From dda51c34677796f50895a159758188284002c558 Mon Sep 17 00:00:00 2001
From: Steven Hugg <hugg@fasterlight.com>
Date: Tue, 8 Feb 2022 06:18:28 -0600
Subject: [PATCH] ecs: asc desc

---
 src/common/ecs/compiler.ts | 21 ++++++++++++---------
 src/common/ecs/ecs.ts      | 38 +++++++++++++++++++++++++++++---------
 2 files changed, 41 insertions(+), 18 deletions(-)

diff --git a/src/common/ecs/compiler.ts b/src/common/ecs/compiler.ts
index 3e452930..30b95465 100644
--- a/src/common/ecs/compiler.ts
+++ b/src/common/ecs/compiler.ts
@@ -2,7 +2,7 @@
 import { mergeLocs, Tokenizer, TokenType } from "../tokenizer";
 import { SourceLocated } from "../workertypes";
 import { newDecoder } from "./decoder";
-import { Action, ArrayType, ComponentType, DataField, DataType, DataValue, ECSError, Entity, EntityArchetype, EntityManager, EntityScope, IntType, Query, RefType, SelectType, SELECT_TYPE, SourceFileExport, System } from "./ecs";
+import { Action, ActionWithJoin, ArrayType, ComponentType, DataField, DataType, DataValue, ECSError, Entity, EntityArchetype, EntityManager, EntityScope, IntType, Query, RefType, SelectType, SELECT_TYPE, SourceFileExport, System } from "./ecs";
 
 export enum ECSTokenType {
     Ellipsis = 'ellipsis',
@@ -224,13 +224,16 @@ export class ECSCompiler extends Tokenizer {
 
     parseAction(): Action {
         // TODO: unused events?
-        let event = this.expectIdent().str;
+        const event = this.expectIdent().str;
         this.expectToken('do');
-        let select = this.expectTokens(SELECT_TYPE).str as SelectType; // TODO: type check?
+        const all_modifiers = ['cyclecritical','asc','desc']; // TODO
+        const modifiers = this.parseModifiers(all_modifiers);
+        // TODO: include modifiers in error msg
+        const select = this.expectTokens(SELECT_TYPE).str as SelectType; // TODO: type check?
         let query = undefined;
         let join = undefined;
         if (select == 'once') {
-            if (this.peekToken().str == '[') this.compileError(`A "${select}" query can't include a query.`)
+            if (this.peekToken().str == '[') this.compileError(`A "${select}" action can't include a query.`)
         } else {
             query = this.parseQuery();
         }
@@ -242,12 +245,12 @@ export class ECSCompiler extends Tokenizer {
             if (!query) { this.compileError(`A "${select}" query can't include a limit.`); }
             else query.limit = this.expectInteger();
         }
-        if (this.ifToken('cyclecritical')) {
-            // TODO
-        }
         let text = this.parseCode();
-        let action = { text, event, query, join, select };
-        return action as Action;
+        let direction = undefined;
+        if (modifiers['asc']) direction = 'asc';
+        else if (modifiers['desc']) direction = 'desc';
+        let action = { text, event, query, join, select, direction };
+        return action as ActionWithJoin;
     }
     
     parseQuery() {
diff --git a/src/common/ecs/ecs.ts b/src/common/ecs/ecs.ts
index d7604f48..40e1a31f 100644
--- a/src/common/ecs/ecs.ts
+++ b/src/common/ecs/ecs.ts
@@ -59,8 +59,6 @@ how to avoid cycle crossing for critical code and data?
 
 */
 
-
-import { data } from "jquery";
 import { SourceLocated, SourceLocation } from "../workertypes";
 
 export class ECSError extends Error {
@@ -132,6 +130,7 @@ export interface ActionOnce extends ActionBase {
 export interface ActionWithQuery extends ActionBase {
     select: 'foreach' | 'join' | 'with' | 'if' | 'select'
     query: Query
+    direction?: 'asc' | 'desc'
 }
 
 export interface ActionWithJoin extends ActionWithQuery {
@@ -191,7 +190,7 @@ interface ComponentFieldPair {
 
 export class Dialect_CA65 {
 
-    ASM_ITERATE_EACH = `
+    ASM_ITERATE_EACH_ASC = `
     ldx #0
 @__each:
     {{%code}}
@@ -201,7 +200,16 @@ export class Dialect_CA65 {
 @__exit:
 `;
 
-    ASM_ITERATE_JOIN = `
+    ASM_ITERATE_EACH_DESC = `
+    ldx #{{%ecount}}-1
+@__each:
+    {{%code}}
+    dex
+    bpl @__each
+@__exit:
+`;
+
+    ASM_ITERATE_JOIN_ASC = `
     ldy #0
 @__each:
     ldx {{%joinfield}},y
@@ -210,6 +218,16 @@ export class Dialect_CA65 {
     cpy #{{%ecount}}
     bne @__each
 @__exit:
+`;
+
+    ASM_ITERATE_JOIN_DESC = `
+    ldy #{{%ecount}}-1
+@__each:
+    ldx {{%joinfield}},y
+    {{%code}}
+    dey
+    bpl @__each
+@__exit:
 `;
 
     ASM_FILTER_RANGE_LO_X = `
@@ -490,8 +508,8 @@ class ActionCPUState {
 }
 
 class ActionEval {
-    em;
-    dialect;
+    em : EntityManager;
+    dialect : Dialect_CA65;
     qr: EntitySet;
     jr: EntitySet | undefined;
     oldState : ActionCPUState;
@@ -675,12 +693,14 @@ class ActionEval {
     __bss_init(args: string[]) {
         return this.scope.allocateInitData(this.scope.bss);
     }
-    wrapCodeInLoop(code: string, action: Action, ents: Entity[], joinfield?: ComponentFieldPair): string {
+    wrapCodeInLoop(code: string, action: ActionWithQuery, ents: Entity[], joinfield?: ComponentFieldPair): string {
         // TODO: check ents
         // TODO: check segment bounds
         // TODO: what if 0 or 1 entitites?
-        let s = this.dialect.ASM_ITERATE_EACH;
-        if (joinfield) s = this.dialect.ASM_ITERATE_JOIN;
+        // TODO: check > 127 or > 255
+        let dir = action.direction;
+        let s = dir == 'desc' ? this.dialect.ASM_ITERATE_EACH_DESC : this.dialect.ASM_ITERATE_EACH_ASC;
+        if (joinfield) s = dir == 'desc' ? this.dialect.ASM_ITERATE_JOIN_DESC : this.dialect.ASM_ITERATE_JOIN_ASC;
         s = s.replace('{{%code}}', code);
         return s;
     }