var fs = require("fs");
var csv = require('./csv.js');
var Promise = require('bluebird');

var fileName = "./importItems.csv";

// module.exports = function(models, softErrors) {
// 	return new Promise(function(resolve, reject) {
var models = require("./models");
var softErrors = [];
var p = new Promise(function(resolve, reject) {
		//var sequelize = models.sequelize;
		//The CSV data as an array of rows (each row is an array).
		var data;
		//The mapping of model attributes to CSV columns.  The oz sizes are arrays of columns since there are multiple.
		var map = {};
		//The id's in the db for the various jar sizes.
		var measureIdMap = {};
		//The id of the 'each' measure.
		var eachId = -1;
		//A default price for all items.
		var DEFAULT_PRICE = 11.0;

		//Collect the metadata from the first row of the CSV data - make a mapping.
		function collectMetadata() {
			var CATEGORY = 'category';
			var SUBCATEGORY = 'subcategory';
			var ITEM = 'item';
			var OZ32 = '32 oz';
			var OZ16 = '16 oz';
			var OZ12 = '12 oz';
			var OZ8 = '8 oz';
			var OZ4 = '4 oz';

			//Data is an array of arrays.  data[0] = array of headers.  data[1] = first row of data.
			//Iterate over the columns to create a mapping.
			for(var i = 0; i < data[0].length; i++) {
				var next = data[0][i];

				if(next && next != '') {
					switch(next.toLowerCase()) {
						case CATEGORY:
							map.category = i;
							break;
						case SUBCATEGORY:
							map.subcategory = i;
							break;
						case ITEM:
							map.item = i;
							break;
						case OZ32:
							if(!map.oz32) map.oz32 = [];
							map.oz32.push(i);
							break;
						case OZ16:
							if(!map.oz16) map.oz16 = [];
							map.oz16.push(i);
							break;
						case OZ12:
							if(!map.oz12) map.oz12 = [];
							map.oz12.push(i);
							break;
						case OZ8:
							if(!map.oz8) map.oz8 = [];
							map.oz8.push(i);
							break;
						case OZ4:
							if(!map.oz4) map.oz4 = [];
							map.oz4.push(i);
							break;
					}
				}
			}
		}

		//Reads a single row of CSV data and adds it to the database.
		function readRow(rowIndex) {
			if(!data) {
				console.log("WTF?");
				//process.exit(1);
				reject(new Error("Data is null?!?"));
				return;
			}
			else if(!data[rowIndex]) {
				softErrors.push("Empty line? - Found while reading items.");
				readRow(rowIndex + 1);
				return;
			}

			var category = data[rowIndex][map.category];
			var subcategory = data[rowIndex][map.subcategory];
			var item = data[rowIndex][map.item];
			var oz32 = 0;
			var oz16 = 0;
			var oz12 = 0;
			var oz8 = 0;
			var oz4 = 0;

			for(var o = 0; o < map.oz32.length; o++) {
				oz32 += Math.max(data[rowIndex][map.oz32[o]], 0);
			}

			for(var o = 0; o < map.oz16.length; o++) {
				oz16 += Math.max(data[rowIndex][map.oz16[o]], 0);
			}

			for(var o = 0; o < map.oz12.length; o++) {
				oz12 += Math.max(data[rowIndex][map.oz12[o]], 0);
			}

			for(var o = 0; o < map.oz8.length; o++) {
				oz8 += Math.max(data[rowIndex][map.oz8[o]], 0);
			}

			for(var o = 0; o < map.oz4.length; o++) {
				oz4 += Math.max(data[rowIndex][map.oz4[o]], 0);
			}

			//If the category doesn't yet exist then add it, otherwise get the ID.
			models.Category.findOrCreate({where: {name: category}, defaults: {name: category}}).then(function(result) {
				var categoryId = result[0].id;  //Note: result[1] is a boolean indicating whether the object had to be created.

				//If the subcategory doesn't yet exist then add it, otherwise get the ID.
				models.Subcategory.findOrCreate({
					where: {name: subcategory},
					defaults: {name: subcategory, categoryId: categoryId}
				}).then(function(result) {
					var subcategoryId = result[0].id;
					var weightedMeasures = [];
					var measures = [];

					if(oz32 > 0) weightedMeasures.push({name: '32 oz', count: oz32});
					if(oz16 > 0) weightedMeasures.push({name: '16 oz', count: oz16});
					if(oz12 > 0) weightedMeasures.push({name: '12 oz', count: oz12});
					if(oz8 > 0) weightedMeasures.push({name: '8 oz', count: oz8});
					if(oz4 > 0) weightedMeasures.push({name: '4 oz', count: oz4});

					if(weightedMeasures.length == 0) {
						measures.push(eachId);
					}
					else {
						//Place the measure that had the most jars at the front of the list.
						weightedMeasures.sort(function(a, b) {
							return a.count >= b.count ? 1 : -1;
						});

						//Build the array of measure id's.
						for(var i = 0; i < weightedMeasures.length; i++) {
							measures.push(measureIdMap[weightedMeasures[i].name]);
						}
					}

					//Ensure the item doesn't yet exist - display an error if it does, otherwise add it.
					models.Item.findOrCreate({
						where: {name: item},
						defaults: {name: item, subcategoryId: subcategoryId, measures: measures}
					}).then(function(result) {
						if(!result[1]) {
							console.log("The item named '" + item + "' already exists in the database.");
						}

						//Recursively read rows until there are no more rows to read.
						if(rowIndex + 1 < data.length) readRow(rowIndex + 1);
						else resolve();
					});
				})
			});
		}

		if(fs.existsSync(fileName)) {
			csv.read(fileName, function(error, csvData) {
				if(error) console.log(error);
				else {
					data = csvData;
					//Collect the mapping data.
					collectMetadata();

					//Read or create the required models to make this all work:
					Promise.each([
						models.Measure.findOrCreate({where: {name: 'Jar 32oz'}, defaults: {name: 'Jar 32oz', postfix: '32oz'}}),
						models.Measure.findOrCreate({where: {name: 'Jar 16oz'}, defaults: {name: 'Jar 16oz', postfix: '16oz'}}),
						models.Measure.findOrCreate({where: {name: 'Jar 12oz'}, defaults: {name: 'Jar 12oz', postfix: '12oz'}}),
						models.Measure.findOrCreate({where: {name: 'Jar 8oz'}, defaults: {name: 'Jar 8oz', postfix: '8oz'}}),
						models.Measure.findOrCreate({where: {name: 'Jar 4oz'}, defaults: {name: 'Jar 4oz', postfix: '4oz'}}),
						models.Measure.findOrCreate({where: {name: 'Each'}, defaults: {name: 'Each', postfix: ''}})
					], function(value, index, length) {
						switch(index) {
							case 0:
								measureIdMap['32 oz'] = value[0].id;
								break;
							case 1:
								measureIdMap['16 oz'] = value[0].id;
								break;
							case 2:
								measureIdMap['12 oz'] = value[0].id;
								break;
							case 3:
								measureIdMap['8 oz'] = value[0].id;
								break;
							case 4:
								measureIdMap['4 oz'] = value[0].id;
								break;
							case 5:
								eachId = value[0].id;
								break;
						}
					}).then(function() {
						//Read the first row.
						readRow(1);
					});
				}
			});
		}
		else {
			console.log("Cannot find " + fileName);
		}
});

p.then(function() {console.log("Import Complete!")}).error(function(error) {console.log("Ran into an error: \n" + error)});
// };