tor-browser

commands.ts (32851B)

---

import {joinPoint, canJoin, findWrapping, liftTarget, canSplit,
       ReplaceStep, ReplaceAroundStep, replaceStep} from "prosemirror-transform"
import {Slice, Fragment, Node, NodeType, Attrs, MarkType, ResolvedPos, ContentMatch} from "prosemirror-model"
import {Selection, EditorState, Transaction, TextSelection, NodeSelection,
       SelectionRange, AllSelection, Command} from "prosemirror-state"
import {EditorView} from "prosemirror-view"

/// Delete the selection, if there is one.
export const deleteSelection: Command = (state, dispatch) => {
 if (state.selection.empty) return false
 if (dispatch) dispatch(state.tr.deleteSelection().scrollIntoView())
 return true
}

function atBlockStart(state: EditorState, view?: EditorView): ResolvedPos | null {
 let {$cursor} = state.selection as TextSelection
 if (!$cursor || (view ? !view.endOfTextblock("backward", state)
                       : $cursor.parentOffset > 0))
   return null
 return $cursor
}

/// If the selection is empty and at the start of a textblock, try to
/// reduce the distance between that block and the one before it—if
/// there's a block directly before it that can be joined, join them.
/// If not, try to move the selected block closer to the next one in
/// the document structure by lifting it out of its parent or moving it
/// into a parent of the previous block. Will use the view for accurate
/// (bidi-aware) start-of-textblock detection if given.
export const joinBackward: Command = (state, dispatch, view) => {
 let $cursor = atBlockStart(state, view)
 if (!$cursor) return false

 let $cut = findCutBefore($cursor)

 // If there is no node before this, try to lift
 if (!$cut) {
   let range = $cursor.blockRange(), target = range && liftTarget(range)
   if (target == null) return false
   if (dispatch) dispatch(state.tr.lift(range!, target).scrollIntoView())
   return true
 }

 let before = $cut.nodeBefore!
 // Apply the joining algorithm
 if (deleteBarrier(state, $cut, dispatch, -1)) return true

 // If the node below has no content and the node above is
 // selectable, delete the node below and select the one above.
 if ($cursor.parent.content.size == 0 &&
     (textblockAt(before, "end") || NodeSelection.isSelectable(before))) {
   for (let depth = $cursor.depth;; depth--) {
     let delStep = replaceStep(state.doc, $cursor.before(depth), $cursor.after(depth), Slice.empty)
     if (delStep && (delStep as ReplaceStep).slice.size < (delStep as ReplaceStep).to - (delStep as ReplaceStep).from) {
       if (dispatch) {
         let tr = state.tr.step(delStep)
         tr.setSelection(textblockAt(before, "end")
           ? Selection.findFrom(tr.doc.resolve(tr.mapping.map($cut.pos, -1)), -1)!
           : NodeSelection.create(tr.doc, $cut.pos - before.nodeSize))
         dispatch(tr.scrollIntoView())
       }
       return true
     }
     if (depth == 1 || $cursor.node(depth - 1).childCount > 1) break
   }
 }

 // If the node before is an atom, delete it
 if (before.isAtom && $cut.depth == $cursor.depth - 1) {
   if (dispatch) dispatch(state.tr.delete($cut.pos - before.nodeSize, $cut.pos).scrollIntoView())
   return true
 }

 return false
}

/// A more limited form of [`joinBackward`](#commands.joinBackward)
/// that only tries to join the current textblock to the one before
/// it, if the cursor is at the start of a textblock.
export const joinTextblockBackward: Command = (state, dispatch, view) => {
 let $cursor = atBlockStart(state, view)
 if (!$cursor) return false
 let $cut = findCutBefore($cursor)
 return $cut ? joinTextblocksAround(state, $cut, dispatch) : false
}

/// A more limited form of [`joinForward`](#commands.joinForward)
/// that only tries to join the current textblock to the one after
/// it, if the cursor is at the end of a textblock.
export const joinTextblockForward: Command = (state, dispatch, view) => {
 let $cursor = atBlockEnd(state, view)
 if (!$cursor) return false
 let $cut = findCutAfter($cursor)
 return $cut ? joinTextblocksAround(state, $cut, dispatch) : false
}

