/*
 * DDL Builder
 * Copyright Jake Feasel, 2012
 * Released under MIT license
 * For questions email admin at sqlfiddle dot com
 * http://github.com/jakefeasel/DDLBuilder
 */

define(
	[
	 "jQuery", 
	 "Handlebars", 
	 "DateFormat", 
	 'text!./templates/generic.sql',
	 'text!./templates/oracle.sql',
	 'text!./templates/sqlite.sql',
	 'HandlebarsHelpers/each_with_index'
	 ],
	function ($, Handlebars, dateFormat, generic_template, oracle_template, sqlite_template) {

	ddl_builder = function (args) {
		if (!args) args = {};
		// output settings
		this.fieldPrefix = '';
		this.fieldSuffix = '';
		this.tablePrefix = '';
		this.tableSuffix = '';


		this.dateFormatMask = "yyyy-mm-dd HH:MM:ss";
		
		this.charType = 'varchar';
		this.intType = 'int';
		this.floatType = 'numeric';
		this.dateType = 'datetime';
		
		// input settings
		this.valueSeparator = '';

		this.column_count = 0;
		this.definition = { 
				tableName: "Table1",
				columns: [/* sample column structure
							{
								name: 'id',
								type: 'int',
								length: '',
								db_type: 'int4'
							},
							{
								name: 'name',
								type: 'char',
								length: 20,
								db_type: 'varchar(20)'
							}					
				 			*/],
				data: [/* sample data structure
							 // r for "row", v for "value"
							{r:[{v:1},{v:'Jake'}]},
							{r:[{v:2},{v:'Rachel'}]},
							{r:[{v:3},{v:'Andrew'}]},
							{r:[{v:4},{v:'Ada'}]},
							{r:[{v:5},{v:'Lucy O\'Malley'}]}
				
				
				 		*/]
			};

		
		this.ddlTemplate = generic_template;

		this.compiledTemplate = Handlebars.compile(this.ddlTemplate);
		this.setup(args);
		return this;
	};
	
	ddl_builder.prototype.setup = function (settings) {
		for (var opt in settings)
		{
			this[opt] = settings[opt];
		}
		
		if (settings["ddlTemplate"])
			this.compiledTemplate = Handlebars.compile(this.ddlTemplate);
		
		if (settings["tableName"])
			this.definition.tableName = settings.tableName;
		
		return this;
	};
	
	ddl_builder.prototype.setupForDBType = function (type,separator) {
		
		switch (type)
		{
			case 'SQL Server':
				this.setup({
								statement_separator: separator,
								fieldPrefix: '[',
								fieldSuffix: ']',
								tablePrefix: '[',
								tableSuffix: ']'
							});	
			break;

			case 'MySQL':
				this.setup({ 
								statement_separator: separator,
								fieldPrefix: '`',
								fieldSuffix: '`',
								tablePrefix: '`',
								tableSuffix: '`'
							});	
			break;
			case 'PostgreSQL':
				this.setup({ 
								statement_separator: separator,
								dateType: 'timestamp',
								fieldPrefix: '"',
								fieldSuffix: '"'
							});	
			break;

			case 'Oracle':	
				var template = oracle_template;
												
					this.setup({ 
								dateFormatMask: 'dd-mmm-yyyy hh:MM:ss TT',
								statement_separator: separator,
								ddlTemplate: template,
								dateType: 'timestamp',
								charType: 'varchar2',
								fieldPrefix: '"',
								fieldSuffix: '"'
							});	
			break;



			case 'SQLite':	
				var template = sqlite_template;

												
					this.setup({ 
								fieldPrefix: '"',
								fieldSuffix: '"',
								tablePrefix: '"',
								tableSuffix: '"',
								statement_separator: separator,
								ddlTemplate: template,
								dateType: 'DATE',
								charType: 'TEXT',
								intType: 'INTEGER',
								floatType: 'REAL'
							});	
			break;


		}
		return this;
	};
	
	ddl_builder.prototype.populateDBTypes = function () {
		for (var i=0;i<this.definition.columns.length;i++)
		{
			if (this.definition.columns[i].type == 'charType')
				this.definition.columns[i].db_type = this[this.definition.columns[i].type] + "(" + this.definition.columns[i].length + ")";
			else	
				this.definition.columns[i].db_type = this[this.definition.columns[i].type];
		}
		
		this.definition.dateFormatMask = this.dateFormatMask;
		
	};
	
	ddl_builder.prototype.populateWrappers = function () {
		this.definition.fieldPrefix = this.fieldPrefix;
		this.definition.fieldSuffix = this.fieldSuffix;
	};
	
	
	ddl_builder.prototype.guessValueSeparator = function (raw) {
		

		var lines = raw.split("\n");
		var header_found = false, column_count = 0, found_separator = '';
		
		for (var i = 0; i<lines.length; i++)
		{
			if (lines[i].search(/[A-Z0-9_]/i) != -1 && !header_found) // if this line contains letters/numbers/underscores, then we can assume we've hit the header row 
			{
				var chunks = $.trim(lines[i]).match(/([A-Z0-9_]+ ?)+([^A-Z0-9_]*)/gi);
				if (chunks.length == 1)
				{
					chunks = $.trim(lines[i]).match(/([A-Z0-9_]+ ?)+?([^A-Z0-9_]*)/gi);
				}
				
				header_found = true;
				
				for (var j = 0; j < chunks.length; j++)
				{
					var this_separator = chunks[j].match(/[A-Z0-9_]+([^A-Z0-9_]*)$/i).pop(); // gets the last returned value from regexp
					
					if (this_separator.search(/^\s\s+$/) != -1)
						this_separator = new RegExp("\\s\\s+");
					else if (this_separator.search(/^\t+$/) != -1)
						this_separator = new RegExp("\\t+");
					else if (this_separator.search(/^\s+$/) != -1)
						this_separator = new RegExp("\\s+");
					else
						this_separator = $.trim(this_separator);

					if (this_separator instanceof RegExp || this_separator.length)
					{
						if (!(found_separator instanceof RegExp) && !found_separator.length)
							found_separator = this_separator;
						else if (found_separator.toString() != this_separator.toString())
							return {status: false, message: 'Unable to find consistent column separator in header row'}; // different separators founds?
					}
					else if (! (this_separator instanceof RegExp) && !(found_separator instanceof RegExp) && !found_separator.length)	
					{
						found_separator = "\n";
					}
					
