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| -rw-r--r-- | comm/mail/base/content/widgets/tree-selection.mjs | 744 |
1 files changed, 744 insertions, 0 deletions
diff --git a/comm/mail/base/content/widgets/tree-selection.mjs b/comm/mail/base/content/widgets/tree-selection.mjs new file mode 100644 index 0000000000..022af7316e --- /dev/null +++ b/comm/mail/base/content/widgets/tree-selection.mjs @@ -0,0 +1,744 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/** + * This implementation attempts to mimic the behavior of nsTreeSelection. In + * a few cases, this leads to potentially confusing actions. I attempt to note + * when we are doing this and why we do it. + * + * Unit test is in mail/base/test/unit/test_treeSelection.js + */ +export class TreeSelection { + QueryInterface = ChromeUtils.generateQI(["nsITreeSelection"]); + + /** + * The current XULTreeElement, appropriately QueryInterfaced. May be null. + */ + _tree; + + /** + * Where the focus rectangle (that little dotted thing) shows up. Just + * because something is focused does not mean it is actually selected. + */ + _currentIndex; + /** + * The view index where the shift is anchored when it is not (conceptually) + * the same as _currentIndex. This only happens when you perform a ranged + * selection. In that case, the start index of the ranged selection becomes + * the shift pivot (and the _currentIndex becomes the end of the ranged + * selection.) + * It gets cleared whenever the selection changes and it's not the result of + * a call to rangedSelect. + */ + _shiftSelectPivot; + /** + * A list of [lowIndexInclusive, highIndexInclusive] non-overlapping, + * non-adjacent 'tuples' sort in ascending order. + */ + _ranges; + /** + * The number of currently selected rows. + */ + _count; + + // In the case of the stand-alone message window, there's no tree, but + // there's a view. + _view; + + /** + * A set of indices we think is invalid. + */ + _invalidIndices; + + constructor(tree) { + this._tree = tree; + + this._currentIndex = null; + this._shiftSelectPivot = null; + this._ranges = []; + this._count = 0; + this._invalidIndices = new Set(); + + this._selectEventsSuppressed = false; + } + + /** + * Mark the currently selected rows as invalid. + */ + _invalidateSelection() { + for (let [low, high] of this._ranges) { + for (let i = low; i <= high; i++) { + this._invalidIndices.add(i); + } + } + } + + /** + * Call `invalidateRow` on the tree for each row we think is invalid. + */ + _doInvalidateRows() { + if (this.selectEventsSuppressed) { + return; + } + if (this._tree) { + for (let i of this._invalidIndices) { + this._tree.invalidateRow(i); + } + } + this._invalidIndices.clear(); + } + + /** + * Call `invalidateRange` on the tree. + * + * @param {number} startIndex - The first index to invalidate. + * @param {number?} endIndex - The last index to invalidate. If not given, + * defaults to the index of the last row. + */ + _doInvalidateRange(startIndex, endIndex) { + let noEndIndex = endIndex === undefined; + if (noEndIndex) { + if (!this._view || this.view.rowCount == 0) { + this._doInvalidateAll(); + return; + } + endIndex = this._view.rowCount - 1; + } + if (this._tree) { + this._tree.invalidateRange(startIndex, endIndex); + } + for (let i of this._invalidIndices) { + if (i >= startIndex && (noEndIndex || i <= endIndex)) { + this._invalidIndices.delete(i); + } + } + } + + /** + * Call `invalidate` on the tree. + */ + _doInvalidateAll() { + if (this._tree) { + this._tree.invalidate(); + } + this._invalidIndices.clear(); + } + + get tree() { + return this._tree; + } + set tree(tree) { + this._tree = tree; + } + + get view() { + return this._view; + } + set view(view) { + this._view = view; + } + /** + * Although the nsITreeSelection documentation doesn't say, what this method + * is supposed to do is check if the seltype attribute on the XUL tree is any + * of the following: "single" (only a single row may be selected at a time, + * "cell" (a single cell may be selected), or "text" (the row gets selected + * but only the primary column shows up as selected.) + * + * @returns false because we don't support single-selection. + */ + get single() { + return false; + } + + _updateCount() { + this._count = 0; + for (let [low, high] of this._ranges) { + this._count += high - low + 1; + } + } + + get count() { + return this._count; + } + + isSelected(viewIndex) { + for (let [low, high] of this._ranges) { + if (viewIndex >= low && viewIndex <= high) { + return true; + } + } + return false; + } + + /** + * Select the given row. It does nothing if that row was already selected. + */ + select(viewIndex) { + this._invalidateSelection(); + // current index will provide our effective shift pivot + this._shiftSelectPivot = null; + this._currentIndex = viewIndex != -1 ? viewIndex : null; + + if (this._count == 1 && this._ranges[0][0] == viewIndex) { + return; + } + + if (viewIndex >= 0) { + this._count = 1; + this._ranges = [[viewIndex, viewIndex]]; + this._invalidIndices.add(viewIndex); + } else { + this._count = 0; + this._ranges = []; + } + + this._doInvalidateRows(); + this._fireSelectionChanged(); + } + + timedSelect(index, delay) { + throw new Error("We do not implement timed selection."); + } + + toggleSelect(index) { + this._currentIndex = index; + // If nothing's selected, select index + if (this._count == 0) { + this._count = 1; + this._ranges = [[index, index]]; + } else { + let added = false; + for (let [iTupe, [low, high]] of this._ranges.entries()) { + // below the range? add it to the existing range or create a new one + if (index < low) { + this._count++; + // is it just below an existing range? (range fusion only happens in the + // high case, not here.) + if (index == low - 1) { + this._ranges[iTupe][0] = index; + added = true; + break; + } + // then it gets its own range + this._ranges.splice(iTupe, 0, [index, index]); + added = true; + break; + } + // in the range? will need to either nuke, shrink, or split the range to + // remove it + if (index >= low && index <= high) { + this._count--; + if (index == low && index == high) { + // nuke + this._ranges.splice(iTupe, 1); + } else if (index == low) { + // lower shrink + this._ranges[iTupe][0] = index + 1; + } else if (index == high) { + // upper shrink + this._ranges[iTupe][1] = index - 1; + } else { + // split + this._ranges.splice(iTupe, 1, [low, index - 1], [index + 1, high]); + } + added = true; + break; + } + // just above the range? fuse into the range, and possibly the next + // range up. + if (index == high + 1) { + this._count++; + // see if there is another range and there was just a gap of one between + // the two ranges. + if ( + iTupe + 1 < this._ranges.length && + this._ranges[iTupe + 1][0] == index + 1 + ) { + // yes, merge the ranges + this._ranges.splice(iTupe, 2, [low, this._ranges[iTupe + 1][1]]); + added = true; + break; + } + // nope, no merge required, just update the range + this._ranges[iTupe][1] = index; + added = true; + break; + } + // otherwise we need to keep going + } + + if (!added) { + this._count++; + this._ranges.push([index, index]); + } + } + + this._invalidIndices.add(index); + this._doInvalidateRows(); + this._fireSelectionChanged(); + } + + /** + * @param rangeStart If omitted, it implies a shift-selection is happening, + * in which case we use _shiftSelectPivot as the start if we have it, + * _currentIndex if we don't, and if we somehow didn't have a + * _currentIndex, we use the range end. + * @param rangeEnd Just the inclusive end of the range. + * @param augment Does this set a new selection or should it be merged with + * the existing selection? + */ + rangedSelect(rangeStart, rangeEnd, augment) { + if (rangeStart == -1) { + if (this._shiftSelectPivot != null) { + rangeStart = this._shiftSelectPivot; + } else if (this._currentIndex != null) { + rangeStart = this._currentIndex; + } else { + rangeStart = rangeEnd; + } + } + + this._shiftSelectPivot = rangeStart; + this._currentIndex = rangeEnd; + + // enforce our ordering constraint for our ranges + if (rangeStart > rangeEnd) { + [rangeStart, rangeEnd] = [rangeEnd, rangeStart]; + } + + // if we're not augmenting, then this is really easy. + if (!augment) { + this._invalidateSelection(); + + this._count = rangeEnd - rangeStart + 1; + this._ranges = [[rangeStart, rangeEnd]]; + + for (let i = rangeStart; i <= rangeEnd; i++) { + this._invalidIndices.add(i); + } + + this._doInvalidateRows(); + this._fireSelectionChanged(); + return; + } + + // Iterate over our