function joinTextblocksAround(state: EditorState, $cut: ResolvedPos, dispatch?: (tr: Transaction) => void) {
 let before = $cut.nodeBefore!, beforeText = before, beforePos = $cut.pos - 1
 for (; !beforeText.isTextblock; beforePos--) {
   if (beforeText.type.spec.isolating) return false
   let child = beforeText.lastChild
   if (!child) return false
   beforeText = child
 }
 let after = $cut.nodeAfter!, afterText = after, afterPos = $cut.pos + 1
 for (; !afterText.isTextblock; afterPos++) {
   if (afterText.type.spec.isolating) return false
   let child = afterText.firstChild
   if (!child) return false
   afterText = child
 }
 let step = replaceStep(state.doc, beforePos, afterPos, Slice.empty) as ReplaceStep | null
 if (!step || step.from != beforePos ||
     step instanceof ReplaceStep && step.slice.size >= afterPos - beforePos) return false
 if (dispatch) {
   let tr = state.tr.step(step)
   tr.setSelection(TextSelection.create(tr.doc, beforePos))
   dispatch(tr.scrollIntoView())
 }
 return true

}

function textblockAt(node: Node, side: "start" | "end", only = false) {
 for (let scan: Node | null = node; scan; scan = (side == "start" ? scan.firstChild : scan.lastChild)) {
   if (scan.isTextblock) return true
   if (only && scan.childCount != 1) return false
 }
 return false
}

/// When the selection is empty and at the start of a textblock, select
/// the node before that textblock, if possible. This is intended to be
/// bound to keys like backspace, after
/// [`joinBackward`](#commands.joinBackward) or other deleting
/// commands, as a fall-back behavior when the schema doesn't allow
/// deletion at the selected point.
export const selectNodeBackward: Command = (state, dispatch, view) => {
 let {$head, empty} = state.selection, $cut: ResolvedPos | null = $head
 if (!empty) return false

 if ($head.parent.isTextblock) {
   if (view ? !view.endOfTextblock("backward", state) : $head.parentOffset > 0) return false
   $cut = findCutBefore($head)
 }
 let node = $cut && $cut.nodeBefore
 if (!node || !NodeSelection.isSelectable(node)) return false
 if (dispatch)
   dispatch(state.tr.setSelection(NodeSelection.create(state.doc, $cut!.pos - node.nodeSize)).scrollIntoView())
 return true
}

function findCutBefore($pos: ResolvedPos): ResolvedPos | null {
 if (!$pos.parent.type.spec.isolating) for (let i = $pos.depth - 1; i >= 0; i--) {
   if ($pos.index(i) > 0) return $pos.doc.resolve($pos.before(i + 1))
   if ($pos.node(i).type.spec.isolating) break
 }
 return null
}

function atBlockEnd(state: EditorState, view?: EditorView): ResolvedPos | null {
 let {$cursor} = state.selection as TextSelection
 if (!$cursor || (view ? !view.endOfTextblock("forward", state)
                       : $cursor.parentOffset < $cursor.parent.content.size))
   return null
 return $cursor
}

/// If the selection is empty and the cursor is at the end of a
/// textblock, try to reduce or remove the boundary between that block
/// and the one after it, either by joining them or by moving the other
/// block closer to this one in the tree structure. Will use the view
/// for accurate start-of-textblock detection if given.
export const joinForward: Command = (state, dispatch, view) => {
 let $cursor = atBlockEnd(state, view)
 if (!$cursor) return false

 let $cut = findCutAfter($cursor)
 // If there is no node after this, there's nothing to do
 if (!$cut) return false

 let after = $cut.nodeAfter!
 // Try the joining algorithm
 if (deleteBarrier(state, $cut, dispatch, 1)) return true

 // If the node above has no content and the node below is
 // selectable, delete the node above and select the one below.
 if ($cursor.parent.content.size == 0 &&
     (textblockAt(after, "start") || NodeSelection.isSelectable(after))) {
   let delStep = replaceStep(state.doc, $cursor.before(), $cursor.after(), Slice.empty)
   if (delStep && (delStep as ReplaceStep).slice.size < (delStep as ReplaceStep).to - (delStep as ReplaceStep).from) {
     if (dispatch) {
       let tr = state.tr.step(delStep)
       tr.setSelection(textblockAt(after, "start") ? Selection.findFrom(tr.doc.resolve(tr.mapping.map($cut.pos)), 1)!
                       : NodeSelection.create(tr.doc, tr.mapping.map($cut.pos)))
       dispatch(tr.scrollIntoView())
     }
     return true
   }
 }

