feat(phase-4-plus): project save/load persists Tower offset + Phase 7+/12d state

src/ropeway/project.py

@@ -32,6 +32,7 @@
 from pathlib import Path
 
 from .alignment import Alignment, Tower
+from .obstacles import ForcedFlyOverZone, NoTowerZone, ZoneKind
 from .safety import ConstraintConfig
 
 DEFAULT_DB_PATH = Path("data/projects.db")
@@ -46,11 +47,62 @@
     corridor_len REAL,
     utm_epsg     INTEGER,
     config_json  TEXT NOT NULL,
-    towers_json  TEXT NOT NULL
+    towers_json  TEXT NOT NULL,
+    extras_json  TEXT NOT NULL DEFAULT '{}'
 );
 """
 
 
+def _zones_to_json(zones: list) -> list[dict]:
+    """Serialise a list of NoTowerZone instances (Phase 7+)."""
+    out = []
+    for z in zones or []:
+        out.append({
+            "distance_start_m": z.distance_start_m,
+            "distance_end_m": z.distance_end_m,
+            "kind": z.kind.value if hasattr(z.kind, "value") else str(z.kind),
+            "name": z.name,
+        })
+    return out
+
+
+def _zones_from_json(rows: list[dict]) -> list[NoTowerZone]:
+    return [
+        NoTowerZone(
+            distance_start_m=float(r["distance_start_m"]),
+            distance_end_m=float(r["distance_end_m"]),
+            kind=ZoneKind(r["kind"]) if r.get("kind") else ZoneKind.PROTECTED,
+            name=str(r.get("name", "")),
+        )
+        for r in (rows or [])
+    ]
+
+
+def _flyovers_to_json(zones: list) -> list[dict]:
+    """Serialise a list of ForcedFlyOverZone instances (Phase 12d)."""
+    out = []
+    for z in zones or []:
+        out.append({
+            "distance_start_m": z.distance_start_m,
+            "distance_end_m": z.distance_end_m,
+            "min_cable_elev_m": z.min_cable_elev_m,
+            "name": z.name,
+        })
+    return out
+
+
+def _flyovers_from_json(rows: list[dict]) -> list[ForcedFlyOverZone]:
+    return [
+        ForcedFlyOverZone(
+            distance_start_m=float(r["distance_start_m"]),
+            distance_end_m=float(r["distance_end_m"]),
+            min_cable_elev_m=float(r["min_cable_elev_m"]),
+            name=str(r.get("name", "")),
+        )
+        for r in (rows or [])
+    ]
+
+
 @dataclass
 class ProjectRecord:
     id: int
@@ -62,14 +114,39 @@ class ProjectRecord:
     utm_epsg: int
     config: ConstraintConfig
     towers: list[Tower]
+    # Phase 4+ — Phase 7+ / 12d state persisted alongside the towers.
+    intermediate_stations: list[float] = None
+    no_tower_zones: list = None
+    forced_flyover_zones: list = None
 
-    def to_alignment(self, profile_fn, clearance_profile=None) -> Alignment:
-        """Rebuild a runnable Alignment given a freshly-sampled profile_fn."""
+    def __post_init__(self) -> None:
+        if self.intermediate_stations is None:
+            self.intermediate_stations = []
+        if self.no_tower_zones is None:
+            self.no_tower_zones = []
+        if self.forced_flyover_zones is None:
+            self.forced_flyover_zones = []
+
+    def to_alignment(self, profile_fn, clearance_profile=None,
+                     surface_fn=None) -> Alignment:
+        """Rebuild a runnable Alignment given a freshly-sampled profile_fn.
+
+        Phase 4+: ``Tower.offset`` and ``is_station`` are now preserved,
+        and the Phase 7+ / 12d corridor constraints carry through so the
+        round-tripped alignment evaluates identically to the saved one.
+        """
         return Alignment(
-            towers=[Tower(t.distance, t.height) for t in self.towers],
+            towers=[
+                Tower(t.distance, t.height,
+                      is_station=bool(t.is_station), offset=float(t.offset))
+                for t in self.towers
+            ],
             profile_fn=profile_fn,
             cfg=self.config,
             clearance_profile=clearance_profile,
+            no_tower_zones=list(self.no_tower_zones),
+            surface_fn=surface_fn,
+            forced_flyover_zones=list(self.forced_flyover_zones),
         )
 
