import { Meteor } from 'meteor/meteor';

if(Meteor.isServer) {
	WebApp.connectHandlers.use("/reports/AnnualTotals", (req, res, next) => {
		try {
			let result = Meteor.collections.Sales.aggregate([{$group: {_id: {$substr: ['$date', 0, 4]}, total: {$sum: {$multiply: ["$price", "$amount"]}}}}]);
			
			result.toArray().then(function(result) {
				res.writeHead(200, {'Content-Type': 'text/csv'});
				
				res.write("Year,Sales Total\n");
				
				for(let i = 0; i < result.length; i++) {
					res.write(result[i]._id);
					res.write(",");
					res.write("" + result[i].total);
					res.write("\n");
				}
				
				res.end();
			});
		} catch(err) {
			console.log(err);
			res.end();
		}
	});
	WebApp.connectHandlers.use("/reports/MonthlyTotals", (req, res, next) => {
		try {
			let result = Meteor.collections.Sales.aggregate([{$group: {_id: {$substr: ['$date', 0, 6]}, total: {$sum: {$multiply: ["$price", "$amount"]}}}}]);
			
			result.toArray().then(function(result) {
				res.writeHead(200, {'Content-Type': 'text/csv'});
				
				res.write("Date,Sales Total\n");
				
				result.sort(function(a, b) {
					return parseInt(a._id) - parseInt(b._id);
				});
				
				for(let i = 0; i < result.length; i++) {
					res.write(result[i]._id.substr(4, 2) + "/" + result[i]._id.substr(0, 4));
					res.write(",");
					res.write("" + result[i].total);
					res.write("\n");
				}
				
				res.end();
			});
		} catch(err) {
			console.log(err);
			res.end();
		}
	});
	WebApp.connectHandlers.use("/reports/TagTotals", (req, res, next) => {
		try {
			//Aggregate all the sales by product id & year, then later create a map between products and tags to create tag totals.
			let result = Meteor.collections.Sales.aggregate([{
				$group: {
					_id: {$concat: ["$productId", "-", {$substr: ['$date', 0, 4]}]},
					productId: {$first: "$productId"},
					year: {$first: {$substr: ['$date', 0, 4]}},
					total: {$sum: {$multiply: ["$price", "$amount"]}}
				}
			}]);
			
			result.toArray().then(function(result) {
				let productSalesTotalsMapByYear = {};
				
				//Create a map of maps: year -> product id -> sales totals.
				for(let next of result) {
					let productSalesTotalsMap = productSalesTotalsMapByYear[next.year];
					
					//Create the map if necessary.
					if(productSalesTotalsMap === undefined) productSalesTotalsMap = productSalesTotalsMapByYear[next.year] = {};
					
					productSalesTotalsMap[next.productId] = next.total;
				}
				
				//Now create a mapping between the tag id's and tag names for later use.
				let tagIdToTagNameMap = {};
				let tags = Meteor.collections.ProductTags.find({}, {fields: {_id: 1, name: 1}}).fetch();

				for(let tag of tags) {
					tagIdToTagNameMap[tag._id] = tag.name;
				}
				
				//Now create a map between tag names -> [product ids] so that we can build a table below.
				let tagProductIdsMap = {};
				let products = Meteor.collections.Products.find({}, {fields: {_id: 1, tags: 1}}).fetch();
				
				for(let product of products) {
					for(let tagId of product.tags) {
						let tagName = tagIdToTagNameMap[tagId];
						let productIds = tagProductIdsMap[tagName];
						
						//Initialize the array if undefined, and add to the mapping.
						if(productIds === undefined) productIds = tagProductIdsMap[tagName] = [];
						
						productIds.push(product._id);
					}
				}
				
				//Collect the years in ascending oder.
				let years = Object.keys(productSalesTotalsMapByYear).sort(function(a, b) {return parseInt(a) - parseInt(b);});
				
				//Write the response table.
				res.writeHead(200, {'Content-Type': 'text/csv'});
				
				//Start with the table headers:  Tag, Year1, Year2, ..
				res.write("Tag");
				
				//Iterate over the years and add them to the headers.
				for(let year of years) {
					res.write("," + year);
				}
				
				res.write('\n');
				
				//Now write the tag name, and the annual totals for each tag as a row.
				for(let tagName in tagProductIdsMap) {
					let productIds = tagProductIdsMap[tagName];
					
					//console.log(result[i].name + "::" + result[i].total);
					res.write(tagName);
					
