feat: basic ux

src/actors/link.js

@@ -0,0 +1,97 @@
+// Link: computer-controlled. Milestones 4-5-8 slice:
+//   seek  -> walk to the nearest pot
+//   throw -> pick it up and hurl it (pots.js handles the arc + shatter)
+//   leave -> no pots left: walk to the exit gap and off-screen (ends the round)
+// Distractions (grass/chickens) arrive in a later milestone.
+
+import { TILE, LINK_SPEED } from "../config.js";
+import { visual } from "../sprites.js";
+import { throwPot } from "../pots.js";
+
+const INTERACT_DIST = TILE * 0.8;
+
+export function addLink(k, world, onLeave) {
+  const p = world.tc(world.level.linkSpawn);
+  const link = k.add([
+    ...visual(k, "link"),
+    k.pos(p),
+    k.area(),
+    k.body(),
+    k.state("seek", ["seek", "throw", "leave"]),
+    "link",
+  ]);
+
+  // Move toward a world position; returns distance remaining.
+  const stepToward = (target) => {
+    const d = target.sub(link.pos);
+    const dist = d.len();
+    if (dist > 1) link.move(d.unit().scale(LINK_SPEED));
+    return dist;
+  };
+
+  const nearestPot = () => {
+    const pots = k.get("pot");
+    let best = null;
+    let bestD = Infinity;
+    for (const pot of pots) {
+      const d = pot.pos.dist(link.pos);
+      if (d < bestD) {
+        bestD = d;
+        best = pot;
+      }
+    }
+    return best;
+  };
+
+  // --- SEEK ---
+  link.onStateUpdate("seek", () => {
+    const pot = nearestPot();
+    if (!pot) {
+      link.enterState("leave");
+      return;
+    }
+    if (stepToward(pot.pos) <= INTERACT_DIST) {
+      link.target = pot;
+      link.enterState("throw");
+    }
+  });
+
+  // --- THROW ---
+  link.onStateEnter("throw", () => {
+    const pot = link.target;
+    if (!pot || pot.destroyed) {
+      link.enterState("seek");
+      return;
+    }
+    const at = pot.pos.clone();
+    pot.destroy(); // picked up
+    link.throwing = true;
+    throwPot(k, world, at, () => {
+      link.throwing = false;
+      link.enterState("seek");
+    });
+  });
+  // Stand still while the throw animation plays.
+
+  // --- LEAVE ---
+  link.onStateEnter("leave", () => {
+    link.leaving = true;
+  });
+  link.onStateUpdate("leave", () => {
+    const exitPos = world.tc(world.level.exit);
+    stepToward(exitPos);
+    // Once he reaches / passes the exit gap, he's gone.
+    if (link.pos.dist(exitPos) < TILE * 0.5) {
+      if (!link.gone) {
+        link.gone = true;
+        onLeave && onLeave();
+      }
+    }
+  });
+
+  link.onUpdate(() => {
+    link.z = link.pos.y;
+  });
+
+  return link;
+}