Huge rewrite to NESBank. Still some tweaking to be done

app/js/models/NESBank.js

 import NESPalette from "/app/js/models/NESPalette.js";
 
 
+function CnvIdx(x, y, am, off){
+  var res = {
+    side: 0,
+    tileidx: 0,
+    x: 0,
+    y: 0
+  }
+
+  switch(am){
+  case NESBank.ACCESSMODE_8K:
+    res.side = (x > 128) ? 1 : 0;
+    x -= (res.side === 1) ? 128, 0;
+    res.tileidx = (Math.floor(y/8) * 16) + Math.floor(x / 8);
+    break;
+  case NESBank.ACCESSMODE_4K:
+    res.side = off;
+    res.tileidx = (Math.floor(y/8) * 16) + Math.floor(x / 8);
+    break;
+  case NESBank.ACCESSMODE_2K:
+    res.side = Math.floor(off * 0.5);
+    res.tileidx = (res.side*32) + ((Math.floor(y/8) * 16) + Math.floor(x / 8));
+    break;
+  case NESBank.ACCESSMODE_1K:
+    res.side = Math.floor(off * 0.25);
+    off -= (off > 3) ? 4 : 0;
+    res.tileidx = (off * 16) + ((Math.floor(y/8) * 16) + Math.floor(x / 8));
+    break;
+  }
+
+  res.x = x%8;
+  res.y = y%8;
+
+  return res;
+}
+
 function LRIdx2TileIdxCo(index, lid){
   if (isNaN(lid) || lid < 0 || lid > 2){
     lid = 2;
   return res;
 }
 
+
 export default class NESBank extends ISurface{
   constructor(){
     super();
     this.__AccessMode = NESBank.ACCESSMODE_8K;
     this.__AccessOffset = 0;
 
-    var handle_datachanged = Utils.debounce((function(side){
-      if ((side == 0 && (this.__AccessMode == 0 || this.__AccessMode == 2)) ||
-        (side == 1 && (this.__AccessMode == 1 || this.__AccessMode == 2))){
+    this.__emitsEnabled = true;
+
+    var handle_datachanged = Utils.debounce((function(side, idx){
+      var sendEmit = false;
+      switch(this.__AccessMode){
+        case NESBank.ACCESSMODE_1K:
+          if (side === Math.floor(this.__AccessOffset / 4){
+            if (Math.floor(idx / 64) === Math.floor(this.__AccessOffset/4))
+              sendEmit = true;
+          }
+          break;
+        case NESBank.ACCESSMODE_2K:
+          if (side === Math.floor(this.__AccessOffset / 2){
+            if (Math.floor(idx / 128) === Math.floor(this.__AccessOffset/2))
+              sendEmit = true;
+          }
+          break;
+        case NESBank.ACCESSMODE_4K:
+          if (side === this.__AccessOffset)
+            sendEmit = true;
+          break;
+        case NESBank.ACCESSMODE_8K:
+          sendEmit = true;
+      }
+
+      if (sendEmit && this.__emitsEnabled){
         this.emit("data_changed");
       }
     }).bind(this), 250);
 
     for (var i=0; i < 256; i++){
       this.__LP.push(new NESTile());
-      this.__LP[i].listen("data_changed", handle_datachanged.bind(this, 0));
+      this.__LP[i].listen("data_changed", handle_datachanged.bind(this, 0, i));
       this.__RP.push(new NESTile());
-      this.__RP[i].listen("data_changed", handle_datachanged.bind(this, 1));
+      this.__RP[i].listen("data_changed", handle_datachanged.bind(this, 1, i));
     }
 
