import php.Lib;

enum Maybe<T> {
	Nothing;
	Just(v : T);
}

class QueryIterator<T> {
	var result : Dynamic;
	var nextValue : Maybe<T>;
	public function new(result) {
		this.result= result;
		/* We fetch the first row , so we can answer hasNext */
		fetch();
	}

	private function fetch() {
		var next : Dynamic = untyped __call__('db_fetch', this.result);
		nextValue = if(next) Just(next) else Nothing;
	}

	public function  hasNext() : Bool {
		return this.nextValue != Nothing;
	}

	public function next() : T {
		switch(this.nextValue) {
		case Nothing : throw 'Iterator exhausted';
		case Just(v) :  {
			this.fetch();
			return v;
		};
		}
	}
}
class FA {
	static public function query(sql: String) {
		var result = untyped __call__('db_query', sql, sql);
		return new QueryIterator(result);
	}

	static public function tb() : String {
		return untyped __php__('TB_PREF');
	}

	static public function sql2date(sqlDate:Dynamic) : Null<Date> {
		return sqlDate == null ? null : Date.fromString(sqlDate);
	}
}
class ItemScheduler {
	var stock_id:String;
	var startLocation:String;
	var qoh: Int;
	function new(stock_id: String, startLocation) {
		this.stock_id = stock_id;
		this.startLocation = startLocation;
		qoh =  untyped __call__('get_qoh_on_date', this.stock_id, 'DEF');
	}

	function tableHeader() {
		return ["Order", "Customer", "Quantity", "Before", "After", "Loc", "From",  "Required Date", "Comment"];
	}

/*
	function generateTablex(): Void {
		for(location in locations()) {
			formatLocation(location, null);
		}
		for(order in this.orders()) {
			this.formatRow(order);
		}
	}
*/

	function generateTable(): Void {
			var startDate = Date.fromTime(0);
			for(order in orders()) {
					var obj = php.Lib.objectOfAssociativeArray(order);

			}	

			// Sort location by datae
			var locations = this.locations();
			locations.sort(function(a, b) {
				return cast(a.delivery.getTime() - b.delivery.getTime(), Int );
				});

		// Get the start location, it should be the first one
		var locationIter = locations.iterator();
		var location  = locationIter.next();
		var qoh : Int = location.quantityOnHand(stock_id, null);
		var left = qoh;
		formatLocation(location, "Initial", left);

		// We display the order ordered by priority 
		// But insert the location when needed (meaning
		// when we run out of item available
		for(orderRow in orders()) {
			var order = php.Lib.objectOfAssociativeArray(orderRow);
			var quantity : Int = Std.parseInt(order.quantity);

			while(0 > left && locationIter.hasNext()) {
				location = locationIter.next();
				var quantityForLocation : Int = location.quantityOnHand(stock_id, null);
				if(quantityForLocation == null || quantityForLocation == 0) continue;
				left += quantityForLocation;
				formatLocation(location, "Delivery", left);
			}
			left -= quantity;

			formatOrder(order, left, location.delivery);
			
		}
			
	}

	function printRow(tds : Array<Dynamic>, attributes : Array<String>) {
		php.Lib.print('<tr '+attributes.join(' ')+'>');
		for(td in tds) {
			php.Lib.print('<td>');
			if(td) php.Lib.print(td);
			php.Lib.print('</td>');
		}
		php.Lib.print('</tr>');
	}

	function formatOrder(order : Dynamic, left : Int, date : Date) {
			var attributes = [];
			var classes = [];
			var before : Int = left + order.quantity;
			/* We have basically 3 different cases;
			 * - the order can be fullfilled
			 * - the order can be partially 
		   * - not at all
			 */
			if (before < 0 ) {
					classes.push('soldout');
			}
			else if(left < 0) {
					classes.push('partial');
			}
			else {
					classes.push('full');
			}

			/* The order can also be late if we need
			 * to wait for a delivery to get it
			 */
		var required_by : Date = FA.sql2date(order.required_date);
		if(required_by == null) required_by = FA.sql2date(order.delivery_date);
		if(required_by.getTime() < date.getTime()) {
			classes.push('late');
		}
		else {
			classes.push('on_time');
		}
			var cells : Array <Dynamic> = [
				order.order_id
				, '<a href="/modules/order_line_extra/order_lines_view.php?customer_id='+Std.string(order.debtor_no)+'">'+order.deliver_to+'</a>'
				,order.quantity
				,before
				,left
				,order.from_stk_loc
				,order.delivery_date
				,order.required_date 
				,order.comment
			];

			attributes.push('class="'+classes.join(' ')+'"');
			printRow(cells, attributes);

	}

	function formatRow(row) {
		var array = php.Lib.hashOfAssociativeArray(row);
		var quantity_before : Int = array.get('quantity_before');
		var quantity_available = qoh - quantity_before;
		var quantity: Int = array.get('quantity');

		var status : String = if(quantity_available < quantity) 'overduebg';

		var cells : Array<Dynamic> = [
			array.get('order_id')
			,array.get('deliver_to')
			,quantity
			,quantity_available-quantity
			,quantity_available
			,array.get('from_stk_loc')
			,array.get('delivery_date')
		];

		php.Lib.print('<tr class="'+status+'">');
		for(cell in cells) {
			php.Lib.print('<td>');
			php.Lib.print(cell);
			php.Lib.print('</td>');
		}
		php.Lib.print('</tr>');
		
		
	}

	function formatLocation(location : Location, type: String,  left : Int) {
		var cells = [
			type
			,location.name
			,location.quantityOnHand(stock_id, null)
			,left-location.quantityOnHand(stock_id, null)
			,left
			,location.code
			,location.delivery
			,""
			,""
		];

		printRow(cells, ['class = "tableheader location"']);
	}

/*
	function schedules() {
		//return orders()+locations();
		//return  orders();
		return cast(locations(), Array<Dynamic>);

	}
*/

	function orders() {
		var tb : String =  untyped __php__('TB_PREF');
		var sql : String = "SELECT *  
						FROM "+tb+"denorm_order_details_queue  d
						JOIN "+tb+"sales_order_details od ON (od.id = d.id)
						JOIN "+tb+"sales_orders so ON (so.order_no = d.order_id)
						WHERE stock_id = '"+this.stock_id+"'
						AND od.trans_type = 30
						ORDER by quantity_before";
	
		return FA.query(sql);
	}

	function locations() {
		var TB = FA.tb();
		var sql = 'SELECT * 
							FROM '+TB+'locations';
		var _locs = [];
		for(row in FA.query(sql)) {
			var location = new Location(row);
			if(location.code == startLocation) {
			 location.delivery =  Date.fromTime(0);
			}
			_locs.push(location);
		}

		return _locs;
		
	}


	function purcharseOrders()  {
	}

}