existing set of ranges, finding the 'range' of ranges + // that our new range overlaps or simply obviates. + // Overlap variables track blocks we need to keep some part of, Nuke + // variables are for blocks that get spliced out. For our purposes, all + // overlap blocks are also nuke blocks. + let lowOverlap, lowNuke, highNuke, highOverlap; + // in case there is no overlap, also figure an insertionPoint + let insertionPoint = this._ranges.length; // default to the end + for (let [iTupe, [low, high]] of this._ranges.entries()) { + // If it's completely include the range, it should be nuked + if (rangeStart <= low && rangeEnd >= high) { + if (lowNuke == null) { + // only the first one we see is the low one + lowNuke = iTupe; + } + highNuke = iTupe; + } + // If our new range start is inside a range or is adjacent, it's overlap + if ( + rangeStart >= low - 1 && + rangeStart <= high + 1 && + lowOverlap == null + ) { + lowOverlap = lowNuke = highNuke = iTupe; + } + // If our new range ends inside a range or is adjacent, it's overlap + if (rangeEnd >= low - 1 && rangeEnd <= high + 1) { + highOverlap = highNuke = iTupe; + if (lowNuke == null) { + lowNuke = iTupe; + } + } + + // we're done when no more overlap is possible + if (rangeEnd < low) { + insertionPoint = iTupe; + break; + } + } + + if (lowOverlap != null) { + rangeStart = Math.min(rangeStart, this._ranges[lowOverlap][0]); + } + if (highOverlap != null) { + rangeEnd = Math.max(rangeEnd, this._ranges[highOverlap][1]); + } + if (lowNuke != null) { + this._ranges.splice(lowNuke, highNuke - lowNuke + 1, [ + rangeStart, + rangeEnd, + ]); + } else { + this._ranges.splice(insertionPoint, 0, [rangeStart, rangeEnd]); + } + for (let i = rangeStart; i <= rangeEnd; i++) { + this._invalidIndices.add(i); + } + + this._updateCount(); + this._doInvalidateRows(); + this._fireSelectionChanged(); + } + + /** + * This is basically RangedSelect but without insertion of a new range and we + * don't need to worry about adjacency. + * Oddly, nsTreeSelection doesn't fire a selection changed event here... + */ + clearRange(rangeStart, rangeEnd) { + // Iterate over our existing set of ranges, finding the 'range' of ranges + // that our clear range overlaps or simply obviates. + // Overlap variables track blocks we need to keep some part of, Nuke + // variables are for blocks that get spliced out. For our purposes, all + // overlap blocks are also nuke blocks. + let lowOverlap, lowNuke, highNuke, highOverlap; + for (let [iTupe, [low, high]] of this._ranges.entries()) { + // If we completely include the range, it should be nuked + if (rangeStart <= low && rangeEnd >= high) { + if (lowNuke == null) { + // only the first one we see is the low one + lowNuke = iTupe; + } + highNuke = iTupe; + } + // If our new range start is inside a range, it's nuke and maybe overlap + if (rangeStart >= low && rangeStart <= high && lowNuke == null) { + lowNuke = highNuke = iTupe; + // it's only overlap if we don't match at the low end + if (rangeStart > low) { + lowOverlap = iTupe; + } + } + // If our new range ends inside a range, it's nuke and maybe overlap + if (rangeEnd >= low && rangeEnd <= high) { + highNuke = iTupe; + // it's only overlap if we don't match at the high end + if (rangeEnd < high) { + highOverlap = iTupe; + } + if (lowNuke == null) { + lowNuke = iTupe; + } + } + + // we're done when no more overlap is possible + if (rangeEnd < low) { + break; + } + } + // nothing to do since there's nothing to nuke + if (lowNuke == null) { + return; + } + let args = [lowNuke, highNuke - lowNuke + 1]; + if (lowOverlap != null) { + args.push([this._ranges[lowOverlap][0], rangeStart - 1]); + } + if (highOverlap != null) { + args.push([rangeEnd + 1, this._ranges[highOverlap][1]]); + } + this._ranges.splice.apply(this._ranges, args); + + for (let i = rangeStart; i <= rangeEnd; i++) { + this._invalidIndices.add(i); + } + + this._updateCount(); + this._doInvalidateRows(); + // note! nsTreeSelection doesn't fire a selection changed event, so neither + // do we, but it seems like we should + } + + /** + * nsTreeSelection always fires a select notification when the range is + * cleared, even if there is no effective chance in selection. + */ + clearSelection() { + this._invalidateSelection(); + this._shiftSelectPivot = null; + this._count = 0; + this._ranges = []; + + this._doInvalidateRows(); + this._fireSelectionChanged(); + } + + /** + * Select all with no rows is a no-op, otherwise we select all and notify. + */ + selectAll() { + if (!this._view) { + return; + } + + let view = this._view; + let rowCount = view.rowCount; + + // no-ops-ville + if (!rowCount) { + return; + } + + this._count = rowCount; + this._ranges = [[0, rowCount - 1]]; + + this._doInvalidateAll(); + this._fireSelectionChanged(); + } + + getRangeCount() { + return this._ranges.length; + } + getRangeAt(rangeIndex, minObj, maxObj) { + if (rangeIndex < 0 || rangeIndex >= this._ranges.length) { + throw new Error("Try a real range index next time."); + } + [minObj.value, maxObj.value] = this._ranges[rangeIndex]; + } + + /** + * Helper method to adjust points in the face of row additions/removal. + * + * @param point The point, null if there isn't one, or an index otherwise. + * @param deltaAt The row at which the change is happening. + * @param delta The number of rows added if positive, or the (negative) + * number of rows removed. + */ + _adjustPoint(point, deltaAt, delta) { + // if there is no point, no change + if (point == null) { + return point; + } + // if the point is before the change, no change + if (point < deltaAt) { + return point; + } + // if it's a deletion and it includes the point, clear it + if (delta < 0 && point >= deltaAt && point + delta < deltaAt) { + return null; + } + // (else) the point is at/after the change, compensate + return point + delta; + } + /** + * Find the index of the range, if any, that contains the given index, and + * the index at which to insert a range if one does not exist. + * + * @returns A tuple containing: 1) the index if there is one, null otherwise, + * 2) the index at which to insert a range that would contain the point. + */ + _findRangeContainingRow(index) { + for (let [iTupe, [low, high]] of this._ranges.entries()) { + if (index >= low && index <= high) { + return [iTupe, iTupe]; + } + if (index < low) { + return [null, iTupe]; + } + } + return [null, this._ranges.length]; + } + + /** + * When present, a list of calls made to adjustSelection. See + * |logAdjustSelectionForReplay| and |replayAdjustSelectionLog|. + */ + _adjustSelectionLog = null; + /** + * Start logging calls to adjustSelection made against this instance. You + * would do this because you are replacing an existing selection object + * with this instance for the purposes of creating a transient selection. + * Of course, you want the original selection object to be up-to-date when + * you go to put it back, so then you can call replayAdjustSelectionLog + * with that selection object and everything will be peachy. + */ + logAdjustSelectionForReplay() { + this._adjustSelectionLog = []; + } + /** + * Stop logging calls to adjustSelection and replay the existing log against + * selection. + * + * @param selection {nsITreeSelection}. + */ + replayAdjustSelectionLog(selection) { + if (this._adjustSelectionLog.length) { + // Temporarily disable selection events because adjustSelection is going + // to generate an event each time otherwise, and better 1 event than + // many. + selection.selectEventsSuppressed = true; + for (let [index, count] of this._adjustSelectionLog) { + selection.adjustSelection(index, count); + } + selection.selectEventsSuppressed = false; + } + this._adjustSelectionLog = null; + } + + adjustSelection(index, count) { + // nothing to do if there is no actual change + if (!count) { + return; + } + + if (this._adjustSelectionLog) { + this._adjustSelectionLog.push([index, count]); + } + + // adjust our points + this._shiftSelectPivot = this._adjustPoint( + this._shiftSelectPivot, + index, + count + ); + this._currentIndex = this._adjustPoint(this._currentIndex, index, count); + + // If we are adding rows, we want to split any range at index and then + // translate all of the ranges above that point up. + if (count > 0) { + let [iContain, iInsert] = this._findRangeContainingRow(index); + if (iContain != null) { + let [low, high] = this._ranges[iContain]; + // if it is the low value, we just want to shift the range entirely, so + // do nothing (and keep iInsert pointing at it for