 
@@ -78,6 +155,14 @@ def _connect(db_path: str | Path) -> sqlite3.Connection:
     db_path.parent.mkdir(parents=True, exist_ok=True)
     conn = sqlite3.connect(str(db_path))
     conn.execute(_SCHEMA)
+    # Phase 4+ schema migration: older DBs predate the extras_json column;
+    # add it idempotently so an upgraded process can still read old files.
+    try:
+        conn.execute("ALTER TABLE projects ADD COLUMN extras_json TEXT NOT NULL DEFAULT '{}'")
+        conn.commit()
+    except sqlite3.OperationalError:
+        # Column already exists — expected on every run after the first.
+        pass
     return conn
 
 
@@ -90,28 +175,47 @@ def save_project(
     corridor_len: float,
     utm_epsg: int,
     db_path: str | Path = DEFAULT_DB_PATH,
+    intermediate_stations: list[float] | None = None,
 ) -> int:
-    """Persist a project and return its new row id."""
+    """Persist a project and return its new row id.
+
+    Phase 4+: Tower offset + is_station are now stored, and Phase 7+ /
+    12d corridor constraints (no_tower_zones, intermediate_stations,
+    forced_flyover_zones) are serialised alongside as ``extras_json``.
+    """
     conn = _connect(db_path)
     try:
         config_json = json.dumps(asdict(alignment.cfg))
-        towers_json = json.dumps(
-            [{"distance": t.distance, "height": t.height} for t in alignment.towers]
-        )
+        towers_json = json.dumps([
+            {
+                "distance": t.distance,
+                "height": t.height,
+                "is_station": bool(t.is_station),
+                "offset": float(t.offset),
+            }
+            for t in alignment.towers
+        ])
+        extras_json = json.dumps({
+            "intermediate_stations": list(intermediate_stations or []),
+            "no_tower_zones": _zones_to_json(alignment.no_tower_zones),
+            "forced_flyover_zones": _flyovers_to_json(
+                alignment.forced_flyover_zones
+            ),
+        })
         cur = conn.execute(
             """
             INSERT INTO projects
                 (name, created_at, start_lon, start_lat, end_lon, end_lat,
-                 corridor_len, utm_epsg, config_json, towers_json)
-            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+                 corridor_len, utm_epsg, config_json, towers_json, extras_json)
+            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
             """,
             (
                 name,
                 datetime.now(timezone.utc).isoformat(timespec="seconds"),
                 start_lonlat[0], start_lonlat[1],
                 end_lonlat[0], end_lonlat[1],
                 corridor_len, utm_epsg,
-                config_json, towers_json,
+                config_json, towers_json, extras_json,
             ),
         )
         conn.commit()
@@ -138,13 +242,19 @@ def list_projects(db_path: str | Path = DEFAULT_DB_PATH) -> list[dict]:
 
 
 def load_project(project_id: int, db_path: str | Path = DEFAULT_DB_PATH) -> ProjectRecord:
-    """Load a project by id. Raises KeyError if not found."""
+    """Load a project by id. Raises KeyError if not found.
+
+    Phase 4+: rehydrates Tower offset + is_station and the corridor-
+    constraint extras saved alongside the towers; pre-4+ records (no
+    extras column populated) deserialise to empty zone/station lists
+    so legacy callers see no behavioural change.
+    """
     conn = _connect(db_path)
     try:
         row = conn.execute(
             """
             SELECT id, name, created_at, start_lon, start_lat, end_lon, end_lat,
-                   corridor_len, utm_epsg, config_json, towers_json
+                   corridor_len, utm_epsg, config_json, towers_json, extras_json
             FROM projects WHERE id = ?
             """,
             (project_id,),
@@ -153,7 +263,15 @@ def load_project(project_id: int, db_path: str | Path = DEFAULT_DB_PATH) -> Proj
             raise KeyError(f"project id {project_id} not found in {db_path}")
         cfg_dict = json.loads(row[9])
         config = ConstraintConfig(**cfg_dict)
-        towers = [Tower(t["distance"], t["height"]) for t in json.loads(row[10])]
+        towers = [
+            Tower(
+                t["distance"], t["height"],
+                is_station=bool(t.get("is_station", False)),
+                offset=float(t.get("offset", 0.0)),
+            )
+            for t in json.loads(row[10])
+        ]
+        extras = json.loads(row[11] or "{}")
         return ProjectRecord(
             id=row[0],
             name=row[1],
@@ -164,6 +282,11 @@ def load_project(project_id: int, db_path: str | Path = DEFAULT_DB_PATH) -> Proj
             utm_epsg=row[8],
             config=config,
             towers=towers,
+            intermediate_stations=list(extras.get("intermediate_stations", [])),
+            no_tower_zones=_zones_from_json(extras.get("no_tower_zones", [])),
+            forced_flyover_zones=_flyovers_from_json(
+                extras.get("forced_flyover_zones", [])
+            ),
         )
     finally:
         conn.close()