Port Fly, Dig, Teleport and the Escape Rope

FLY opens _FlyMap in the party menu: the region's Town Map with "Where?",
the visited flypoints in turn and the Fly user's icon, then FlyScript flies
the icon off along SpriteAnimFunc_FlyFrom's path, enters the spawn point and
lands it with SpriteAnimFunc_FlyTo. Teleport returns to the last Pokémon
Center's town through IsSpawnPoint. Dig and the Escape Rope lead out of a
cave to the warp EnterMapWarp's SaveDigWarp recorded, which saves now keep.

newloadmap stops its script as StopScript does and the world resumes it on
the new map, which the landing and return movements need. A destination
that is not ported yet gives a notice.

Closes #25

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/game/scripts/start-menu.ts

@@ -13,6 +13,7 @@ import type { GameTime } from "../world/game-time";
 import { PartyEvolution, evoStoneCompatible } from "./evolution";
 import {
   copyScriptState,
+  type FieldMoveContext,
   type MartEntry,
   type ScriptEffect,
   type ScriptHost,
@@ -21,6 +22,8 @@ import {
 import { Pokegear } from "./pokegear";
 import { TrainerCard } from "./trainer-card";
 import { OptionsMenu, menuAccount } from "./options";
+import { flyMap } from "./fly-map";
+import { OW } from "../world/constants";
 import { readString, readText, type TextContext } from "./text";
 
 type Input = number | string | undefined;
@@ -86,19 +89,17 @@ export interface MenuCursors {
 
 /** The world's verdict on a field move chosen from the party menu: a
  * script to run once the menu closes (with the context the world checked),
- * the messages of a failed attempt, or a notice for what is not ported. */
+ * the messages of a failed attempt, a notice for what is not ported, or
+ * Fly's map to choose a destination from. */
 export type MenuFieldMove =
   | {
       script: number;
-      fieldMove: {
-        mon: number;
-        surfState?: number;
-        block?: { x: number; y: number; block: number };
-      };
+      fieldMove: FieldMoveContext;
       wild?: { species: number; level: number };
     }
   | { texts: number[] }
-  | { notice: string };
+  | { notice: string }
+  | { flyMap: true };
 
 /** What the start menu needs from the world. */
 export interface StartMenuHost {
@@ -114,6 +115,12 @@ export interface StartMenuHost {
   landmark(): number;
   /** A field move's checks for party slot `mon`, on the menu's draft. */
   fieldMove(state: ScriptState, mon: number, move: number): MenuFieldMove;
+  /** FlyFunction after the Fly map: flying to SPAWN_* point `spawn`. */
+  flyTo(state: ScriptState, mon: number, spawn: number): MenuFieldMove;
+  /** EscapeRopeFunction's checks, on the menu's draft. */
+  escapeRope(state: ScriptState): MenuFieldMove;
+  /** HasVisitedSpawn: the wVisitedSpawns bit of a SPAWN_* point. */
+  visitedSpawn(state: ScriptState, spawn: number): boolean;
   /** The script host a Pokégear phone call runs with. */
   scriptHost(): ScriptHost;
   /** GetWorldMapLocation for any map. */
@@ -512,14 +519,36 @@ export class StartMenuRun {
       yield* this.softboiledMilkDrink(slot);
       return false;
     }
-    const result = this.host.fieldMove(this.state, slot, move);
+    let result = this.host.fieldMove(this.state, slot, move);
+    if ("flyMap" in result) {
+      // FlyFunction.TryFly: B on the map (.illegal) returns to the party
+      // menu like a failure.
+      const spawn = yield* flyMap(
+        {
+          reader: this.reader,
+          text: () => this.text(),
+          landmark: () => {
+            const landmark = this.host.landmark();
+            const backup = this.state.backupWarp?.map;
+            return landmark === OW.LANDMARK_SPECIAL && backup
+              ? this.host.landmarkOf(backup)
+              : landmark;
+          },
+          visited: (spawn) => this.host.visitedSpawn(this.state, spawn),
+        },
+        this.state.party[slot].species,
+      );
+      if (spawn < 0) return false;
+      result = this.host.flyTo(this.state, slot, spawn);
+    }
     if ("script" in result) {
       this.deferred = result.script;
       this.deferredMove = result;
       return true;
     }
     if ("notice" in result) yield* this.notice(result.notice);
-    else for (const text of result.texts) yield* this.print(text);
+    else if ("texts" in result)
+      for (const text of result.texts) yield* this.print(text);
     return false;
   }
 
@@ -893,6 +922,21 @@ export class StartMenuRun {
         return yield* this.vitaminEffect(use);
       case MENU.EvoStoneEffect:
         return yield* this.evoStoneEffect(use);
+      case MENU.EscapeRopeEffect: {
+        // EscapeRopeEffect: UseDisposableItem once EscapeRopeOrDig queued
+        // its script; a failure prints nothing before Oak's message.
+        const result = this.host.escapeRope(this.state);
+        if ("notice" in result) {
+          yield* this.notice(result.notice);
+          return "unported";
+        }
+        if (!("script" in result)) return false;
+        this.useDisposableItem(use);
+        this.deferred = result.script;
+        this.deferredItem = item;
+        this.deferredMove = result;
+        return true;
+      }
       case MENU.BicycleEffect: {
         const script = this.host.bicycleScript(this.state, this.usingSelect);
         if (script === undefined) return false;