if not m:
+        return None
+    try:
+        return float(m.group(0).replace(",", ""))
+    except ValueError:
+        return None
+
+
+@dataclass
+class MultiCabinRow:
+    """One itinerary observed across one or more cabin queries.
+
+    `itinerary` is the first occurrence we saw (used for render: slices,
+    carriers, legroom). `prices` maps each cabin we have a price for to
+    its raw price string (e.g. 'USD623.00'). Cabins with no price are
+    absent from the dict — renderer treats absence as '—'.
+    """
+
+    itinerary: Itinerary
+    prices: dict[Cabin, str] = field(default_factory=dict)
+
+
+def merge(
+    results_by_cabin: dict[Cabin, SearchResult],
+    *,
+    sort_by: Cabin,
+    top_n: int,
+) -> list[MultiCabinRow]:
+    """Join itineraries across cabins. Sorted by `sort_by`'s parsed price
+    (asc); rows missing the sort cabin's price sink to the bottom. Truncated
+    to `top_n` rows.
+
+    Itineraries that can't be keyed (missing flight# or departure on any
+    slice) are skipped.
+    """
+    by_key: dict[ItineraryKey, MultiCabinRow] = {}
+    for cabin, res in results_by_cabin.items():
+        for it in res.solutions:
+            key = itinerary_key(it)
+            if key is None:
+                continue
+            row = by_key.get(key)
+            if row is None:
+                row = MultiCabinRow(itinerary=it)
+                by_key[key] = row
+            price = it.price
+            if price:
+                row.prices[cabin] = price
+
+    def sort_value(row: MultiCabinRow) -> float:
+        p = parse_price(row.prices.get(sort_by))
+        return p if p is not None else float("inf")
+
+    rows = sorted(by_key.values(), key=sort_value)
+    return rows[:top_n]