allow multiple component matching and entity id binding

src/query-parser/match.js

@@ -46,7 +46,7 @@ export const node = map(
 
 export const edge = map(
   x => new Edge(x),
-  bracketed(components, Bracket.Square)
+  bracketed(component, Bracket.Square)
 )
 
 const arrowRight = map(() => Direction.Right, seq(Hyphen, Bracket.Angle.Right))

src/query-parser/types.js

@@ -1,4 +1,3 @@
-import { pipe } from 'bitecs'
 import { assoc, assocPath, is, nth } from '../fn.js'
 
 class Value {
@@ -8,6 +7,10 @@ class Value {
     this.#value = value
   }
 
+  toString() {
+    return this.#value.toString()
+  }
+
   get value() {
     return this.#value?.value ?? this.#value
   }
@@ -28,10 +31,6 @@ export class Identifier extends Value {
     super(value)
   }
 
-  toString() {
-    return this.value.toString()
-  }
-
   from(component) {
     return component
   }
@@ -189,33 +188,20 @@ export class ReturnValues {
 
   #forComponentType(value, type) {
     if (this.#isTag(type)) {
-      return () => ({})
+      return {}
     } else if (typeof type === 'function') {
       return type
     } else {
-      return value.from(type)
-      //return Object.fromEntries(
-      //  Object.entries(type).map(([k, v]) => [k, v[entity]])
-      //)
+      return entity => value.from(type)[entity]
     }
   }
 
   // TODO: adjust froms to accent entity, return data with built up objects as necessary
   from(components) {
-    /*
-     * const { entity, query: { components } } = node
-     * const returns2 = components.map(c => ({ ...c, returnValue: returns.find(x => x.equals(c.name)) }))
-     * returns2.map(({ returnValue, type }) => getValue(returnValue, type, entity))
-     * const values = returns2.filter(({ name }) => returns.includes(name))
-     *   .map(({ name, type, returnValue }) => ({ [name]: getValue(returnValue, type, entity) }))
-     * const values = components.filter(({ name }) => returns.includes(name))
-     *   .map(({ name, type }) => ({ [name]: getValue(type, entity) }))
-     * return Object.assign(obj, ...values)
-     */
+    const values = components.map(cmp => ({ ...cmp, rv: this.findName(cmp.name) }))
+      .map(({ type, rv }) => new ReturnValue(rv, this.#forComponentType(rv, type)))
 
-    const values = components.map(component => ({ ...component, returnValue: this.findName(component.name) }))
-      .map(({ name, type, returnValue }) => ([returnValue.toString(), this.#forComponentType(returnValue, type)]))
-    console.log(this, values)
+    return entity => values.reduce((acc, rv) => Object.assign(acc, rv.withEntity(entity)), {})
   }
 
   find(fn) {
@@ -235,6 +221,21 @@ export class ReturnValues {
   }
 }
 
+class ReturnValue {
+  #value
+  #getter
+
+  constructor(value, getter) {
+    this.#value = value
+    this.#getter = getter
+  }
+
+  withEntity(entity) {
+    return  assocPath(this.#value.toString(), this.#getter(entity), {})
+  }
+}
+
+
 export class KeyValuePair {
   constructor(key, value) {
     this.key = key

src/query.js

@@ -26,7 +26,7 @@ const prepareQuery = (query, component) => {
   } else {
     const components = match.components.map(nodeComponent(component))
     const types = components.filter(notEntity).map(prop('type'))
-    return { components, relationship, query: defineQuery(types), schema: query }
+    return { components, relationship, getReturns: returnValues.from(components), query: defineQuery(types), schema: query }
   }
 }
 
@@ -95,38 +95,10 @@ const executeQuery = curry((query, world) => {
   }
 })
 
-const isTag = type => (
-  type && Object.getOwnPropertySymbols(type).find(
-    (s) => s.description === 'tagStore'
-  ) || false
-)
-
-const getValue = (returnValue, type, entity) => {
-  if (isTag(type)) {
-    return {}
-  } else if (typeof type === 'function') {
-    return type(entity)
-  } else {
-    return returnValue.from(type)
-    //return Object.fromEntries(
-    //  Object.entries(type).map(([k, v]) => [k, v[entity]])
-    //)
-  }
-}
 
 const resolveNode = curry((node, obj) => {
-  const returns = path('query.schema.returnValues', node)
-  const { entity, query: { components } } = node
-  // TODO: do this work in prepareQuery
-  returns.from(components)
-
-  //const returns2 = components.map(c => ({ ...c, returnValue: returns.find(x => x.equals(c.name)) }))
-  //returns2.map(({ returnValue, type }) => getValue(returnValue, type, entity))
-  //const values = returns2.filter(({ name }) => returns.includes(name))
-  //  .map(({ name, type, returnValue }) => ({ [name]: getValue(returnValue, type, entity) }))
-  //const values = components.filter(({ name }) => returns.includes(name))
-  //  .map(({ name, type }) => ({ [name]: getValue(type, entity) }))
-  //return Object.assign(obj, ...values)
+  const { entity, query: { getReturns } } = node
+  return { ...obj, ...getReturns(entity) }
 })
 
 const resolveRelationship = edges => {

tests/query.test.js

@@ -55,6 +55,7 @@ describe('query', () => {
         relate(world, b, Knows, a) // 9
         relate(world, c, Knows, player) // 10
 
+        // tag components should return an object object
         assert.deepEqual(
             query('MATCH (player:Player) RETURN player', engine).unwrap(),
             [{ player: {} }]