 // If the next node is an atom, delete it
 if (after.isAtom && $cut.depth == $cursor.depth - 1) {
   if (dispatch) dispatch(state.tr.delete($cut.pos, $cut.pos + after.nodeSize).scrollIntoView())
   return true
 }

 return false
}

/// When the selection is empty and at the end of a textblock, select
/// the node coming after that textblock, if possible. This is intended
/// to be bound to keys like delete, after
/// [`joinForward`](#commands.joinForward) and similar deleting
/// commands, to provide a fall-back behavior when the schema doesn't
/// allow deletion at the selected point.
export const selectNodeForward: Command = (state, dispatch, view) => {
 let {$head, empty} = state.selection, $cut: ResolvedPos | null = $head
 if (!empty) return false
 if ($head.parent.isTextblock) {
   if (view ? !view.endOfTextblock("forward", state) : $head.parentOffset < $head.parent.content.size)
     return false
   $cut = findCutAfter($head)
 }
 let node = $cut && $cut.nodeAfter
 if (!node || !NodeSelection.isSelectable(node)) return false
 if (dispatch)
   dispatch(state.tr.setSelection(NodeSelection.create(state.doc, $cut!.pos)).scrollIntoView())
 return true
}

function findCutAfter($pos: ResolvedPos) {
 if (!$pos.parent.type.spec.isolating) for (let i = $pos.depth - 1; i >= 0; i--) {
   let parent = $pos.node(i)
   if ($pos.index(i) + 1 < parent.childCount) return $pos.doc.resolve($pos.after(i + 1))
   if (parent.type.spec.isolating) break
 }
 return null
}

/// Join the selected block or, if there is a text selection, the
/// closest ancestor block of the selection that can be joined, with
/// the sibling above it.
export const joinUp: Command = (state, dispatch) => {
 let sel = state.selection, nodeSel = sel instanceof NodeSelection, point
 if (nodeSel) {
   if ((sel as NodeSelection).node.isTextblock || !canJoin(state.doc, sel.from)) return false
   point = sel.from
 } else {
   point = joinPoint(state.doc, sel.from, -1)
   if (point == null) return false
 }
 if (dispatch) {
   let tr = state.tr.join(point)
   if (nodeSel) tr.setSelection(NodeSelection.create(tr.doc, point - state.doc.resolve(point).nodeBefore!.nodeSize))
   dispatch(tr.scrollIntoView())
 }
 return true
}

/// Join the selected block, or the closest ancestor of the selection
/// that can be joined, with the sibling after it.
export const joinDown: Command = (state, dispatch) => {
 let sel = state.selection, point
 if (sel instanceof NodeSelection) {
   if (sel.node.isTextblock || !canJoin(state.doc, sel.to)) return false
   point = sel.to
 } else {
   point = joinPoint(state.doc, sel.to, 1)
   if (point == null) return false
 }
 if (dispatch)
   dispatch(state.tr.join(point).scrollIntoView())
 return true
}

/// Lift the selected block, or the closest ancestor block of the
/// selection that can be lifted, out of its parent node.
export const lift: Command = (state, dispatch) => {
 let {$from, $to} = state.selection
 let range = $from.blockRange($to), target = range && liftTarget(range)
 if (target == null) return false
 if (dispatch) dispatch(state.tr.lift(range!, target).scrollIntoView())
 return true
}

/// If the selection is in a node whose type has a truthy
/// [`code`](#model.NodeSpec.code) property in its spec, replace the
/// selection with a newline character.
export const newlineInCode: Command = (state, dispatch) => {
 let {$head, $anchor} = state.selection
 if (!$head.parent.type.spec.code || !$head.sameParent($anchor)) return false
 if (dispatch) dispatch(state.tr.insertText("\n").scrollIntoView())
 return true
}

function defaultBlockAt(match: ContentMatch) {
 for (let i = 0; i < match.edgeCount; i++) {
   let {type} = match.edge(i)
   if (type.isTextblock && !type.hasRequiredAttrs()) return type
 }
 return null
}

/// When the selection is in a node with a truthy
/// [`code`](#model.NodeSpec.code) property in its spec, create a
/// default block after the code block, and move the cursor there.
export const exitCode: Command = (state, dispatch) => {
 let {$head, $anchor} = state.selection
 if (!$head.parent.type.spec.code || !$head.sameParent($anchor)) return false
 let above = $head.node(-1), after = $head.indexAfter(-1), type = defaultBlockAt(above.contentMatchAt(after))
 if (!type || !above.canReplaceWith(after, after, type)) return false
 if (dispatch) {
   let pos = $head.after(), tr = state.tr.replaceWith(pos, pos, type.createAndFill()!)
   tr.setSelection(Selection.near(tr.doc.resolve(pos), 1))
   dispatch(tr.scrollIntoView())
 }
 return true
}

