From 3f37dd087dcc588279a2eba43fd3e1faf79fac1e Mon Sep 17 00:00:00 2001
From: Ashelyn Dawn <ashe@tempest.dev>
Date: Fri, 24 Jul 2020 13:40:56 -0600
Subject: [PATCH] Beginnings of verb hooks and rules engine

---
 src/engine/Parser.ts              | 16 ++--------------
 src/engine/RulesEngine.ts         | 12 ++++++++++--
 src/engine/types/ParsedCommand.ts |  4 ++--
 src/engine/types/Verb.ts          | 17 +++++++++++++++--
 src/engine/types/VerbBuilder.ts   | 29 +++++++++++++++++++++++++++++
 5 files changed, 58 insertions(+), 20 deletions(-)
 create mode 100644 src/engine/types/VerbBuilder.ts

diff --git a/src/engine/Parser.ts b/src/engine/Parser.ts
index 57a1369..663c193 100644
--- a/src/engine/Parser.ts
+++ b/src/engine/Parser.ts
@@ -2,6 +2,7 @@ import Game from "./Game";
 import RulesEngine from './RulesEngine'
 import ParsedCommand, { InvalidCommandDetails } from "./types/ParsedCommand";
 import Verb from './types/Verb';
+import VerbBuilder from "./types/VerbBuilder";
 
 export default class Parser {
   private game : Game
@@ -27,7 +28,7 @@ export default class Parser {
     if(validationResult.validCommands.length < 1) {
       this.handleError(validationResult.invalidCommands)
     } else {
-      // TODO: Do the thing
+      this.engine.runCommand(validationResult.validCommands[0])
     }
 
     this.game.saveDraft()
@@ -71,16 +72,3 @@ export default class Parser {
     return new VerbBuilder(verb)
   }
 }
-
-class VerbBuilder {
-  private verb : Verb
-
-  constructor(verb : Verb) {
-    this.verb = verb
-  }
-
-  as(template : string) : VerbBuilder {
-    this.verb.understand(template)
-    return this
-  }
-}
diff --git a/src/engine/RulesEngine.ts b/src/engine/RulesEngine.ts
index 2272c61..28635e3 100644
--- a/src/engine/RulesEngine.ts
+++ b/src/engine/RulesEngine.ts
@@ -1,4 +1,12 @@
+import { ValidCommandDetails } from "./types/ParsedCommand";
+
+// This class allows for hooking up "global events" for things such as checking
+// victory conditions, acting when play begins, or other such things.  These
+// event types are different from player actions, which are all considered
+// "command" events
 export default class RulesEngine {
-  // constructor() {
-  // }
+
+  runCommand(action: ValidCommandDetails) {
+
+  }
 }
diff --git a/src/engine/types/ParsedCommand.ts b/src/engine/types/ParsedCommand.ts
index b462618..8c27f85 100644
--- a/src/engine/types/ParsedCommand.ts
+++ b/src/engine/types/ParsedCommand.ts
@@ -43,7 +43,7 @@ export enum ParsingErrorSeverity {
   NoSuchObject = 1
 }
 
-export type ValidCommandDetails = {isValid: true, command: ParsedCommand, subject: GameObject | null, object: GameObject | null}
+export type ValidCommandDetails = {isValid: true, verb: Verb, subject: GameObject | null, object: GameObject | null}
 export type InvalidCommandDetails = {isValid: false, command: ParsedCommand, reason: string, severity: ParsingErrorSeverity}
 
 export default class ParsedCommand {
@@ -99,7 +99,7 @@ export default class ParsedCommand {
 
     return {
       isValid: true,
-      command: this,
+      verb: this.verb,
       subject,
       object
     }
diff --git a/src/engine/types/Verb.ts b/src/engine/types/Verb.ts
index 096a7eb..5f0761d 100644
--- a/src/engine/types/Verb.ts
+++ b/src/engine/types/Verb.ts
@@ -1,17 +1,30 @@
-import ParsedCommand, {TokenType, ParsedTokenLiteral, ParsedTokenExpression} from './ParsedCommand'
+import ParsedCommand, {TokenType, ParsedTokenLiteral, ParsedTokenExpression, ValidCommandDetails} from './ParsedCommand'
 import NounPosition from './NounPosition'
 import { ObjectType } from './GameState'
+import Game from "../Game"
+
+export type VerbAction = (action : ValidCommandDetails, game : Game) => void
 
 export default class Verb {
   static expressionRegex = /^\[([a-z|]+)\]$/
+  private templates : Template[] = []
 
   readonly name : string
-  private templates : Template[] = []
+
+  private hooks : {before: VerbAction[], after : VerbAction[], carryOut: VerbAction[]} = {
+    before: [],
+    after: [],
+    carryOut: []
+  }
 
   constructor(name : string) {
     this.name = name
   }
 
+  on(type : 'before' | 'after' | 'carryOut', action : VerbAction) {
+    this.hooks[type].push(action)
+  }
+
   understand(templateString : string) {
     const words : string[] = templateString.split(' ')
     const tokens : TemplateToken[] = words.map((word : string) => {
diff --git a/src/engine/types/VerbBuilder.ts b/src/engine/types/VerbBuilder.ts
new file mode 100644
index 0000000..dc357a4
--- /dev/null
+++ b/src/engine/types/VerbBuilder.ts
@@ -0,0 +1,29 @@
+import Verb, { VerbAction } from "./Verb"
+
+export default class VerbBuilder {
+  private verb : Verb
+
+  constructor(verb : Verb) {
+    this.verb = verb
+  }
+
+  as(template : string) : VerbBuilder {
+    this.verb.understand(template)
+    return this
+  }
+
+  before(callback : VerbAction) : VerbBuilder {
+    this.verb.on('before', callback)
+    return this
+  }
+
+  carryOut(callback : VerbAction) : VerbBuilder {
+    this.verb.on('carryOut', callback)
+    return this
+  }
+
+  after(callback : VerbAction) : VerbBuilder {
+    this.verb.on('after', callback)
+    return this
+  }
+}