/* global $, hljs, window, document */

///// represents a single document

let haste_document = function(){
	this.locked = false;
};

// Escapes HTML tag characters
haste_document.prototype.htmlEscape = function(s){
	return s
		.replace(/&/g, '&')
		.replace(/>/g, '>')
		.replace(/</g, '&lt;')
		.replace(/"/g, '&quot;');
};

// Get this document from the server and lock it here
haste_document.prototype.load = function(key, callback, lang){
	let _this = this;
	$.ajax(`/documents/${key}`, {
		type: 'get',
		dataType: 'json',
		success: function(res){
			_this.locked = true;
			_this.key = key;
			_this.data = res.data;
			let high;
			try {
				if (lang == 'txt'){
				high = { value: _this.htmlEscape(res.data) };
				}
				else if (lang){
				high = hljs.highlight(lang, res.data);
				}
				else {
				high = hljs.highlightAuto(res.data);
				}
			}
			catch(err){
				// failed highlight, fall back on auto
				high = hljs.highlightAuto(res.data);
			}
			callback({
				value: high.value,
				key: key,
				language: high.language || lang,
				lineCount: res.data.split('\n').length
			});
		},
		error: function(){
			callback(false);
		}
	});
};

// Save this document to the server and lock it here
haste_document.prototype.save = function(data, callback){
	if (this.locked) return false;
	this.data = data;
	let _this = this;
	$.ajax('/documents', {
		type: 'post',
		data: data,
		dataType: 'json',
		contentType: 'application/json; charset=utf-8',
		success: function(res){
			_this.locked = true;
			_this.key = res.key;
			let high = hljs.highlightAuto(data);
				callback(null, {
				value: high.value,
				key: res.key,
				language: high.language,
				lineCount: data.split('\n').length
			});
		},
		error: function(res){
			try {
				callback($.parseJSON(res.responseText));
			}
			catch (e){
				callback({message: 'Something went wrong!'});
			}
		}
	});
};

///// represents the paste application

let haste = function(appName, options){
	this.appName = appName;
	this.$textarea = $('textarea');
	this.$box = $('#box');
	this.$code = $('#box code');
	this.$linenos = $('#linenos');
	this.options = options;
	this.configureShortcuts();
	this.configureButtons();
	// If twitter is disabled, hide the button
	if (!options.twitter) $('#box2 .twitter').hide();
};

// Set the page title - include the appName
haste.prototype.setTitle = function(ext){
	document.title = `${this.appName}${ext ? ` - ${ext}` : ''}`;
};

// Show a message box
haste.prototype.showMessage = function(msg, cls){
	let msgBox = $(`<li class="${cls || 'info'}">${msg}</li>`);
	$('#messages').prepend(msgBox);
	setTimeout(function(){
		msgBox.slideUp('fast', function(){ $(this).remove(); });
	}, 3000);
};

// Show the light key
haste.prototype.lightKey = function(){
	this.configureKey(['new', 'save']);
};

// Show the full key
haste.prototype.fullKey = function(){
	this.configureKey(['new', 'duplicate', 'twitter', 'raw']);
};

// Set the key up for certain things to be enabled
haste.prototype.configureKey = enable => {
	let $this;
	$('#box2 .function').each(function(){
		$this = $(this);
		for (el of enable){
			if ($this.hasClass(el)){
				$this.addClass('enabled');
				return true;
			}
		}
		$this.removeClass('enabled');
	});
};

// Remove the current document (if there is one)
// and set up for a new one
haste.prototype.newDocument = function(hideHistory){
	this.$box.hide();
	this.doc = new haste_document();
	if (!hideHistory){
		window.history.pushState(null, this.appName, '/');
	}
	this.setTitle();
	this.lightKey();
	this.$textarea.val('').show('fast', function(){
		this.focus();
	});
	this.removeLineNumbers();
};

// Map of common extensions
// Note: this list does not need to include anything that IS its extension,
// due to the behavior of lookupTypeByExtension and lookupExtensionByType
// Note: optimized for lookupTypeByExtension
haste.extensionMap = {
	rb: 'ruby', py: 'python', pl: 'perl', php: 'php', scala: 'scala', go: 'go',
	xml: 'xml', html: 'xml', htm: 'xml', css: 'css', js: 'javascript', vbs: 'vbscript',
	lua: 'lua', pas: 'delphi', java: 'java', cpp: 'cpp', cc: 'cpp', m: 'objectivec',
	vala: 'vala', sql: 'sql', sm: 'smalltalk', lisp: 'lisp', ini: 'ini',
	diff: 'diff', bash: 'bash', sh: 'bash', tex: 'tex', erl: 'erlang', hs: 'haskell',
	md: 'markdown', txt: '', coffee: 'coffee', json: 'javascript',
	swift: 'swift'
};

// Look up the extension preferred for a type
// If not found, return the type itself - which we'll place as the extension
haste.prototype.lookupExtensionByType = function(type){
	for (let key in haste.extensionMap){
		if (haste.extensionMap[key] == type) return key;
	}
	return type;
};

// Look up the type for a given extension
// If not found, return the extension - which we'll attempt to use as the type
haste.prototype.lookupTypeByExtension = function(ext){
	return haste.extensionMap[ext] || ext;
};

// Add line numbers to the document
// For the specified number of lines
haste.prototype.addLineNumbers = function(lineCount){
	let h = '';
	for (let i = 0; i < lineCount; i++){
		h += (i + 1).toString() + '<br/>';
	}
	$('#linenos').html(h);
};