translation) + // if it is not the low value, then there must be at least two values so + // we should split it and only translate the new/upper block + if (index != low) { + this._ranges.splice(iContain, 1, [low, index - 1], [index, high]); + iInsert++; + } + } + // now translate everything from iInsert on up + for (let iTrans = iInsert; iTrans < this._ranges.length; iTrans++) { + let [low, high] = this._ranges[iTrans]; + this._ranges[iTrans] = [low + count, high + count]; + } + // invalidate and fire selection change notice + this._doInvalidateRange(index); + this._fireSelectionChanged(); + return; + } + + // If we are removing rows, we are basically clearing the range that is + // getting deleted and translating everyone above the remaining point + // downwards. The one trick is we may have to merge the lowest translated + // block. + let saveSuppress = this.selectEventsSuppressed; + this.selectEventsSuppressed = true; + this.clearRange(index, index - count - 1); + // translate + let iTrans = this._findRangeContainingRow(index)[1]; + for (; iTrans < this._ranges.length; iTrans++) { + let [low, high] = this._ranges[iTrans]; + // for the first range, low may be below the index, in which case it + // should not get translated + this._ranges[iTrans] = [low >= index ? low + count : low, high + count]; + } + // we may have to merge the lowest translated block because it may now be + // adjacent to the previous block + if ( + iTrans > 0 && + iTrans < this._ranges.length && + this._ranges[iTrans - 1][1] == this._ranges[iTrans][0] + ) { + this._ranges[iTrans - 1][1] = this._ranges[iTrans][1]; + this._ranges.splice(iTrans, 1); + } + + this._doInvalidateRange(index); + this.selectEventsSuppressed = saveSuppress; + } + + get selectEventsSuppressed() { + return this._selectEventsSuppressed; + } + /** + * Control whether selection events are suppressed. For consistency with + * nsTreeSelection, we always generate a selection event when a value of + * false is assigned, even if the value was already false. + */ + set selectEventsSuppressed(suppress) { + if (this._selectEventsSuppressed == suppress) { + return; + } + + this._selectEventsSuppressed = suppress; + if (!suppress) { + this._fireSelectionChanged(); + } + } + + /** + * Note that we bypass any XUL "onselect" handler that may exist and go + * straight to the view. If you have a tree, you shouldn't be using us, + * so this seems aboot right. + */ + _fireSelectionChanged() { + // don't fire if we are suppressed; we will fire when un-suppressed + if (this.selectEventsSuppressed) { + return; + } + let view = this._tree?.view ?? this._view; + + // We might not have a view if we're in the middle of setting up things + view?.selectionChanged(); + } + + get currentIndex() { + if (this._currentIndex == null) { + return -1; + } + return this._currentIndex; + } + /** + * Sets the current index. Other than updating the variable, this just + * invalidates the tree row if we have a tree. + * The real selection object would send a DOM event we don't care about. + */ + set currentIndex(index) { + if (index == this.currentIndex) { + return; + } + + this._invalidateSelection(); + this._currentIndex = index != -1 ? index : null; + this._invalidIndices.add(index); + this._doInvalidateRows(); + } + + get shiftSelectPivot() { + return this._shiftSelectPivot != null ? this._shiftSelectPivot : -1; + } + + /* + * Functions after this aren't part of the nsITreeSelection interface. + */ + + /** + * Duplicate this selection on another nsITreeSelection. This is useful + * when you would like to discard this selection for a real tree selection. + * We assume that both selections are for the same tree. + * + * @note We don't transfer the correct shiftSelectPivot over. + * @note This will fire a selectionChanged event on the tree view. + * + * @param selection an nsITreeSelection to duplicate this selection onto + */ + duplicateSelection(selection) { + selection.selectEventsSuppressed = true; + selection.clearSelection(); + for (let [iTupe, [low, high]] of this._ranges.entries()) { + selection.rangedSelect(low, high, iTupe > 0); + } + + selection.currentIndex = this.currentIndex; + // This will fire a selectionChanged event + selection.selectEventsSuppressed = false; + } +} |