openmct/platform/features/table/src/controllers/MCTTableController.js
2016-05-25 13:23:19 -07:00

520 lines
19 KiB
JavaScript

define(
[],
function () {
/**
* A controller for the MCTTable directive. Populates scope with
* data used for populating, sorting, and filtering
* tables.
* @param $scope
* @param $timeout
* @param element
* @constructor
*/
function MCTTableController($scope, $timeout, element) {
var self = this;
this.$scope = $scope;
this.element = element;
this.$timeout = $timeout;
this.maxDisplayRows = 50;
this.scrollable = element.find('div');
this.thead = element.find('thead');
this.tbody = element.find('tbody');
this.$scope.sizingRow = {};
this.scrollable.on('scroll', this.onScroll.bind(this));
$scope.visibleRows = [];
/**
* Set default values for optional parameters on a given scope
*/
function setDefaults(scope) {
if (typeof scope.enableFilter === 'undefined') {
scope.enableFilter = true;
scope.filters = {};
}
if (typeof scope.enableSort === 'undefined') {
scope.enableSort = true;
scope.sortColumn = undefined;
scope.sortDirection = undefined;
}
}
setDefaults($scope);
$scope.exportAsCSV = function () {
window.alert("Export!");
};
$scope.toggleSort = function (key) {
if (!$scope.enableSort) {
return;
}
if ($scope.sortColumn !== key) {
$scope.sortColumn = key;
$scope.sortDirection = 'asc';
} else if ($scope.sortDirection === 'asc') {
$scope.sortDirection = 'desc';
} else if ($scope.sortDirection === 'desc') {
$scope.sortColumn = undefined;
$scope.sortDirection = undefined;
}
self.setRows($scope.rows);
};
/*
* Define watches to listen for changes to headers and rows.
*/
$scope.$watchCollection('filters', function () {
self.setRows($scope.rows);
});
$scope.$watch('headers', this.setHeaders.bind(this));
$scope.$watch('rows', this.setRows.bind(this));
/*
* Listen for rows added individually (eg. for real-time tables)
*/
$scope.$on('add:row', this.addRow.bind(this));
$scope.$on('remove:row', this.removeRow.bind(this));
}
/**
* If auto-scroll is enabled, this function will scroll to the
* bottom of the page
* @private
*/
MCTTableController.prototype.scrollToBottom = function () {
var self = this;
//Use timeout to defer execution until next digest when any
// pending UI changes have completed, eg. a new row in the table.
if (this.$scope.autoScroll) {
this.$timeout(function () {
self.scrollable[0].scrollTop = self.scrollable[0].scrollHeight;
});
}
};
/**
* Handles a row add event. Rows can be added as needed using the
* `add:row` broadcast event.
* @private
*/
MCTTableController.prototype.addRow = function (event, rowIndex) {
var row = this.$scope.rows[rowIndex];
//Does the row pass the current filter?
if (this.filterRows([row]).length === 1) {
//Insert the row into the correct position in the array
this.insertSorted(this.$scope.displayRows, row);
//Resize the columns , then update the rows visible in the table
this.resize([this.$scope.sizingRow, row])
.then(this.setVisibleRows.bind(this))
.then(this.scrollToBottom.bind(this));
}
};
/**
* Handles a row remove event. Rows can be removed as needed using the
* `remove:row` broadcast event.
* @private
*/
MCTTableController.prototype.removeRow = function (event, rowIndex) {
var row = this.$scope.rows[rowIndex],
// Do a sequential search here. Only way of finding row is by
// object equality, so array is in effect unsorted.
indexInDisplayRows = this.$scope.displayRows.indexOf(row);
if (indexInDisplayRows !== -1) {
this.$scope.displayRows.splice(indexInDisplayRows, 1);
this.setVisibleRows();
}
};
/**
* @private
*/
MCTTableController.prototype.onScroll = function (event) {
//If user scrolls away from bottom, disable auto-scroll.
// Auto-scroll will be re-enabled if user scrolls to bottom again.
if (this.scrollable[0].scrollTop <
(this.scrollable[0].scrollHeight - this.scrollable[0].offsetHeight)) {
this.$scope.autoScroll = false;
} else {
this.$scope.autoScroll = true;
}
this.setVisibleRows();
this.$scope.$digest();
};
/**
* Sets visible rows based on array
* content and current scroll state.