/// If a block node is selected, create an empty paragraph before (if
/// it is its parent's first child) or after it.
export const createParagraphNear: Command = (state, dispatch) => {
 let sel = state.selection, {$from, $to} = sel
 if (sel instanceof AllSelection || $from.parent.inlineContent || $to.parent.inlineContent) return false
 let type = defaultBlockAt($to.parent.contentMatchAt($to.indexAfter()))
 if (!type || !type.isTextblock) return false
 if (dispatch) {
   let side = (!$from.parentOffset && $to.index() < $to.parent.childCount ? $from : $to).pos
   let tr = state.tr.insert(side, type.createAndFill()!)
   tr.setSelection(TextSelection.create(tr.doc, side + 1))
   dispatch(tr.scrollIntoView())
 }
 return true
}

/// If the cursor is in an empty textblock that can be lifted, lift the
/// block.
export const liftEmptyBlock: Command = (state, dispatch) => {
 let {$cursor} = state.selection as TextSelection
 if (!$cursor || $cursor.parent.content.size) return false
 if ($cursor.depth > 1 && $cursor.after() != $cursor.end(-1)) {
   let before = $cursor.before()
   if (canSplit(state.doc, before)) {
     if (dispatch) dispatch(state.tr.split(before).scrollIntoView())
     return true
   }
 }
 let range = $cursor.blockRange(), target = range && liftTarget(range)
 if (target == null) return false
 if (dispatch) dispatch(state.tr.lift(range!, target).scrollIntoView())
 return true
}

/// Create a variant of [`splitBlock`](#commands.splitBlock) that uses
/// a custom function to determine the type of the newly split off block.
export function splitBlockAs(
 splitNode?: (node: Node, atEnd: boolean, $from: ResolvedPos) => {type: NodeType, attrs?: Attrs} | null
): Command {
 return (state, dispatch) => {
   let {$from, $to} = state.selection
   if (state.selection instanceof NodeSelection && state.selection.node.isBlock) {
     if (!$from.parentOffset || !canSplit(state.doc, $from.pos)) return false
     if (dispatch) dispatch(state.tr.split($from.pos).scrollIntoView())
     return true
   }

   if (!$from.depth) return false
   let types: (null | {type: NodeType, attrs?: Attrs | null})[] = []
   let splitDepth, deflt, atEnd = false, atStart = false
   for (let d = $from.depth;; d--) {
     let node = $from.node(d)
     if (node.isBlock) {
       atEnd = $from.end(d) == $from.pos + ($from.depth - d)
       atStart = $from.start(d) == $from.pos - ($from.depth - d)
       deflt = defaultBlockAt($from.node(d - 1).contentMatchAt($from.indexAfter(d - 1)))
       let splitType = splitNode && splitNode($to.parent, atEnd, $from)
       types.unshift(splitType || (atEnd && deflt ? {type: deflt} : null))
       splitDepth = d
       break
     } else {
       if (d == 1) return false
       types.unshift(null)
     }
   }

   let tr = state.tr
   if (state.selection instanceof TextSelection || state.selection instanceof AllSelection) tr.deleteSelection()
   let splitPos = tr.mapping.map($from.pos)
   let can = canSplit(tr.doc, splitPos, types.length, types)
   if (!can) {
     types[0] = deflt ? {type: deflt} : null
     can = canSplit(tr.doc, splitPos, types.length, types)
   }
   if (!can) return false
   tr.split(splitPos, types.length, types)
   if (!atEnd && atStart && $from.node(splitDepth).type != deflt) {
     let first = tr.mapping.map($from.before(splitDepth)), $first = tr.doc.resolve(first)
     if (deflt && $from.node(splitDepth - 1).canReplaceWith($first.index(), $first.index() + 1, deflt))
       tr.setNodeMarkup(tr.mapping.map($from.before(splitDepth)), deflt)
   }
   if (dispatch) dispatch(tr.scrollIntoView())
   return true
 }
}

/// Split the parent block of the selection. If the selection is a text
/// selection, also delete its content.
export const splitBlock: Command = splitBlockAs()

/// Acts like [`splitBlock`](#commands.splitBlock), but without
/// resetting the set of active marks at the cursor.
export const splitBlockKeepMarks: Command = (state, dispatch) => {
 return splitBlock(state, dispatch && (tr => {
   let marks = state.storedMarks || (state.selection.$to.parentOffset && state.selection.$from.marks())
   if (marks) tr.ensureMarks(marks)
   dispatch(tr)
 }))
}