					//Iterate over each year to add its total as a column.
					for(let year of years) {
						let productSalesTotalsMap = productSalesTotalsMapByYear[year];
						let annualTotal = 0;
						
						//Iterate over all the product id's for the tag and sum the annual totals for each product that is tagged.
						for(productId of productIds) {
							let productAnnualTotal = productSalesTotalsMap[productId];
							
							if(productAnnualTotal) annualTotal += productAnnualTotal;
						}
						
						res.write("," + annualTotal);
					}
					
					res.write('\n');
				}
				
				res.end();
				
				
				//let tagSalesTotals = [];
				//let tagIdToNameMap = [];
				
				////Find all products and collect sales totals by tag id.
				//let products = Meteor.collections.Products.find({}, {fields: {_id: 1, tags: 1}}).fetch();
				//
				//for(let product of products) {
				//	for(let tag of product.tags) {
				//		let tagSalesTotal = tagSalesTotals[tag];
				//		let productSalesTotal = productSalesTotalsMap[product._id];
				//
				//		if(tagSalesTotal === undefined) tagSalesTotal = 0;
				//		if(productSalesTotal === undefined) productSalesTotal = 0;
				//
				//		tagSalesTotals[tag] = tagSalesTotal + productSalesTotal;
				//	}
				//}
				//
				////Find all tags and convert the tag id's to tag names.
				//let tags = Meteor.collections.ProductTags.find({}, {fields: {_id: 1, name: 1}}).fetch();
				//
				//for(let tag of tags) {
				//	tagIdToNameMap[tag._id] = tag.name;
				//}
				
				////Write the response table.
				//res.writeHead(200, {'Content-Type': 'text/csv'});
				//
				//res.write("Tag,Sales Total\n");
				//
				////result.sort(function(a, b) {
				////	return a.name > b.name ? 1 : -1;
				////});
				//
				//for(let tagId in tagSalesTotals) {
				//	let tagTotal = tagSalesTotals[tagId];
				//	let tagName = tagIdToNameMap[tagId];
				//
				//	//console.log(result[i].name + "::" + result[i].total);
				//	res.write(tagName + ',' + tagTotal + '\n');
				//}
				//
				//res.end();
			}).catch((err) => {
				console.log(err);
				res.end();
			});
			
			//Get all tags
			//Get all products for each tag
			//Total all sales for each product
			//let tags = Meteor.collections.ProductTags.find({},{fields: {_id: 1, name: 1}}).fetch();
			//let result = [];
			//
			//for(let tag of tags) {
			//	let tagTotal = 0;
			//	let products = Meteor.collections.Products.find({tags: tag._id}, {fields: {_id: 1}}).fetch();
			//
			//	for(let product of products) {
			//		let sales = Meteor.collections.Sales.find({productId: product._id}, {fields: {amount: 1, price: 1, _id: 0}}).fetch();
			//
			//		for(let sale of sales) {
			//			tagTotal += sale.amount * sale.price;
			//		}
			//	}
			//
			//	result.push({name: tag.name, total: tagTotal});
			//}
			
			//res.writeHead(200, {'Content-Type': 'text/csv'});
			//
			//res.write("Tag,Sales Total\n");
			//
			//result.sort(function(a, b) {
			//	return a.name > b.name ? 1 : -1;
			//});
			//
			//for(let i = 0; i < result.length; i++) {
			//	console.log(result[i].name + "::" + result[i].total);
			//	res.write(result[i].name);
			//	res.write(",");
			//	res.write("" + result[i].total);
			//	res.write("\n");
			//}
			//
			//res.end();
		} catch(err) {
			console.log(err);
			res.end();
		}
	});
	WebApp.connectHandlers.use("/reports/WeekYearTable", (req, res, next) => {
		try {
			let result = Meteor.collections.Sales.aggregate([{$group: {_id: {$substr: ['$date', 0, 6]}, total: {$sum: {$multiply: ["$price", "$amount"]}}}}]);
			
			result.toArray().then(function(result) {
				res.writeHead(200, {'Content-Type': 'text/csv'});
				
				res.write("Date,Sales Total\n");
				
				result.sort(function(a, b) {
					return parseInt(a._id) - parseInt(b._id);
				});
				
				for(let i = 0; i < result.length; i++) {
					res.write(result[i]._id.substr(4, 2) + "/" + result[i]._id.substr(0, 4));
					res.write(",");
					res.write("" + result[i].total);
					res.write("\n");
				}
				
				res.end();
			});
		} catch(err) {
			console.log(err);
			res.end();
		}
	});
}