From e3e6400181616a68d9ea8cdfe34b36655d9fede7 Mon Sep 17 00:00:00 2001
From: Muthu Kumar <muthukumar@thefeathers.in>
Date: Sat, 12 May 2018 18:44:39 +0530
Subject: [PATCH] [slider] wip 0.1.0

---
 package.json         |  2 +-
 structures/deck.js   | 26 --------------------------
 structures/slider.js | 37 +++++++++++++++++++------------------
 3 files changed, 20 insertions(+), 45 deletions(-)
 delete mode 100644 structures/deck.js

diff --git a/package.json b/package.json
index e86fb44..0b06367 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@codefeathers/window",
-  "version": "0.0.1",
+  "version": "0.1.0",
   "description": "A sliding window algorithm to insert a new array into an existing one.",
   "main": "index.js",
   "scripts": {
diff --git a/structures/deck.js b/structures/deck.js
deleted file mode 100644
index 402040d..0000000
--- a/structures/deck.js
+++ /dev/null
@@ -1,26 +0,0 @@
-class Deck extends Array {
-
-	recurse (fn) {
-		let index = 0;
-		const call = (arr, acc = []) => {
-			if(arr[0]) {
-				const res = fn(index++, arr[0]);
-				return call(arr.slice(1), [ res, ...acc ]);
-			}
-			return acc;
-		};
-		return call(this);
-	}
-
-	findIndexAfter(index, predicate) {
-		const self = this;
-		let i = index + 1;
-		while(i < self.length) {
-			if(predicate(self[i])) return i;
-			i++;
-		}
-		return -1;
-	}
-};
-
-module.exports = Deck;
\ No newline at end of file
diff --git a/structures/slider.js b/structures/slider.js
index a4df4d9..8b1ece3 100644
--- a/structures/slider.js
+++ b/structures/slider.js
@@ -1,8 +1,6 @@
 'use strict';
 
-const isEq = require('@codefeathers/iseq/isEq');
-
-const Deck = require('./deck');
+const isEq = require('@codefeathers/iseq');
 
 const wrap = (f, ...x) => (...y) => f(...x, ...y);
 
@@ -13,32 +11,35 @@ class Slider {
 		this.accepting = options.accepting;
 	}
 
-	slide (master, compare) {
+	slide (host, guest) {
 
 		const k = this.windowSize;
 
-		const host = Deck.from(master);
-		const guest = Deck.from(compare);
+		const get = {
+			val: 0,
+			next: () => ++get.val,
+		}
 
 		const startSliding = (window, i) => {
 
 			const firstMatch = host.findIndex(wrap(isEq, window[0]));
-			if(firstMatch !== -1
-				&& window.every((item, j) => host.findIndexAfter(
-														firstMatch,
-														wrap(isEq, window[j])
-													)) !== -1
-			) return [ firstMatch, i ];
-
-			const newWindow = Deck.from(guest.slice(++i, k));
-			if(newWindow.length !== 0 && newWindow.length === k) return startSliding(newWindow, i);
+			if(firstMatch !== -1) {
+				get.val = firstMatch;
+				if(window.every((item, j) => {
+					if(j === 0) return true;
+					return isEq(item, host[get.next()]);
+				})) return [ firstMatch, i ];
+			}
+
+			const nextI = i + 1;
+			const newWindow = guest.slice(nextI, nextI + k);
+			if(newWindow.length === k) return startSliding(newWindow, nextI);
 
 			return [ -1, -1 ];
 
 		};
-		const window = Deck.from(guest.slice(0, k));
-		const index = startSliding(window, 0);
-		return index;
+		const window = guest.slice(0, k);
+		return startSliding(window, 0);
 	}
 };