// Remove the line numbers
haste.prototype.removeLineNumbers = function(){
	$('#linenos').html('&gt;');
};

// Load a document and show it
haste.prototype.loadDocument = function(key){
	// Split the key up
	let parts = key.split('.', 2);
	// Ask for what we want
	let _this = this;
	_this.doc = new haste_document();
	_this.doc.load(parts[0], function(ret){
		if (ret){
			_this.$code.html(ret.value);
			_this.setTitle(ret.key);
			_this.fullKey();
			_this.$textarea.val('').hide();
			_this.$box.show().focus();
			_this.addLineNumbers(ret.lineCount);
		}
		else {
			_this.newDocument();
		}
	}, this.lookupTypeByExtension(parts[1]));
};

// Duplicate the current document - only if locked
haste.prototype.duplicateDocument = function(){
	if (this.doc.locked){
		let currentData = this.doc.data;
		this.newDocument();
		this.$textarea.val(currentData);
	}
};

// Lock the current document
haste.prototype.lockDocument = function(){
	let _this = this;
	this.doc.save(this.$textarea.val(), function(err, ret){
		if (err){
			_this.showMessage(err.message, 'error');
		}
		else if (ret){
			_this.$code.html(ret.value);
			_this.setTitle(ret.key);
			let file = `/${ret.key}`;
			if (ret.language){
				file += `.${_this.lookupExtensionByType(ret.language)}`;
			}
			window.history.pushState(null, `${_this.appName}-${ret.key}`, file);
			_this.fullKey();
			_this.$textarea.val('').hide();
			_this.$box.show().focus();
			_this.addLineNumbers(ret.lineCount);
		}
	});
};

haste.prototype.configureButtons = function(){
	let _this = this;
	this.buttons = [
		{
			$where: $('#box2 .save'),
			label: 'Save',
			shortcutDescription: 'control + s',
			shortcut: function(evt){
				return evt.ctrlKey && (evt.keyCode == 83);
			},
			action: function(){
				if (_this.$textarea.val().replace(/^\s+|\s+$/g, '') != ''){
					_this.lockDocument();
				}
			}
		},
		{
			$where: $('#box2 .new'),
			label: 'New',
			shortcut: function(evt){
				return evt.ctrlKey && evt.keyCode == 78;
			},
			shortcutDescription: 'control + n',
			action: function(){
				_this.newDocument(!_this.doc.key);
			}
		},
		{
			$where: $('#box2 .duplicate'),
			label: 'Duplicate & Edit',
			shortcut: function(evt){
				return _this.doc.locked && evt.ctrlKey && evt.keyCode == 68;
			},
			shortcutDescription: 'control + d',
			action: function(){
				_this.duplicateDocument();
			}
		},
		{
			$where: $('#box2 .raw'),
			label: 'Just Text',
			shortcut: function(evt){
				return evt.ctrlKey && evt.shiftKey && evt.keyCode == 82;
			},
			shortcutDescription: 'control + shift + r',
			action: function(){
				window.location.href = `/raw/${_this.doc.key}`;
			}
		},
		{
			$where: $('#box2 .twitter'),
			label: 'Twitter',
			shortcut: function(evt){
				return _this.options.twitter && _this.doc.locked && evt.shiftKey && evt.ctrlKey && evt.keyCode == 84;
			},
			shortcutDescription: 'control + shift + t',
			action: function(){
				window.open(`https://twitter.com/share?url=${encodeURI(window.location.href)}`);
			}
		}
	];
	for (button of this.buttons){
		this.configureButton(button);
	}
};

haste.prototype.configureButton = function(options){
	// Handle the click action
	options.$where.click(function(evt){
		evt.preventDefault();
		if (!options.clickDisabled && $(this).hasClass('enabled')){
			options.action();
		}
	});
	// Show the label
	options.$where.mouseenter(function(){
		$('#box3 .label').text(options.label);
		$('#box3 .shortcut').text(options.shortcutDescription || '');
		$('#box3').show();
		$(this).append($('#pointer').remove().show());
	});
	// Hide the label
	options.$where.mouseleave(function(){
		$('#box3').hide();
		$('#pointer').hide();
	});
};

// Configure keyboard shortcuts for the textarea
haste.prototype.configureShortcuts = function(){
	let _this = this;
	$(document.body).keydown(function(evt){
		for (button of _this.buttons){
			if (button.shortcut && button.shortcut(evt)){
				evt.preventDefault();
				button.action();
				return;
			}
		}
	});
};

///// Tab behavior in the textarea - 2 spaces per tab
$(function(){
	$('textarea').keydown(function(evt){
		if (evt.keyCode == 9){
			evt.preventDefault();
			let myValue = '  ';
			// http://stackoverflow.com/questions/946534/insert-text-into-textarea-with-jquery
			// For browsers like Internet Explorer
			if (document.selection){
				this.focus();
				let sel = document.selection.createRange();
				sel.text = myValue;
				this.focus();
			}
			// Mozilla and Webkit
			else if (this.selectionStart || this.selectionStart == '0'){
				let startPos = this.selectionStart;
				let endPos = this.selectionEnd;
				let scrollTop = this.scrollTop;
				this.value = this.value.substring(0, startPos) + myValue +
					this.value.substring(endPos,this.value.length);
				this.focus();
				this.selectionStart = startPos + myValue.length;
				this.selectionEnd = startPos + myValue.length;
				this.scrollTop = scrollTop;
			}
			else {
				this.value += myValue;
				this.focus();
			}
		}
	});
});