Add native Crystal exploration port and reference tooling

2026-09-23 09:23:29 +02:00
1 parent 2127f5f459
commit 8b80d05ca2
@@ -0,0 +1,370 @@
+import { CrystalAssets } from "../rom/assets";
+import { INITIAL_POSITION, NATIVE_MAPS, SYMBOLS } from "../rom/profile";
+import {
+  runScript,
+  type ScriptResult,
+  type ScriptState,
+} from "../scripts/interpreter";
+import {
+  DIRECTION_ORDER,
+  VECTORS,
+  type Direction,
+  type MapObject,
+} from "./types";
+
+export interface NativeSave {
+  format: "crystal-native";
+  version: 1;
+  map: string;
+  x: number;
+  y: number;
+  direction: Direction;
+  name: string;
+  avatar: "chris" | "kris";
+  tilesWalked: number;
+  events: number[];
+  flags: number[];
+  variables: Record<number, number>;
+}
+
+/** Deterministic native world rules. Rendering, browser APIs and emulator
+ * registers are deliberately absent; callers provide time and input. */
+export class GameWorld {
+  mapId: string = INITIAL_POSITION.map;
+  x: number = INITIAL_POSITION.x;
+  y: number = INITIAL_POSITION.y;
+  direction: Direction = "down";
+  name = "CHRIS";
+  avatar: "chris" | "kris" = "chris";
+  tilesWalked = 0;
+  state: ScriptState = { events: new Set(), flags: new Set(), variables: {} };
+  dialogue:
+    { pages: string[]; index: number; result: ScriptResult } | undefined;
+  notice = "";
+  diagnostic = "";
+  private objectDirections = new Map<number, Direction>();
+
+  constructor(
+    readonly assets: CrystalAssets,
+    private now: () => Date = () => new Date(),
+  ) {
+    // Port the original initialization event table through the script engine;
+    // this supplies NPC visibility flags without distributing a copied table.
+    const initial = assets.reader.far(SYMBOLS.standardScripts + 24 * 3);
+    this.state = runScript(assets.reader, initial, this.state, this.name);
+    assets.map(this.mapId);
+  }
+  get map() {
+    return this.assets.map(this.mapId);
+  }
+  get timeOfDay(): number {
+    const mode = this.map.paletteMode;
+    if (mode === 1) return 1;
+    if (mode === 2) return 2;
+    if (mode === 3) return 0;
+    if (mode === 4) return 3;
+    const hour = this.now().getHours();
+    return hour >= 4 && hour < 10 ? 0 : hour >= 10 && hour < 18 ? 1 : 2;
+  }
+  objects(): MapObject[] {
+    const hour = this.now().getHours(),
+      timeMask = 1 << this.timeOfDay;
+    return this.map.objects.filter((object) => {
+      if (
+        object.eventFlag !== 0xffff &&
+        this.state.events.has(object.eventFlag)
+      )
+        return false;
+      if (!this.assets.sprite(object.sprite)) return false;
+      if (object.hour1 === 0xff)
+        return object.hour2 === 0xff || Boolean(object.hour2 & timeMask);
+      if (object.hour1 === object.hour2) return true;
+      return object.hour1 < object.hour2
+        ? hour >= object.hour1 && hour < object.hour2
+        : hour >= object.hour1 || hour < object.hour2;
+    });
+  }
+  objectDirection(object: MapObject): Direction {
+    return (
+      this.objectDirections.get(object.id) ??
+      DIRECTION_ORDER[object.movement - 6] ??
+      "down"
+    );
+  }
+  private clearNotice() {
+    this.notice = "";
+    this.diagnostic = "";
+  }
+  private canStand(x: number, y: number): boolean {
+    if (x < 0 || y < 0 || x >= this.map.width || y >= this.map.height)
+      return false;
+    if (this.assets.permission(this.assets.collision(this.map, x, y)) !== 0)
+      return false;
+    return !this.objects().some((object) => object.x === x && object.y === y);
+  }
+
+  move(direction: Direction): boolean {
+    if (this.dialogue) return false;
+    this.clearNotice();
+    this.direction = direction;
+    const [dx, dy] = VECTORS[direction],
+      x = this.x + dx,
+      y = this.y + dy;
+    if (x < 0 || y < 0 || x >= this.map.width || y >= this.map.height) {
+      if (
+        this.map.connections.some(
+          (connection) => connection.direction === direction,
+        )
+      )
+        this.notice = "Routes beyond New Bark Town are not ported yet.";
+      return false;
+    }
+    const collision = this.assets.collision(this.map, x, y);
+    // Forced movement, surfing and ledges need their own translated rules.