     this.__palette = null;
     if (!Utils.isInt(m))
       throw new TypeError("Access mode expected to be integer.");
     switch(m){
-      case NESBank.ACCESSMODE_SPRITE:
-        this.__AccessMode = NESBank.ACCESSMODE_SPRITE;
-        this.emit("data_changed");
+      case NESBank.ACCESSMODE_8K:
+        this.__AccessMode = NESBank.ACCESSMODE_8K;
+        this.__AccessOffset = 0; 
         break;
-      case NESBank.ACCESSMODE_BACKGROUND:
-        this.__AccessMode = NESBank.ACCESSMODE_BACKGROUND;
-        this.emit("data_changed");
+      case NESBank.ACCESSMODE_4K:
+        if (this.__AccessOffset > 1){
+          switch(this.__AccessMode){
+          case NESBank.ACCESSMODE_2K:
+            this.__AccessOffset = Math.floor(this.__AccessOffset * 0.5);
+            break;
+          case NESBank.ACCESSMODE_1K:
+            this.__AccessOffset = Math.floor(this.__AccessOffset * 0.25);
+            break;
+          }
+        }
+        this.__AccessMode = NESBank.ACCESSMODE_4K
         break;
-      case NESBank.ACCESSMODE_FULL:
-        this.__AccessMode = NESBank.ACCESSMODE_FULL;
-        this.emit("data_changed");
+      case NESBank.ACCESSMODE_2K:
+        switch(this.__AccessMode){
+        case NESBank.ACCESSMODE_8K:
+          this.__AccessOffset = 0;
+          break;
+        case NESBank.ACCESSMODE_4K:
+          this.__AccessOffset *= 2;
+          break;
+        case NESBank.ACCESSMODE_1K:
+          this.__AccessOffset = Math.floor(this.__AccessOffset * 0.5);
+          break;
+        }
+        this.__AccessMode = NESBank.ACCESSMODE_2K;
         break;
+      case NESBank.ACCESSMODE_1K:
+        switch(this.__AccessMode){
+        case NESBank.ACCESSMODE_8K:
+          this.__AccessOffset = 0;
+          break;
+        case NESBank.ACCESSMODE_4K:
+          this.__AccessOffset *= 4;
+          break;
+        case NESBank.ACCESSMODE_2K:
+          this.__AccessOffset *= 2;
+          break;
+        }
+        this.__AccessMode = NESBank.ACCESSMODE_1K;
+        break;
+
+      default:
+        throw new ValueError("Unknown Access Mode.");
     }
+
+    if (this.__emitsEnabled)
+      this.emit("data_changed");
+  }
+
+  get access_offset(){return this.__AccessOffset;}
+  set access_offset(o){
+    if (!Utils.isInt(m))
+      throw new TypeError("Access offset expected to be integer.");
+    switch (this.__AccessMode){
+      case NESBank.ACCESSMODE_8K:
+        if (o !== 0)
+          throw new RangeError("Access Offset is out of bounds based on current Access Mode.");
+        break;
+      case NESBank.ACCESSMODE_4K:
+        if (o !== 0 && o !== 1)
+          throw new RangeError("Access Offset is out of bounds based on current Access Mode.");
+        break;
+      case NESBank.ACCESSMODE_2K:
+        if (o < 0 || o >= 4)
+          throw new RangeError("Access Offset is out of bounds based on current Access Mode.");
+        break;
+      case NESBank.ACCESSMODE_1K:
+        if (o < 0 || o >= 8)
+          throw new RangeError("Access Offset is out of bounds based on current Access Mode.");
+        break;
+    }
+
+    this.__AccessOffset = m;
+    if (this.__emitsEnabled)
+      this.emit("data_changed");
   }
 
