var Widget = require('./widget');

module.exports = new Class({
	Extends: Widget
	,Tag: 'htk-grid'
	,Child: 'model'
	,Properties:
	{
		/**
		 * The source data model.
		 */
		model:
		{
			type: Db.Model
			,set: function(x) {
				this.link({_model: x},
				{
					 'status-changed': this.onModelChange
					,'row-deleted': this.onRowDelete
					,'row-updated': this.onRowUpdate
					,'row-inserted': this.onRowInsert
					,'updatable-changed': this.onUpdatableChange
				});

				var set = new Db.SimpleIterator({model: x});
				this.link({_set: set});
				
				this.onUpdatableChange();
				this.onModelChange();
			}
			,get: function() {
				return this._model;
			}
		},
		/**
		 * Message that should be displayed when source model is not ready.
		 */
		emptyMessage:
		{
			type: String
			,value: null
		},
		/**
		 * Wether to display the header with column titles.
		 */
		showHeader:
		{
			type: Boolean
			,set: function(x) {
				this._showHeader = x;
				this.thead.style.display = x ? 'table-header-group' : 'none';
			}
			,get: function() {
				return this._showHeader;
			}
		}
	}

	,_model: null
	,_set: null
	,columns: new Array()
	,internalColumn: null
	,internalColumns: 0
	,sortColumn: -1
	,sortWay: null
	,_showHeader: true
	
	,render: function() {
		var table = this.createRoot('table');
		table.className = 'htk-grid';

		var thead = this.createElement('thead');
		table.appendChild(thead);
		
		this.thead = this.createElement('tr')
		thead.appendChild(this.thead);
		
		this.tbody = this.createElement('tbody');
		table.appendChild(this.tbody);
	}
	
	,appendChild: function(child) {
		this.appendColumn(child);
	}

	,removeClicked: function(column, value, row) {
		if (confirm(_('ReallyDelete')))
			this._model.deleteRow(row);
	}

	,onRowDelete: function(model, row) {
		var tableRows = this.tbody.childNodes;
		this.tbody.removeChild(tableRows[row]);
		
		for (var i = row; i < tableRows.length; i++)
			tableRows[i].className = (i % 2) ? 'pair-row' : '';
	
		this.showNoRecordsFound();
	}

	,onRowInsert: function() {
		this.buildRow(1);
	}

	,renderCell: function(row, column, tr) {
		if (column.columnIndex != -1)
			column.value = this._model.data[row][column.columnIndex];

		if (column.renderer) {
			this._set.row = row;
			column.renderer(column, this._set);
		}

		return column.render(tr);
	}
	
	,refreshRow: function(row, columns) {
		var x = this.columns;
		var tr = this.tbody.childNodes[row];
		
		for (var i = 0; i < x.length; i++)
		if (x[i].renderer || columns.indexOf(x[i].columnIndex) != -1) {
			var cell = this.renderCell(row, x[i], tr);
			tr.replaceChild(cell, tr.childNodes[i]);
		}
	}

	,onRowUpdate: function(model, row, columns) {
		this.refreshRow(row, columns);
	}

	,buildRow: function(count) {
		for (var i = 0; i < count; i++) {
			var tr = this.createElement('tr');
		
			if (i % 2)
				tr.className = 'pair-row';

			for (var j = 0; j < this.columns.length; j++) {
				var cell = this.renderCell(i, this.columns[j], tr);
				tr.appendChild(cell);
			}

			this.tbody.appendChild(tr);
		}
	}

	,onUpdatableChange: function() {
		if (this._model && this._model.updatable) {
			if (!this.internalColumn) {
				this.internalColumn = new Htk.ColumnButton({
					 icon: 'delete'
					,tip: _('Remove')
				});
				this.internalColumn.on('clicked', this.removeClicked, this);
				this.insertInternalColumn(0, this.internalColumn);
			}
		} else if (this.internalColumn) {
			this.internalColumn = null;
			this.removeInternalColumn(0);
		}
	}

