From e874ffbfc229d28677b509147e4060e8578510e3 Mon Sep 17 00:00:00 2001
From: Luke Slater <tinmachin3@gmail.com>
Date: Wed, 26 Oct 2011 17:19:52 +0100
Subject: [PATCH] spelling

---
 modules/spelling.js | 39 +++++++++++++++++++++++++++++
 snippets.js         | 60 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 99 insertions(+)
 create mode 100644 modules/spelling.js

diff --git a/modules/spelling.js b/modules/spelling.js
new file mode 100644
index 0000000..ba4b666
--- /dev/null
+++ b/modules/spelling.js
@@ -0,0 +1,39 @@
+var spelling = function(dbot) {
+    var dbot = dbot;
+    var last = {};
+    
+    return {
+        'listener': function(data, params) {
+            var q = data.message.valMatch(/^\*([\d\w\s]*)/, 2);
+            if(q) {
+                var correction = q[1];
+                var candidates = last[data.channel][data.user].split(' ');
+                var winner = false;
+
+                for(int i=0;i<candidates.length;i++) {
+                    var distance = String.prototype.distance(correction, candidates[i]);
+                    if(distance > winner) {
+                        winner = candidates[i];
+                    }
+                }
+                
+                if(winner < 3) {
+                    var fix = data.message.replace(winner, correction); 
+                    dbot.say(data.channel, data.user + ':' + fix);
+                }
+            } else {
+                 if(last.hasOwnProperty(data.channel)) {
+                   last[data.channel][data.user] = data.message; 
+                } else {
+                    last[data.channel] = { };
+                    last[data.channel][data.user] = data.message;
+                }
+            }
+        },
+
+        'on': 'PRIVMSG'
+} 
+
+exports.fetch = function(dbot) {
+    return spelling(dbot);
+};
diff --git a/snippets.js b/snippets.js
index d845ad9..be41eb1 100644
--- a/snippets.js
+++ b/snippets.js
@@ -46,6 +46,66 @@ String.prototype.startsWith = function(needle) {
     return needle === this.slice(0, needle.length);
 };
 
+String.prototype.distance = function(s1, s2) {
+    // Calculate Levenshtein distance between two strings  
+    // 
+    // version: 1109.2015
+    // discuss at: http://phpjs.org/functions/levenshtein    // +            original by: Carlos R. L. Rodrigues (http://www.jsfromhell.com)
+    // +            bugfixed by: Onno Marsman
+    // +             revised by: Andrea Giammarchi (http://webreflection.blogspot.com)
+    // + reimplemented by: Brett Zamir (http://brett-zamir.me)
+    // + reimplemented by: Alexander M Beedie    // *                example 1: levenshtein('Kevin van Zonneveld', 'Kevin van Sommeveld');
+    // *                returns 1: 3
+    if (s1 == s2) {
+        return 0;
+    } 
+    var s1_len = s1.length;
+    var s2_len = s2.length;
+    if (s1_len === 0) {
+        return s2_len;    }
+    if (s2_len === 0) {
+        return s1_len;
+    }
+     // BEGIN STATIC
+    var split = false;
+    try {
+        split = !('0')[0];
+    } catch (e) {        split = true; // Earlier IE may not support access by string index
+    }
+    // END STATIC
+    if (split) {
+        s1 = s1.split('');        s2 = s2.split('');
+    }
+ 
+    var v0 = new Array(s1_len + 1);
+    var v1 = new Array(s1_len + 1); 
+    var s1_idx = 0,
+        s2_idx = 0,
+        cost = 0;
+    for (s1_idx = 0; s1_idx < s1_len + 1; s1_idx++) {        v0[s1_idx] = s1_idx;
+    }
+    var char_s1 = '',
+        char_s2 = '';
+    for (s2_idx = 1; s2_idx <= s2_len; s2_idx++) {        v1[0] = s2_idx;
+        char_s2 = s2[s2_idx - 1];
+ 
+        for (s1_idx = 0; s1_idx < s1_len; s1_idx++) {
+            char_s1 = s1[s1_idx];            cost = (char_s1 == char_s2) ? 0 : 1;
+            var m_min = v0[s1_idx + 1] + 1;
+            var b = v1[s1_idx] + 1;
+            var c = v0[s1_idx] + cost;
+            if (b < m_min) {                m_min = b;
+            }
+            if (c < m_min) {
+                m_min = c;
+            }            v1[s1_idx + 1] = m_min;
+        }
+        var v_tmp = v0;
+        v0 = v1;
+        v1 = v_tmp;    }
+    return v0[s1_len];
+}
+
 /*** Object ***/
 
 Object.prototype.isFunction = function(obj) {