   get json(){
   }
 
   get chr(){
-    var buff = new Uint8Array(8192);
+    var buff = null;
     var offset = 0;
-    this.__LP.forEach(function(i){
-      buff.set(i.chr, offset);
-      offset += 16;
-    });
-    this.__RP.forEach(function(i){
-      buff.set(i.chr, offset);
-      offset += 16;
-    });
+    switch (this.__AccessMode){
+      case NESBank.ACCESSMODE_8K:
+        buff = new Uint8Array(8192);
+        this.__LP.forEach((i) => {
+          buff.set(i.chr, offset);
+          offset += 16;
+        });
+        this.__RP.forEach((i) => {
+          buff.set(i.chr, offset);
+          offset += 16;
+        });
+        break;
+
+      case NESBank.ACCESSMODE_4K:
+        buff = new Uint8Array(4096);
+        var list = (this.__AccessOffset === 0) ? this.__LP : this.__RP;
+        list.forEach((i) => {
+          buff.set(i.chr, offset);
+          offset += 16;
+        });
+        break;
+
+      case NESBank.ACCESSMODE_2K:
+        buff = new Uint8Array(2048);
+        var list = (this.__AccessOffset < 2) ? this.__LP : this.__RP;
+        var s = Math.floor(this.__AccessOffset * 0.5) * 128;
+        var e = s + 128;
+        for (let i=s; i < e; i++){
+          buff.set(list[i].chr, offset);
+          offset += 16;
+        }
+        break;
+
+      case NESBank.ACCESSMODE_1K:
+        buff = new Uint8Array(1024);
+        var list = (this.__AccessOffset < 4) ? this.__LP : this.__RP;
+        var s = Math.floor(this.__AccessOffset * 0.25) * 64;
+        var e = s + 64;
+        for (let i=s; i < e; i++){
+          buff.set(list[i].chr, offset);
+          offset += 16;
+        }
+        break;
+    } 
     return buff;
   }
 
-  set chr(buff){
+  /*set chr(buff){
     if (!(buff instanceof Uint8Array))
       throw new TypeError("Expected Uint8Array buffer.");
     if (buff.length !== 8192)
       i.chr = buff.slice(offset, offset+15);
       offset += 16;
     });
-  }
+  }*/
 
   get base64(){
     var b = "";
     }
   }
 
-  get width(){return (this.__AccessMode == NESBank.ACCESSMODE_FULL) ? 256 : 128;}
-  get height(){return 128;}
+  get width(){return (this.__AccessMode == NESBank.ACCESSMODE_8K) ? 256 : 128;}
+  get height(){
+    switch(this.__AccessMode){
+      case NESBank.ACCESSMODE_2K:
+        return 64;
+      case NESBank.ACCESSMODE_1K:
+        return 32;
+    }
+    return 128;
+  }
   get length(){return this.width * this.height;}
 
   get coloridx(){
         prop = parseInt(prop);
         if (prop < 0 || prop >= len)
           return NESPalette.Default[4];
-        
-        var res = LRIdx2TileIdxCo(prop, this.__AccessMode);
-        var list = (res.lid === 0) ? obj.__LP : obj.__RP; 
-        return list[res.index].getPixelIndex(res.x, res.y);
+
+        var x = Math.floor(prop % this.width);
+        var y = Math.floor(prop / this.width);
+        var res = CnvIdx(x, y, this.__AccessMode, this.__AccessOffset);
+        var list = (res.side === 0) ? obj.__LP : obj.__RP;
+        return list[res.tileidx].getPixelIndex(res.x, res.y);
       },
 
       set:function(obj, prop, value){
           throw new RangeError("Index out of bounds.");
         if (value < 0 || value >= 4)
           throw new RangeError("Color index out of bounds.");
-        
-        var res = LRIdx2TileIdxCo(prop, this.__AccessMode);
-        var list = (res.lid === 0) ? obj.__LP : obj.__RP;
-        list[res.index].setPixelIndex(res.x, res.y, value);
+       
+        var x = Math.floor(prop % this.width);
+        var y = Math.floor(prop / this.width);
+        var res = CnvIdx(x, y, this.__AccessMode, this.__AccessOffset);
+        var list = (res.side === 0) ? obj.__LP : obj.__RP;
+        list[res.tileidx].setPixelIndex(res.x, res.y, value);
         return true;
       }
     });
     return (new NESBank()).copy(this);
   }
 