+    // Refuse them rather than treating a land permission as ordinary walking.
+    if ([0x30, 0x40, 0x50, 0x60, 0xa0].includes(collision & 0xf0)) {
+      this.notice = "This movement type is not ported yet.";
+      return false;
+    }
+    if (!this.canStand(x, y)) return false;
+    // Directional edge walls: up/down/left/right encoded as hardware direction IDs.
+    const edges: Record<number, Direction[]> = {
+      0xb0: ["right"],
+      0xb1: ["left"],
+      0xb2: ["up"],
+      0xb3: ["down"],
+      0xb4: ["down", "right"],
+      0xb5: ["down", "left"],
+      0xb6: ["up", "right"],
+      0xb7: ["up", "left"],
+    };
+    const source = this.assets.collision(this.map, this.x, this.y);
+    const opposite: Record<Direction, Direction> = {
+      down: "up",
+      up: "down",
+      left: "right",
+      right: "left",
+    };
+    if (
+      edges[source]?.includes(direction) ||
+      edges[collision]?.includes(opposite[direction])
+    )
+      return false;
+    const warp = this.map.warps.find((warp) => warp.x === x && warp.y === y);
+    if (warp) {
+      if (
+        !Object.hasOwn(NATIVE_MAPS, warp.targetMap) ||
+        warp.targetWarp === 0 ||
+        warp.targetWarp === 255
+      ) {
+        this.notice = "This destination is not ported yet.";
+        return false;
+      }
+      const target = this.assets.map(warp.targetMap),
+        arrival = target.warps[warp.targetWarp - 1];
+      if (!arrival) throw new Error("Warp destination is invalid.");
+      this.mapId = target.id;
+      this.x = arrival.x;
+      this.y = arrival.y;
+      this.objectDirections.clear();
+      this.direction = "down";
+      const arrivalCollision = this.assets.collision(target, this.x, this.y);
+      const exitY =
+        arrivalCollision === 0x70
+          ? this.y - 1
+          : arrivalCollision === 0x71
+            ? this.y + 1
+            : this.y;
+      if (exitY !== this.y && this.canStand(this.x, exitY)) {
+        this.direction = exitY < this.y ? "up" : "down";
+        this.y = exitY;
+      }
+    } else {
+      this.x = x;
+      this.y = y;
+    }
+    this.tilesWalked++;
+    return true;
+  }
+
+  interact() {
+    if (this.dialogue) {
+      this.advanceDialogue();
+      return;
+    }
+    this.clearNotice();
+    const [dx, dy] = VECTORS[this.direction];
+    let x = this.x + dx,
+      y = this.y + dy;
+    const collision = this.assets.collision(this.map, x, y);
+    if (collision === 0x90) {
+      x += dx;
+      y += dy;
+    }
+    const object = this.objects().find(
+      (object) => object.x === x && object.y === y,
+    );
+    let script: number | undefined;
+    if (object) {
+      if (object.kind !== 0) {
+        this.notice = "This interaction is not ported yet.";
+        return;
+      }
+      script = object.script;
+    } else {
+      const event = this.map.backgroundEvents.find(
+        (event) => event.x === x && event.y === y,
+      );
+      if (event) {
+        if (event.kind >= 5) {
+          this.notice = "This conditional interaction is not ported yet.";
+          return;
+        }
+        const requiredDirection = ["up", "down", "right", "left"][
+          event.kind - 1
+        ];
+        if (event.kind && requiredDirection !== this.direction) return;
+        script = event.script;
+      } else {
+        const standard: Record<number, number> = {
+          0x91: 2,
+          0x97: 9,
+          0x9d: 8,
+          0x96: 6,
+          0x9f: 5,
+        };
+        if (standard[collision] !== undefined && this.direction === "up")
+          script = this.assets.reader.far(
+            SYMBOLS.standardScripts + standard[collision] * 3,
+          );
+      }
+    }
+    if (script === undefined) {
+      this.notice = "Nothing to interact with here.";
+      return;
+    }
+    try {
+      const result = runScript(
+        this.assets.reader,
+        script,
+        this.state,
+        this.name,
+      );