*/
MCTTableController.prototype.setVisibleRows = function () {
var self = this,
target = this.scrollable[0],
topScroll = target.scrollTop,
bottomScroll = topScroll + target.offsetHeight,
firstVisible,
lastVisible,
totalVisible,
numberOffscreen,
start,
end;
//No need to scroll
if (this.$scope.displayRows.length < this.maxDisplayRows) {
start = 0;
end = this.$scope.displayRows.length;
} else {
//rows has exceeded display maximum, so may be necessary to
// scroll
if (topScroll < this.$scope.headerHeight) {
firstVisible = 0;
} else {
firstVisible = Math.floor(
(topScroll - this.$scope.headerHeight) /
this.$scope.rowHeight
);
}
lastVisible = Math.ceil(
(bottomScroll - this.$scope.headerHeight) /
this.$scope.rowHeight
);
totalVisible = lastVisible - firstVisible;
numberOffscreen = this.maxDisplayRows - totalVisible;
start = firstVisible - Math.floor(numberOffscreen / 2);
end = lastVisible + Math.ceil(numberOffscreen / 2);
if (start < 0) {
start = 0;
end = Math.min(this.maxDisplayRows,
this.$scope.displayRows.length);
} else if (end >= this.$scope.displayRows.length) {
end = this.$scope.displayRows.length;
start = end - this.maxDisplayRows + 1;
}
if (this.$scope.visibleRows[0] &&
this.$scope.visibleRows[0].rowIndex === start &&
this.$scope.visibleRows[this.$scope.visibleRows.length - 1]
.rowIndex === end) {
return; // don't update if no changes are required.
}
}
//Set visible rows from display rows, based on calculated offset.
this.$scope.visibleRows = this.$scope.displayRows.slice(start, end)
.map(function (row, i) {
return {
rowIndex: start + i,
offsetY: ((start + i) * self.$scope.rowHeight) +
self.$scope.headerHeight,
contents: row
};
});
};
/**
* Update table headers with new headers. If filtering is
* enabled, reset filters. If sorting is enabled, reset
* sorting.
*/
MCTTableController.prototype.setHeaders = function (newHeaders) {
if (!newHeaders) {
return;
}
this.$scope.displayHeaders = newHeaders;
if (this.$scope.enableFilter) {
this.$scope.filters = {};
}
// Reset column sort information unless the new headers
// contain the column currently sorted on.
if (this.$scope.enableSort &&
newHeaders.indexOf(this.$scope.sortColumn) === -1) {
this.$scope.sortColumn = undefined;
this.$scope.sortDirection = undefined;
}
this.setRows(this.$scope.rows);
};
/**
* Read styles from the DOM and use them to calculate offsets
* for individual rows.
*/
MCTTableController.prototype.setElementSizes = function () {
var thead = this.thead,
tbody = this.tbody,
firstRow = tbody.find('tr'),
column = firstRow.find('td'),
headerHeight = thead.prop('offsetHeight'),
rowHeight = firstRow.prop('offsetHeight'),
columnWidth,
tableWidth = 0,
overallHeight = headerHeight + (rowHeight *
(this.$scope.displayRows ? this.$scope.displayRows.length - 1 : 0));
this.$scope.columnWidths = [];
while (column.length) {
columnWidth = column.prop('offsetWidth');
this.$scope.columnWidths.push(column.prop('offsetWidth'));
tableWidth += columnWidth;
column = column.next();
}
this.$scope.headerHeight = headerHeight;
this.$scope.rowHeight = rowHeight;
this.$scope.totalHeight = overallHeight;
if (tableWidth > 0) {
this.$scope.totalWidth = tableWidth + 'px';
} else {
this.$scope.totalWidth = 'none';
}
};
/**
* @private
*/
MCTTableController.prototype.insertSorted = function (array, element) {
var index = -1,
self = this,
sortKey = this.$scope.sortColumn;
function binarySearch(searchArray, searchElement, min, max) {
var sampleAt = Math.floor((max - min) / 2) + min;
if (max < min) {
return min; // Element is not in array, min gives direction
}
switch (self.sortComparator(searchElement[sortKey].text,
searchArray[sampleAt][sortKey].text)) {
case -1:
return binarySearch(searchArray, searchElement, min,
sampleAt - 1);
case 0 :
return sampleAt;
case 1 :
return binarySearch(searchArray, searchElement,
sampleAt + 1, max);
}
}
if (!this.$scope.sortColumn || !this.$scope.sortDirection) {
//No sorting applied, push it on the end.
index = array.length;
} else {
//Sort is enabled, perform binary search to find insertion point
index = binarySearch(array, element, 0, array.length - 1);
}
if (index === -1) {
array.unshift(element);
} else if (index === array.length) {
array.push(element);
} else {
array.splice(index, 0, element);
}
};
/**
* Compare two variables, returning a number that represents
* which is larger. Similar to the default array sort
* comparator, but does not coerce all values to string before
* conversion. Strings are lowercased before comparison.