	,onModelChange: function() {
		var emptyMessage = this.emptyMessage ?
			this.emptyMessage : _('NoData');
	
		if (!this._model) {
			this.showMessage(emptyMessage, 'refresh');
			return;
		}

		this._node.removeChild(this.tbody);
		this.tbody = this.createElement('tbody');

		switch (this._model.status) {
			case Db.Model.Status.READY:
			{
				for (var i = 0; i < this.columns.length; i++)
					this.columns[i].updateColumnIndex(this._model);
			
				this.buildRow(this._model.numRows);
				this.showNoRecordsFound();
				break;
			}
			case Db.Model.Status.LOADING:
				this.showMessage(_('Loading'), null);
				break;
			case Db.Model.Status.CLEAN:
				this.showMessage(emptyMessage, 'refresh');
				break;
			case Db.Model.Status.ERROR:
				this.showMessage(_('ErrorLoadingData'), 'error');
				break;
		}

		this._node.appendChild(this.tbody);
	}

	,showNoRecordsFound: function() {
		if (this._model.numRows == 0)
			this.showMessage(_('EmptyList'), 'block');
	}

	,showMessage: function(message, src) {
		if (this.columns.length == 0)
			return;
	
		var tr =  this.createElement('tr');
		this.tbody.appendChild(tr);

		var td = this.createElement('td');
		td.className = 'message';
		td.colSpan = this.columns.length;
		tr.appendChild(td);
		
		if (src) {
			const icon = new Htk.Icon({
				name: src
			});
			td.appendChild(icon.node);
		} else {
			var spinner = new Htk.Spinner();
			spinner.start();
			td.appendChild(spinner.node);
		}
		
		var message = this.createTextNode(message);
		td.appendChild(message);
	}
	
	,scrollToRow: function(row) {
		if (row >= 0) {
			var height = parseInt(this.tr.style.height);
			this.node.scrollTop = (row - 2) * height;
		
			if (this.selectedRow)
				this.selectedRow.style.backgroundColor = null;
		
			this.selectedRow = this.tbody.childNodes[row]
			this.selectedRow.style.backgroundColor = '#AAD';
		}
	}

	,sortModel: function(column) {
		var columnIndex = column.columnIndex;

		if (this._model && columnIndex != -1) {
			if (this.sortColumn === columnIndex
			&& this.sortWay === Db.Model.SortWay.ASC)
				this.sortWay = Db.Model.SortWay.DESC;
			else
				this.sortWay = Db.Model.SortWay.ASC;

			this.sortColumn = columnIndex;
		
			this._model.sort(columnIndex, this.sortWay);
		}
	}
	
	,columnChanged: function(column, row, newValue) {
		var columnIndex = column.columnIndex;

		if (columnIndex != -1)
			this._model.setByIndex(row, columnIndex, newValue);
	}
	
	,addColumn: function(pos, column) {
		var header = column.renderHeader();

		if (pos == -1 || pos >= this.columns.length) {
			pos = this.columns.push(column) - 1;
			this.thead.appendChild(header);
		} else {
			this.columns.splice(pos, 0, column);
			this.thead.insertBefore(header, this.thead.childNodes[pos]);
		}

		header.addEventListener('click', 
			this.sortModel.bind(this, column));
		header.title = _('Sort');

		column.on('changed', this.columnChanged, this);
		
		var rows = this.tbody.childNodes;
		
		if (this._model && this._model.numRows > 0)
		for (var i = 0; i < rows.length; i++) {
			var cell = this.renderCell(i, column, rows[i]);
			rows[i].insertBefore(cell, rows[i].childNodes[pos+1]);
		}

		return pos;
	}

	,insertInternalColumn: function(pos, column) {
		if (pos < 0 || pos > this.internalColumns)
			pos = this.internalColumns;

		this.internalColumns++;
		return this.addColumn(pos, column);
	}

	,insertColumn: function(pos, column) {
		if (pos > 0)
			pos += this.internalColumns;

		return this.addColumn(pos, column) - this.internalColumns;
	}

	,appendColumn: function(column) {
		return this.insertColumn(-1, column);
	}

	,deleteColumn: function(pos) {
		if (pos < 0 || pos >= this.columns.length)
			return;

		this.columns.splice(pos, 1);
		this.thead.removeChild(this.thead.childNodes[pos]);
		
		var rows = this.tbody.childNodes;
		
		if (this._model && this._model.numRows > 0)
		for (var i = 0; i < rows.length; i++)
			rows[i].removeChild(rows[i].childNodes[pos]);
	}

	,removeInternalColumn: function(pos) {
		if (this.internalColumns == 0)
			return;
	
		if (pos < 0 || pos > this.internalColumns)
			pos = this.internalColumns;
	
		this.deleteColumn(pos);
		this.internalColumns--;
	}

	,removeColumn: function(pos) {
		if (pos > 0)
			pos += this.internalColumns;
		
		this.deleteColumn(pos);
	}

	,reloadModel: function() {
		if (this._model != null)
			this.onModelChange();
	}
});