+      if (result.facePlayer && object) {
+        const opposite: Record<Direction, Direction> = {
+          down: "up",
+          up: "down",
+          left: "right",
+          right: "left",
+        };
+        this.objectDirections.set(object.id, opposite[this.direction]);
+      }
+      if (result.pages.length)
+        this.dialogue = { pages: result.pages, index: 0, result };
+      else this.commit(result);
+    } catch (error) {
+      this.notice =
+        "This interaction needs game logic that has not been ported yet. Your progress is unchanged.";
+      this.diagnostic = error instanceof Error ? error.message : String(error);
+    }
+  }
+  advanceDialogue() {
+    if (!this.dialogue) return;
+    if (++this.dialogue.index < this.dialogue.pages.length) return;
+    this.commit(this.dialogue.result);
+    this.dialogue = undefined;
+  }
+  private commit(result: ScriptResult) {
+    this.state = {
+      events: result.events,
+      flags: result.flags,
+      variables: result.variables,
+    };
+    for (const turn of result.turns) {
+      if (DIRECTION_ORDER[turn.direction])
+        this.objectDirections.set(turn.object, DIRECTION_ORDER[turn.direction]);
+    }
+  }
+  save(): NativeSave {
+    // Incomplete interactions are replayed after reload; no partial quest writes.
+    return {
+      format: "crystal-native",
+      version: 1,
+      map: this.mapId,
+      x: this.x,
+      y: this.y,
+      direction: this.direction,
+      name: this.name,
+      avatar: this.avatar,
+      tilesWalked: this.tilesWalked,
+      events: [...this.state.events].sort((a, b) => a - b),
+      flags: [...this.state.flags].sort((a, b) => a - b),
+      variables: { ...this.state.variables },
+    };
+  }
+  restore(value: unknown) {
+    const save = value as NativeSave;
+    const integer = (
+      value: unknown,
+      min: number,
+      max: number,
+    ): value is number =>
+      Number.isInteger(value) && Number(value) >= min && Number(value) <= max;
+    const ids = (value: unknown): value is number[] =>
+      Array.isArray(value) &&
+      value.length <= 2048 &&
+      value.every((value) => integer(value, 0, 0xffff)) &&
+      new Set(value).size === value.length;
+    if (
+      !save ||
+      save.format !== "crystal-native" ||
+      save.version !== 1 ||
+      !Object.hasOwn(NATIVE_MAPS, save.map) ||
+      !integer(save.x, 0, 127) ||
+      !integer(save.y, 0, 127) ||
+      !DIRECTION_ORDER.includes(save.direction) ||
+      typeof save.name !== "string" ||
+      !/^[A-Za-z0-9 -]{1,7}$/.test(save.name) ||
+      !["chris", "kris"].includes(save.avatar) ||
+      !integer(save.tilesWalked, 0, Number.MAX_SAFE_INTEGER) ||
+      !ids(save.events) ||
+      !ids(save.flags) ||
+      !save.variables ||
+      typeof save.variables !== "object" ||
+      Array.isArray(save.variables) ||
+      Object.entries(save.variables).some(
+        ([id, value]) =>
+          !/^\d+$/.test(id) ||
+          !integer(Number(id), 0, 255) ||
+          !integer(value, 0, 255),
+      )
+    ) {
+      throw new Error(
+        "Invalid native save. Emulator snapshots cannot be imported into this port.",
+      );
+    }
+    const map = this.assets.map(save.map);
+    if (
+      save.x >= map.width ||
+      save.y >= map.height ||
+      this.assets.permission(this.assets.collision(map, save.x, save.y)) !== 0
+    )
+      throw new Error("The saved position is outside the walkable map.");
+    // Validate completely before changing live state.
+    this.mapId = save.map;
+    this.x = save.x;
+    this.y = save.y;
+    this.direction = save.direction;
+    this.name = save.name;
+    this.avatar = save.avatar;
+    this.tilesWalked = save.tilesWalked;
+    this.state = {
+      events: new Set(save.events),
+      flags: new Set(save.flags),
+      variables: { ...save.variables },
+    };
+    this.dialogue = undefined;
+    this.objectDirections.clear();
+    this.clearNotice();
+  }
+}