+
+  getCHR(mode, offset){
+    this.__emitsEnabled = false;
+    var oam = this.access_mode;
+    var oao = this.access_offset;
+
+    try{
+      this.access_mode = mode;
+      this.access_offset = offset;
+    } catch (e){
+      this.access_mode = oam;
+      this.access_offset = oao;
+      this.__emitsEnabled = true;
+      throw e;
+    }
+
+    var chr = this.chr;
+    this.access_mode = oam;
+    this.access_offset = oao;
+    this.__emitsEnabled = true;
+
+    return chr;
+  }
+
+  setCHR(buff, offset){
+    if (!Utils.isInt(offset) || offset < 0)
+      offset = 0;
+
+    var idx = 0;
+    switch(buff.length){
+      case 8192:
+        this.__LP.forEach((i) => {
+          i.chr = buff.slice(idx, idx+15);
+          idx += 16;
+        });
+        this.__RP.forEach((i) => {
+          i.chr = buff.slice(idx, idx+15);
+          idx += 16;
+        });
+        break;
+      case 4096:
+        if (offset >= 2)
+          throw new RangeError("Offset mismatch based on Buffer length.");
+        var list = (offset === 0) ? this.__LP : this.__RP;
+        list.forEach((i) => {
+          i.chr = buff.slice(idx, idx+15);
+          idx += 16;
+        });
+        break;
+      case 2048:
+        if (offset >= 4)
+          throw new RangeError("Offset mismatch based on Buffer length.");
+        var list = (offset < 2) ? this.__LP : this.__RP;
+        var s = Math.floor(offset * 0.5) * 128;
+        var e = s + 128;
+        for (let i=s; i < e; i++){
+          list[i].chr = buff.slice(idx, idx+15);
+          idx += 16;
+        }
+        break;
+      case 1024:
+        if (offset >= 8)
+          throw new RangeError("Offset mismatch based on Buffer length.");
+        var list = (offset < 4) ? this.__LP : this.__RP;
+        var s = Math.floor(this.__AccessOffset * 0.25) * 64;
+        var e = s + 64;
+        for (let i=s; i < e; i++){
+          list[i].chr = buff.slice(idx, idx+15);
+          idx += 16;
+        }
+        break;
+      default:
+        throw new RangeError("Buffer length does not match any of the supported bank sizes.");
+    }
+
+    return this;
+  }
+
   getColor(x,y){
     if (x < 0 || x >= this.width || y < 0 || y >= this.height)
       return this.__default_pi[4]; 
 
-    var res = LRIdx2TileIdxCo((y*this.width)+x, this.__AccessMode);
-    var list = (res.lid === 0) ? this.__LP : this.__RP;
-    var pi = list[res.index].paletteIndex + ((res.lid === 0) ? 4 : 0);
-    var ci = list[res.index].getPixelIndex(res.x, res.y);
+    var res = CnvIdx(x, y, this.__AccessMode, this.__AccessOffset);
+    var list = (res.side === 0) ? this.__LP : this.__RP;
+    var pi = list[res.tileidx].paletteIndex + ((res.side === 0) ? 4 : 0);
+    var ci = list[res.tileidx].getPixelIndex(res.x, res.y);
 
     if (this.__palette !== null){
       return this.__palette.get_palette_color(pi, ci);
     if (x < 0 || x >= this.width || y < 0 || y >= this.height)
       return {pi: -1, ci:-1};
 
-    var res = LRIdx2TileIdxCo((y*this.width)+x, this.__AccessMode);
-    var list = (res.lid === 0) ? this.__LP : this.__RP; 
+    var res = CnvIdx(x, y, this.__AccessMode, this.__AccessOffset);
+    var list = (res.side === 0) ? this.__LP : this.__RP; 
     return {
-      pi: list[res.index].paletteIndex,
-      ci: list[res.index].getPixelIndex(res.x, res.y)
+      pi: list[res.tileidx].paletteIndex,
+      ci: list[res.tileidx].getPixelIndex(res.x, res.y)
     };
   }
 
       this.coloridx[(y*this.width)+x] = ci;
     } else {
 
-      var res = LRIdx2TileIdxCo((y*this.width)+x, this.__AccessMode);
-      var list = (res.lid === 0) ? this.__LP : this.__RP;
+      var res = CnvIdx(x, y, this.__AccessMode, this.__AccessOffset);
+      var list = (res.side === 0) ? this.__LP : this.__RP;
 
-      list[res.index].paletteIndex = pi;
-      list[res.index].setPixelIndex(res.x, res.y, ci);
+      list[res.tileidx].paletteIndex = pi;
+      list[res.tileidx].setPixelIndex(res.x, res.y, ci);
     }
     return this;
   }