From 667fb91567dc7a763a42e62dadadea76ee130356 Mon Sep 17 00:00:00 2001 From: James Allen Date: Fri, 17 Mar 2017 15:44:37 +0000 Subject: [PATCH] Update RangesTracker to include undo logic --- .../app/coffee/RangesTracker.coffee | 78 ++++++++++++------- 1 file changed, 49 insertions(+), 29 deletions(-) diff --git a/services/document-updater/app/coffee/RangesTracker.coffee b/services/document-updater/app/coffee/RangesTracker.coffee index 865ecf4ef6..a9c43e9816 100644 --- a/services/document-updater/app/coffee/RangesTracker.coffee +++ b/services/document-updater/app/coffee/RangesTracker.coffee @@ -1,5 +1,5 @@ -load = (EventEmitter) -> - class RangesTracker extends EventEmitter +load = () -> + class RangesTracker # The purpose of this class is to track a set of inserts and deletes to a document, like # track changes in Word. We store these as a set of ShareJs style ranges: # {i: "foo", p: 42} # Insert 'foo' at offset 42 @@ -36,6 +36,7 @@ load = (EventEmitter) -> # middle of a previous insert by the first user, the original insert will be split into two. constructor: (@changes = [], @comments = []) -> @setIdSeed(RangesTracker.generateIdSeed()) + @resetDirtyState() getIdSeed: () -> return @id_seed @@ -75,7 +76,7 @@ load = (EventEmitter) -> comment = @getComment(comment_id) return if !comment? @comments = @comments.filter (c) -> c.id != comment_id - @emit "comment:removed", comment + @_markAsDirty comment, "comment", "removed" getChange: (change_id) -> change = null @@ -103,7 +104,11 @@ load = (EventEmitter) -> @addComment(op, metadata) else throw new Error("unknown op type") - + + applyOps: (ops, metadata = {}) -> + for op in ops + @applyOp(op, metadata) + addComment: (op, metadata) -> # TODO: Don't allow overlapping comments? @comments.push comment = { @@ -114,18 +119,18 @@ load = (EventEmitter) -> t: op.t metadata } - @emit "comment:added", comment + @_markAsDirty comment, "comment", "added" return comment applyInsertToComments: (op) -> for comment in @comments if op.p <= comment.op.p comment.op.p += op.i.length - @emit "comment:moved", comment + @_markAsDirty comment, "comment", "moved" else if op.p < comment.op.p + comment.op.c.length offset = op.p - comment.op.p comment.op.c = comment.op.c[0..(offset-1)] + op.i + comment.op.c[offset...] - @emit "comment:moved", comment + @_markAsDirty comment, "comment", "moved" applyDeleteToComments: (op) -> op_start = op.p @@ -138,7 +143,7 @@ load = (EventEmitter) -> if op_end <= comment_start # delete is fully before comment comment.op.p -= op_length - @emit "comment:moved", comment + @_markAsDirty comment, "comment", "moved" else if op_start >= comment_end # delete is fully after comment, nothing to do else @@ -161,12 +166,13 @@ load = (EventEmitter) -> comment.op.p = Math.min(comment_start, op_start) comment.op.c = remaining_before + remaining_after - @emit "comment:moved", comment + @_markAsDirty comment, "comment", "moved" applyInsertToChanges: (op, metadata) -> op_start = op.p op_length = op.i.length op_end = op.p + op_length + undoing = !!op.u already_merged = false @@ -184,8 +190,9 @@ load = (EventEmitter) -> change.op.p += op_length moved_changes.push change else if op_start == change_start - # If the insert matches the start of the delete, just remove it from the delete instead - if change.op.d.length >= op.i.length and change.op.d.slice(0, op.i.length) == op.i + # If we are undoing, then we want to cancel any existing delete ranges if we can. + # Check if the insert matches the start of the delete, and just remove it from the delete instead if so. + if undoing and change.op.d.length >= op.i.length and change.op.d.slice(0, op.i.length) == op.i change.op.d = change.op.d.slice(op.i.length) change.op.p += op.i.length if change.op.d == "" @@ -203,15 +210,15 @@ load = (EventEmitter) -> # Only merge inserts if they are from the same user is_same_user = metadata.user_id == change.metadata.user_id - # If this is an insert op at the end of an existing insert with a delete following, and it cancels out the following - # delete then we shouldn't append it to this insert, but instead only cancel the following delete. + # If we are undoing, then our changes will be removed from any delete ops just after. In that case, if there is also + # an insert op just before, then we shouldn't append it to this insert, but instead only cancel the following delete. # E.g. # foo|<--- about to insert 'b' here # inserted 'foo' --^ ^-- deleted 'bar' # should become just 'foo' not 'foob' (with the delete marker becoming just 'ar'), . next_change = @changes[i+1] is_op_adjacent_to_next_delete = next_change? and next_change.op.d? and op.p == change_end and next_change.op.p == op.p - will_op_cancel_next_delete = is_op_adjacent_to_next_delete and next_change.op.d.slice(0, op.i.length) == op.i + will_op_cancel_next_delete = undoing and is_op_adjacent_to_next_delete and next_change.op.d.slice(0, op.i.length) == op.i # If there is a delete at the start of the insert, and we're inserting # at the start, we SHOULDN'T merge since the delete acts as a partition. @@ -281,8 +288,8 @@ load = (EventEmitter) -> for change in remove_changes @_removeChange change - if moved_changes.length > 0 - @emit "changes:moved", moved_changes + for change in moved_changes + @_markAsDirty change, "change", "moved" applyDeleteToChanges: (op, metadata) -> op_start = op.p @@ -406,8 +413,8 @@ load = (EventEmitter) -> @_removeChange change moved_changes = moved_changes.filter (c) -> c != change - if moved_changes.length > 0 - @emit "changes:moved", moved_changes + for change in moved_changes + @_markAsDirty change, "change", "moved" _addOp: (op, metadata) -> change = { @@ -427,17 +434,11 @@ load = (EventEmitter) -> else return -1 - if op.d? - @emit "delete:added", change - else if op.i? - @emit "insert:added", change + @_markAsDirty(change, "change", "added") _removeChange: (change) -> @changes = @changes.filter (c) -> c.id != change.id - if change.op.d? - @emit "delete:removed", change - else if change.op.i? - @emit "insert:removed", change + @_markAsDirty change, "change", "removed" _applyOpModifications: (content, op_modifications) -> # Put in descending position order, with deleting first if at the same offset @@ -486,13 +487,32 @@ load = (EventEmitter) -> previous_change = change return { moved_changes, remove_changes } + resetDirtyState: () -> + @_dirtyState = { + comment: { + moved: {} + removed: {} + added: {} + } + change: { + moved: {} + removed: {} + added: {} + } + } + + getDirtyState: () -> + return @_dirtyState + + _markAsDirty: (object, type, action) -> + @_dirtyState[type][action][object.id] = object + _clone: (object) -> clone = {} (clone[k] = v for k,v of object) return clone if define? - define ["utils/EventEmitter"], load + define [], load else - EventEmitter = require("events").EventEmitter - module.exports = load(EventEmitter) \ No newline at end of file + module.exports = load()