1 files changed, 123 insertions, 0 deletions
diff --git a/lib/logger.js b/lib/logger.js
new file mode 100644
index 0000000..7428180
--- /dev/null
+++ b/lib/logger.js
@@ -0,0 +1,123 @@
+var _ = require('lodash');
+var util = require('util');
+var color = require('bash-color');
+
+var LEVELS = {
+    DEBUG: 0,
+    INFO: 1,
+    WARN: 2,
+    ERROR: 3,
+    DISABLED: 10
+};
+
+var COLORS = {
+    DEBUG: color.purple,
+    INFO: color.cyan,
+    WARN: color.yellow,
+    ERROR: color.red
+};
+
+function Logger(write, logLevel) {
+    if (!(this instanceof Logger)) return new Logger(write, logLevel);
+
+    this._write = write;
+    this.lastChar = '\n';
+
+    // Define log level
+    this.setLevel(logLevel);
+
+    _.bindAll(this);
+
+    // Create easy-to-use method like "logger.debug.ln('....')"
+    _.each(_.omit(LEVELS, 'DISABLED'), function(level, levelKey) {
+        levelKey = levelKey.toLowerCase();
+
+        this[levelKey] = _.partial(this.log, level);
+        this[levelKey].ln = _.partial(this.logLn, level);
+        this[levelKey].ok = _.partial(this.ok, level);
+        this[levelKey].fail = _.partial(this.fail, level);
+        this[levelKey].promise = _.partial(this.promise, level);
+    }, this);
+}
+
+// Change minimum level
+Logger.prototype.setLevel = function(logLevel) {
+    if (_.isString(logLevel)) logLevel = LEVELS[logLevel.toUpperCase()];
+    this.logLevel = logLevel;
+};
+
+// Print a simple string
+Logger.prototype.write = function(msg) {
+    msg = msg.toString();
+    this.lastChar = _.last(msg);
+    return this._write(msg);
+};
+
+// Format a string using the first argument as a printf-like format.
+Logger.prototype.format = function() {
+    return util.format.apply(util, arguments);
+};
+
+// Print a line
+Logger.prototype.writeLn = function(msg) {
+    return this.write((msg || '')+'\n');
+};
+
+// Log/Print a message if level is allowed
+Logger.prototype.log = function(level) {
+    if (level < this.logLevel) return;
+
+    var levelKey = _.findKey(LEVELS, function(v) { return v == level; });
+    var args = Array.prototype.slice.apply(arguments, [1]);
+    var msg = this.format.apply(this, args);
+
+    if (this.lastChar == '\n') {
+        msg = COLORS[levelKey](levelKey.toLowerCase()+':')+' '+msg;
+    }
+
+    return this.write(msg);
+};
+
+// Log/Print a line if level is allowed
+Logger.prototype.logLn = function() {
+    if (this.lastChar != '\n') this.write('\n');
+
+    var args = Array.prototype.slice.apply(arguments);
+    args.push('\n');
+    return this.log.apply(this, args);
+};
+
+// Log a confirmation [OK]
+Logger.prototype.ok = function(level) {
+    var args = Array.prototype.slice.apply(arguments, [1]);
+    var msg = this.format.apply(this, args);
+    if (arguments.length > 1) {
+        this.logLn(level, color.green('>> ') + msg.trim().replace(/\n/g, color.green('\n>> ')));
+    } else {
+        this.log(level, color.green('OK'), '\n');
+    }
+};
+
+// Log a "FAIL"
+Logger.prototype.fail = function(level) {
+    return this.log(level, color.red('ERROR') + '\n');
+};
+
+// Log state of a promise
+Logger.prototype.promise = function(level, p) {
+    var that = this;
+
+    return p.
+    then(function(st) {
+        that.ok(level);
+        return st;
+    }, function(err) {
+        that.fail(level);
+        throw err;
+    });
+};
+
+Logger.LEVELS = LEVELS;
+Logger.COLORS = COLORS;
+
+module.exports =  Logger;