1 files changed, 110 insertions, 0 deletions
diff --git a/src/systems/logic.js b/src/systems/logic.js
new file mode 100644
index 0000000..8e3bbc0
--- /dev/null
+++ b/src/systems/logic.js
@@ -0,0 +1,110 @@
+game.system.Logic = (entitiesGrid) => {
+  "use strict";
+  let currentVerbRules = [];
+  const isWord = (entity) => entity.hasComponent("gridPosition") && (entity.hasComponent("verb") || entity.hasComponent("noun"));
+  
+  const getFirstWordEntity = (gridPosition) => {
+    if (!equivalence(gridPosition, clamp(gridPosition, game.config.xDim, game.config.yDim))) {
+      return null;
+    }
+    for (let entity of entitiesGrid[gridPosition.y][gridPosition.x].values()) {
+      if (isWord(entity)) {
+        return entity;
+      }
+    }
+    return null;
+  };
+
+  const verbActionsToComponent = {
+    "stop": game.components.Stop(),
+    "push": game.components.Pushable(),
+    "you": game.components.Controllable({controls: ['left', 'right', 'up', 'down']}),
+    
+  };
+
+  const nounsToEntityCreators = {
+    "rock": game.createRock,
+    "wall": game.createWall,
+  };
+  
+  const doOnRule = (rule, entities, direction) => {
+    const [applyee, application] = [entities[rule[0]], entities[rule[1]]];
+    const changedEntityIds = [];
+    if (applyee.hasComponent("noun")) {
+      const entityName = applyee.components.noun.select;
+      if (application.hasComponent("verb")) {
+        const verb = application.components.verb.action;
+        if (direction == "apply") {
+          currentVerbRules.push(rule);
+        }
+        for (let id in entities) {
+          if (entities[id].hasComponent("name") && entities[id].components.name.selector == entityName) {
+            changedEntityIds.push(id);
+            const component = verbActionsToComponent[verb];
+            if (component) {
+              if (direction == "apply") {              
+                entities[id].addComponent(component);
+              } else if (direction == "deapply") {
+                entities[id].removeComponent(component.name);
+              }
+            }
+          }
+        }
+      }
+      if (application.hasComponent("noun")) {
+        const applicationEntityName = application.components.noun.select;
+        for (let id in entities) {
+          if (entities[id].hasComponent("name") && entities[id].components.name.selector == entityName) {
+            const e = nounsToEntityCreators[applicationEntityName]();
+            entities[id].components.name = e.components.name;
+            entities[id].components.sprite = e.components.sprite;
+          }
+        }
+      }
+    };
+    return changedEntityIds;
+  };
+  
+  const parseRules = (entities) => {
+    currentVerbRules.map((rule) => doOnRule(rule, entities, "deapply"));
+    currentVerbRules = [];
+    const isWordGridPositions = [];
+    const changedEntityIds = new Set();
+    entitiesGrid.forEach((row) => row.forEach((entitiesInCell) => {
+      for (let entity of entitiesInCell.values()) {
+        if (isWord(entity) && entity.hasComponent("verb") && entity.components.verb.action == "Is") {
+          isWordGridPositions.push(entity.components.gridPosition);
+        }
+      }
+    }));
+    let newRules = [];
+    isWordGridPositions.forEach((gridPosition) => {
+      const east = getFirstWordEntity({y: gridPosition.y, x: gridPosition.x - 1});
+      const west = getFirstWordEntity({y: gridPosition.y, x: gridPosition.x + 1});
+      const north = getFirstWordEntity({x: gridPosition.x, y: gridPosition.y - 1});
+      const south = getFirstWordEntity({x: gridPosition.x, y: gridPosition.y + 1});
+
+      if (east && west) {
+        newRules.push([east.id, west.id]);
+      }
+      if (north && south) {
+        newRules.push([north.id, south.id]);
+      }
+    });
+    newRules = newRules.sort((a, b) => (entities[b[1]].hasComponent("noun") ? 1 : -1) - (entities[a[1]].hasComponent("noun") ? 1 : -1));
+    newRules.map((rule) => doOnRule(rule, entities, "apply").map((id) => changedEntityIds.add(id)));
+    return changedEntityIds;
+  };
+  
+  const update = (_elapsedTime, entities, changedIds) => {
+    for (let id of changedIds) {
+      const changed = entities[id];
+      if (changed.hasComponent("verb") || changed.hasComponent("noun")) {
+        return parseRules(entities);
+      }
+    }
+    return new Set();
+  };
+
+  return { update, parseRules };
+};