*
* @private
*/
MCTTableController.prototype.sortComparator = function (a, b) {
var result = 0,
sortDirectionMultiplier,
numberA,
numberB;
/**
* Given a value, if it is a number, or a string representation of a
* number, then return a number representation. Otherwise, return
* the original value. It's a little more robust than using just
* Number() or parseFloat, or isNaN in isolation, all of which are
* fairly inconsistent in their results.
* @param value The value to return as a number.
* @returns {*} The value cast to a Number, or the original value if
* a Number representation is not possible.
*/
function toNumber(value) {
var val = !isNaN(Number(value)) && !isNaN(parseFloat(value)) ? Number(value) : value;
return val;
}
numberA = toNumber(a);
numberB = toNumber(b);
//If they're both numbers, then compare them as numbers
if (typeof numberA === "number" && typeof numberB === "number") {
a = numberA;
b = numberB;
}
//If they're both strings, then ignore case
if (typeof a === "string" && typeof b === "string") {
a = a.toLowerCase();
b = b.toLowerCase();
}
if (a < b) {
result = -1;
}
if (a > b) {
result = 1;
}
if (this.$scope.sortDirection === 'asc') {
sortDirectionMultiplier = 1;
} else if (this.$scope.sortDirection === 'desc') {
sortDirectionMultiplier = -1;
}
return result * sortDirectionMultiplier;
};
/**
* Returns a new array which is a result of applying the sort
* criteria defined in $scope.
*
* Does not modify the array that was passed in.
*/
MCTTableController.prototype.sortRows = function (rowsToSort) {
var self = this,
sortKey = this.$scope.sortColumn;
if (!this.$scope.sortColumn || !this.$scope.sortDirection) {
return rowsToSort;
}
return rowsToSort.sort(function (a, b) {
return self.sortComparator(a[sortKey].text, b[sortKey].text);
});
};
/**
* Returns an object which contains the largest values
* for each key in the given set of rows. This is used to
* pre-calculate optimal column sizes without having to render
* every row.
*/
MCTTableController.prototype.buildLargestRow = function (rows) {
var largestRow = rows.reduce(function (prevLargest, row) {
Object.keys(row).forEach(function (key) {
var currentColumn,
currentColumnLength,
largestColumn,
largestColumnLength;
if (row[key]) {
currentColumn = (row[key]).text;
currentColumnLength =
(currentColumn && currentColumn.length) ?
currentColumn.length :
currentColumn;
largestColumn = prevLargest[key] ? prevLargest[key].text : "";
largestColumnLength = largestColumn.length;
if (currentColumnLength > largestColumnLength) {
prevLargest[key] = JSON.parse(JSON.stringify(row[key]));
}
}
});
return prevLargest;
}, JSON.parse(JSON.stringify(rows[0] || {})));
return largestRow;
};
/**
* Calculates the widest row in the table, and if necessary, resizes
* the table accordingly
*
* @param rows the rows on which to resize
* @returns {Promise} a promise that will resolve when resizing has
* occurred.
* @private
*/
MCTTableController.prototype.resize = function (rows) {
this.$scope.sizingRow = this.buildLargestRow(rows);
return this.$timeout(this.setElementSizes.bind(this));
};
/**
* @private
*/
MCTTableController.prototype.filterAndSort = function (rows) {
var displayRows = rows;
if (this.$scope.enableFilter) {
displayRows = this.filterRows(displayRows);
}
if (this.$scope.enableSort) {
displayRows = this.sortRows(displayRows.slice(0));
}
return displayRows;
};
/**
* Update rows with new data. If filtering is enabled, rows
* will be sorted before display.
*/
MCTTableController.prototype.setRows = function (newRows) {
//Nothing to show because no columns visible
if (!this.$scope.displayHeaders || !newRows) {
return;
}
this.$scope.displayRows = this.filterAndSort(newRows || []);
this.resize(newRows).then(this.setVisibleRows.bind(this));
};
/**
* Applies user defined filters to rows. These filters are based on
* the text entered in the search areas in each column.
* @param rowsToFilter {Object[]} The rows to apply filters to
* @returns {Object[]} A filtered copy of the supplied rows
*/
MCTTableController.prototype.filterRows = function (rowsToFilter) {
var filters = {},
self = this;
/**
* Returns true if row matches all filters.
*/
function matchRow(filterMap, row) {
return Object.keys(filterMap).every(function (key) {
if (!row[key]) {
return false;
}
var testVal = String(row[key].text).toLowerCase();
return testVal.indexOf(filterMap[key]) !== -1;
});
}
if (!Object.keys(this.$scope.filters).length) {
return rowsToFilter;
}
Object.keys(this.$scope.filters).forEach(function (key) {
if (!self.$scope.filters[key]) {
return;
}
filters[key] = self.$scope.filters[key].toLowerCase();
});
return rowsToFilter.filter(matchRow.bind(null, filters));
};
return MCTTableController;
}
);