Listing 11.18 - Letting users interact with the game via an interface object
JS Bin
var getGame = function () {
// The spacer namespace
var spacer = {
blank: function () {
return "";
},
newLine: function () {
return "\n";
},
line: function (length, character) {
var longString = "****************************************";
longString += "----------------------------------------";
longString += "========================================";
longString += "++++++++++++++++++++++++++++++++++++++++";
longString += " ";
length = Math.max(0, length);
length = Math.min(40, length);
return longString.substr(longString.indexOf(character), length);
},
wrap : function (text, length, character) {
var padLength = length - text.length - 3;
var wrapText = character + " " + text;
wrapText += spacer.line(padLength, " ");
wrapText += character;
return wrapText;
},
box: function (text, length, character) {
var boxText = spacer.newLine();
boxText += spacer.line(length, character) + spacer.newLine();
boxText += spacer.wrap(text, length, character) + spacer.newLine();
boxText += spacer.line(length, character) + spacer.newLine();
return boxText;
}
};
// Constructors
var Player = function (name, health) {
var newLine = spacer.newLine();
var items = [];
var place = null;
var getNameInfo = function () {
return name;
};
var getHealthInfo = function () {
return "(" + health + ")";
};
var getItemsInfo = function () {
var itemsString = "Items:" + newLine;
items.forEach(function (item, i) {
itemsString += " - " + item + newLine;
});
return itemsString;
};
var getTitleInfo = function () {
return getNameInfo() + " " + getHealthInfo();
};
var getInfo = function () {
var info = spacer.box(getTitleInfo(), 40, "*");
info += " " + getItemsInfo();
info += spacer.line(40, "*");
info += newLine;
return info;
};
this.addItem = function (item) {
items.push(item);
};
this.setPlace = function (destination) {
place = destination;
};
this.getPlace = function () {
return place;
};
this.showInfo = function (character) {
console.log(getInfo(character));
};
};
var Place = function (title, description) {
var newLine = spacer.newLine();
var items = [];
var exits = {};
var getItemsInfo = function () {
var itemsString = "Items: " + newLine;
items.forEach(function (item) {
itemsString += " - " + item;
itemsString += newLine;
});
return itemsString;
};
var getExitsInfo = function () {
var exitsString = "Exits from " + title;
exitsString += ":" + newLine;
Object.keys(exits).forEach(function (key) {
exitsString += " - " + key;
exitsString += newLine;
});
return exitsString;
};
var getTitleInfo = function () {
return spacer.box(title, title.length + 4, "=");
};
var getInfo = function () {
var infoString = getTitleInfo();
infoString += description;
infoString += newLine + newLine;
infoString += getItemsInfo() + newLine;
infoString += getExitsInfo();
infoString += spacer.line(40, "=") + newLine;
return infoString;
};
this.showInfo = function () {
console.log(getInfo());
};
this.addItem = function (item) {
items.push(item);
};
this.addExit = function (direction, exit) {
exits[direction] = exit;
};
this.getExit = function (direction) {
return exits[direction];
};
this.getLastItem = function () {
return items.pop();
};
};
// Console update function
var render = function () {
console.clear();
player.getPlace().showInfo();
player.showInfo();
};
// Create some places
var kitchen = new Place(
"The Kitchen",
"You are in a kitchen. There is a disturbing smell."
);
var library = new Place(
"The Old Library",
"You are in a library. Dusty books line the walls."
);
var garden = new Place(
"The Kitchen Garden",
"You are in a small, walled garden."
);
var cupboard = new Place(
"The Kitchen Cupboard",
"You are in a cupboard. It's surprisingly roomy."
);
// Add items and exits to places
kitchen.addItem("a piece of cheese");
library.addItem("a rusty key");
cupboard.addItem("a tin of spam");
kitchen.addExit("south", library);
kitchen.addExit("west", garden);
kitchen.addExit("east", cupboard);
library.addExit("north", kitchen);
garden.addExit("east", kitchen);
cupboard.addExit("west", kitchen);
// Game initialization
var player = new Player("Kandra", 50);
player.addItem("The Sword of Doom");
player.setPlace(kitchen);
render();
// Return the public interface
return {
go: function (direction) {
var place = player.getPlace();
var destination = place.getExit(direction);
player.setPlace(destination);
render();
return "";
},
get: function () {
var place = player.getPlace();
var item = place.getLastItem();
player.addItem(item);
render();
return "";
}
};
};
var game = getGame();