				}
				if (found_separator instanceof RegExp || found_separator.length)
					column_count = $.trim(lines[i]).split(found_separator).length;
				else
					column_count = 1;
				
				
			}
			else if (lines[i].search(/[A-Z0-9_]/i) != -1)
			{
				if ($.trim(lines[i]).split(found_separator).length != column_count && 
						(
								found_separator.toString() != /\s\s+/.toString() ||
								$.trim(lines[i]).split(/\s+/).length != column_count
						)
					)
					return {status: false, message: 'Line ' + i + ' does not have the same number of columns as the header, based on separator "' + found_separator + '".'};
			
			}
		
		}
		return {status: true, separator: found_separator, column_count: column_count};
	};
	
	ddl_builder.prototype.parse = function (raw) {

		/* 
		 * brokenDateChecker is used to eliminate strings that for some reason pass Chrome's standard of a 'valid' date, and
		 * yet are not worth considering as such. Chrome will take garbage like 'ABC 1' as an input to `new Date()`, returning
		 * January 1st 2001 for some reason.  This regex will allow a lot of fuzzy input formats to still pass, but only really 
		 * keep meaningful entries. This isn't a problem for Firefox or Safari. I haven't checked IE.
		 */ 
		var brokenDateChecker = /^(?!Jan)(?!Feb)(?!Mar)(?!Apr)(?!May)(?!Jun)(?!Jul)(?!Aug)(?!Sep)(?!Oct)(?!Nov)(?!Dec)[A-Za-z\ \-\_]+\d+\s*$/,
			result = {}, lines = [], elements = [], tmpRow = [], i = 0, j = 0, value = "";

		if (!this.valueSeparator.length)
		{	
			result = this.guessValueSeparator(raw);
			if (!result.status)
				return "ERROR! " + result.message;
			else
			{
				this.column_count = result.column_count;
				this.valueSeparator = result.separator;
			}
		}
		
		lines = raw.split("\n");
		
		for (i=0;i<lines.length;i++)
		{
			elements = $.trim(lines[i]).split(this.valueSeparator);

			if ($.trim(lines[i]).length && 
					(
						elements.length == this.column_count ||
						(
								this.valueSeparator.toString() == /\s\s+/.toString() &&
								(elements =  $.trim(lines[i]).split(/\s+/)).length == this.column_count
						)
					)
				)
			{
				if (! this.definition.columns.length)
				{	
					for (j = 0; j < elements.length; j++)
					{	
							value = $.trim(elements[j]);
							if (value.length)
								this.definition.columns.push({"name": value});
							else
								this.definition.columns.push(false);
					}
				}
				else
				{
					tmpRow = [];
					for (j = 0; j < elements.length; j++)
					{
						if (this.definition.columns[j] !== false)
						{
							value = $.trim(elements[j]).replace(/'/g, "''");
	
							// if the current field is not a number, or if we have previously decided that this one of the non-numeric field types...
							if (isNaN(value) || this.definition.columns[j].type == 'dateType' || this.definition.columns[j].type == 'charType')
							{
								
								// if we haven't previously decided that this is a character field, and it can be cast as a date, then declare it a date 
								if (this.definition.columns[j].type != 'charType' && !(isNaN(Date.parse("UTC:" + value)) || value.match(brokenDateChecker)) ) 
									this.definition.columns[j].type = "dateType";
								else
									this.definition.columns[j].type = "charType";
							}
							else // this must be some kind of number field
							{
								if (this.definition.columns[j].type != 'floatType' && value % 1 != 0)
									this.definition.columns[j].type = 'floatType';
								else
									this.definition.columns[j].type = 'intType';
							}
							
							if (!this.definition.columns[j].length || value.length > this.definition.columns[j].length)
							{
								this.definition.columns[j].length = value.length;
							}
							
							tmpRow.push({v:value});
						}
							
					}
					this.definition.data.push({r: tmpRow});
				
				}
					
			}
		}
		this.populateDBTypes();
		this.populateWrappers();
		return this.render();		
	};

	/* HandlebarsJS-using code below */
	
	Handlebars.registerHelper("formatted_field", function(root) {
	
		var colType = '';
		var index = -1;
		for (var j = 0; j < root.columns.length; j++)
		{
			if (root.columns[j])
				index++;
				
			if (index == this.index)
			{
				colType = root.columns[j].type;
				break;
			}
		}
		
		
		if (!this.v.length || this.v.toUpperCase() == 'NULL')
			return 'NULL';
		if (colType == 'charType')
			return new Handlebars.SafeString("'" + this.v + "'");
		
		if (colType == 'dateType') {
			return new Handlebars.SafeString("'" + dateFormat("UTC:" + this.v, root.dateFormatMask) + "'");
		}
		
		return this.v;
	});
	
	Handlebars.registerHelper("column_name_for_index", function(root) {		
		return root.columns[this.index].name;
	});
	
	
	ddl_builder.prototype.render = function () {
		return this.compiledTemplate($.extend(this.definition, {"separator": this.statement_separator}));		
	};
	
	return ddl_builder;
	
});