- return false unless @cursor?
- if @is_lone_space @cursor.n # false if it's not in a tag
- if @cursor.i is 1
- # don't delete the space, because then it would collapse
- # instead leave a space after the cursor
- new_cursor = new_cursor_position n: @cursor.n, i: 0
- if new_cursor?
- @move_cursor new_cursor
- else
- @kill_cursor()
- else
- # cursor at the begining of an element that contains only a space
- parent = @cursor.n.parent
- new_cursor = find_prev_cursor_position @tree, @cursor
- if new_cursor?
- if new_cursor.n is @cursor.n or new_cursor.n is parent
- new_cursor = null
- tag = @cursor.n.parent
- if tag is @tree_parent
- console.log "top-level text not supported" # FIXME
- return false
- for n, i in tag.parent.children
- if n is tag
- tag.parent.el.removeChild tag.el
- tag.parent.children.splice i, 1
- break
- @changed()
- if new_cursor?
- # re-check, in case it moved or is invalid now
- new_cursor = new_cursor_position n: new_cursor.n, i: new_cursor.i
+ return unless @cursor?
+ new_cursor = null
+ run = null
+ changed = true
+ if @cursor.i is 0 # cursor is at start of text node
+ run ?= @get_text_run @cursor.n
+ run_i = run.indexOf(@cursor.n)
+ if run_i is 0 # if at start of text run
+ block = @find_block_parent @cursor.n
+ prev_cursor = find_prev_cursor_position @tree, n: @cursor.n, i: 0
+ if prev_cursor is null # if in first text run of document
+ # do nothing (there's nothing text-like to the left of the cursor)
+ return
+ # else merge with prev/outer text run
+ pcb = @find_block_parent prev_cursor.n
+ while block.children.length > 0
+ @move_node block.children[0], pcb
+ @remove_node block
+ # merge possible consecutive text nodes at @cursor
+ merge_state = n: @cursor.n
+ @_merge_left merge_state
+ @text_cleanup merge_state.n
+ new_cursor = new_cursor_position n: merge_state.n, i: merge_state.i
+ else # at start of text node, but not start of text run
+ prev = run[run_i - 1]
+ if prev.type is 'text' # if previous in text run is text
+ if prev.text.length is 1 # if emptying prev (in text run)
+ @_backspace_node_helper prev, run, run_i
+ merge_state = n: @cursor.n, i: @cursor.i
+ @_merge_left merge_state
+ @text_cleanup merge_state.n
+ new_cursor = new_cursor_position n: merge_state.n, i: merge_state.i
+ else # prev in run is text with muliple chars
+ # delete last character in prev
+ prev.text = prev.text.substr(0, prev.text.length - 1)
+ prev.el.textContent = prev.text
+ @text_cleanup @cursor.n
+ new_cursor = new_cursor_position n: @cursor.n, i: @cursor.i
+ else if prev.name is 'br' or prev.name is 'hr'
+ @_backspace_node_helper prev, run, run_i
+ merge_state = n: @cursor.n, i: @cursor.i
+ @_merge_left merge_state
+ @text_cleanup merge_state.n
+ new_cursor = new_cursor_position n: merge_state.n, i: merge_state.i
+ # FIXME implement this:
+ # else # if prev (in run) is inline-block
+ # if that inline-block has text in it
+ # delete last char in prev inlineblock
+ # if that empties it
+ # delete it
+ # merge left
+ # else
+ # move cursor inside
+ # else
+ # delete prev (inline) block
+ # merge left
+ # auto-delete this @cursor.parent(s) if this empties them
+ else # cursor is not at start of text node
+ run ?= @get_text_run @cursor.n
+ if @cursor.n.text.length is 1 # if emptying text node
+ if run.length is 1 # if emptying text run (of text/br/hr/inline-block)
+ # remove inline-parents of @cursor.n
+ block = @find_block_parent @cursor.n
+ changed = false
+ n = @cursor.n.parent
+ # note: this doesn't use _backspace_node_helper because:
+ # 1. we don't want to delete the target node (we're replacing it's contents)
+ # 2. we want to track whether anything was removed
+ # 3. we know already know there's no other text from this run anywhere
+ while n and n isnt block
+ changed = true
+ while n.children.length > 0
+ @move_node n.children[0], n.parent, n
+ @remove_node n
+ n = n.parent
+ # replace @cursor.n with a single (preserved) space
+ if @cursor.n.text != ' '
+ changed = true
+ @cursor.n.text = @cursor.n.el.textContent = ' '
+ if changed
+ @text_cleanup @cursor.n
+ # place the cursor to the left of that space
+ new_cursor = new_cursor_position n: @cursor.n, i: 0
+ else # emptying a text node (but not a whole text run)
+ # figure out where cursor should land
+ block = @find_block_parent @cursor.n
+ new_cursor = find_prev_cursor_position @tree, n: @cursor.n, i: 0
+ ncb = @find_block_parent new_cursor.n
+ if ncb isnt block
+ new_cursor = find_next_cursor_position @tree, n: @cursor.n, i: 1
+ # delete text node and cleanup emptied parents
+ run_i = run.indexOf @cursor.n
+ @_backspace_node_helper @cursor.n, run, run_i
+ # see if new adjacent siblings should merge
+ # TODO make smarter
+ if run_i > 0 and run_i + 1 < run.length
+ if run[run_i - 1].type is 'text' and run[run_i + 1].type is 'text'
+ merge_state = n: run[run_i + 1]
+ @_merge_left merge_state
+ if merge_state.moved_cursor
+ new_cursor = merge_state
+ # update whitespace preservation
+ @text_cleanup(block)
+ # update cursor x/y in case things moved around