/// Move the selection to the node wrapping the current selection, if
/// any. (Will not select the document node.)
export const selectParentNode: Command = (state, dispatch) => {
 let {$from, to} = state.selection, pos
 let same = $from.sharedDepth(to)
 if (same == 0) return false
 pos = $from.before(same)
 if (dispatch) dispatch(state.tr.setSelection(NodeSelection.create(state.doc, pos)))
 return true
}

/// Select the whole document.
export const selectAll: Command = (state, dispatch) => {
 if (dispatch) dispatch(state.tr.setSelection(new AllSelection(state.doc)))
 return true
}

function joinMaybeClear(state: EditorState, $pos: ResolvedPos, dispatch: ((tr: Transaction) => void) | undefined) {
 let before = $pos.nodeBefore, after = $pos.nodeAfter, index = $pos.index()
 if (!before || !after || !before.type.compatibleContent(after.type)) return false
 if (!before.content.size && $pos.parent.canReplace(index - 1, index)) {
   if (dispatch) dispatch(state.tr.delete($pos.pos - before.nodeSize, $pos.pos).scrollIntoView())
   return true
 }
 if (!$pos.parent.canReplace(index, index + 1) || !(after.isTextblock || canJoin(state.doc, $pos.pos)))
   return false
 if (dispatch)
   dispatch(state.tr.join($pos.pos).scrollIntoView())
 return true
}

function deleteBarrier(state: EditorState, $cut: ResolvedPos, dispatch: ((tr: Transaction) => void) | undefined, dir: number) {
 let before = $cut.nodeBefore!, after = $cut.nodeAfter!, conn, match
 let isolated = before.type.spec.isolating || after.type.spec.isolating
 if (!isolated && joinMaybeClear(state, $cut, dispatch)) return true

 let canDelAfter = !isolated && $cut.parent.canReplace($cut.index(), $cut.index() + 1)
 if (canDelAfter &&
     (conn = (match = before.contentMatchAt(before.childCount)).findWrapping(after.type)) &&
     match.matchType(conn[0] || after.type)!.validEnd) {
   if (dispatch) {
     let end = $cut.pos + after.nodeSize, wrap = Fragment.empty
     for (let i = conn.length - 1; i >= 0; i--)
       wrap = Fragment.from(conn[i].create(null, wrap))
     wrap = Fragment.from(before.copy(wrap))
     let tr = state.tr.step(new ReplaceAroundStep($cut.pos - 1, end, $cut.pos, end, new Slice(wrap, 1, 0), conn.length, true))
     let $joinAt = tr.doc.resolve(end + 2 * conn.length)
     if ($joinAt.nodeAfter && $joinAt.nodeAfter.type == before.type &&
         canJoin(tr.doc, $joinAt.pos)) tr.join($joinAt.pos)
     dispatch(tr.scrollIntoView())
   }
   return true
 }

 let selAfter = after.type.spec.isolating || (dir > 0 && isolated) ? null : Selection.findFrom($cut, 1)
 let range = selAfter && selAfter.$from.blockRange(selAfter.$to), target = range && liftTarget(range)
 if (target != null && target >= $cut.depth) {
   if (dispatch) dispatch(state.tr.lift(range!, target).scrollIntoView())
   return true
 }

 if (canDelAfter && textblockAt(after, "start", true) && textblockAt(before, "end")) {
   let at = before, wrap = []
   for (;;) {
     wrap.push(at)
     if (at.isTextblock) break
     at = at.lastChild!
   }
   let afterText = after, afterDepth = 1
   for (; !afterText.isTextblock; afterText = afterText.firstChild!) afterDepth++
   if (at.canReplace(at.childCount, at.childCount, afterText.content)) {
     if (dispatch) {
       let end = Fragment.empty
       for (let i = wrap.length - 1; i >= 0; i--) end = Fragment.from(wrap[i].copy(end))
       let tr = state.tr.step(new ReplaceAroundStep($cut.pos - wrap.length, $cut.pos + after.nodeSize,
                                                    $cut.pos + afterDepth, $cut.pos + after.nodeSize - afterDepth,
                                                    new Slice(end, wrap.length, 0), 0, true))
       dispatch(tr.scrollIntoView())
     }
     return true
   }
 }

 return false
}

function selectTextblockSide(side: number): Command {
 return function(state, dispatch) {
   let sel = state.selection, $pos = side < 0 ? sel.$from : sel.$to
   let depth = $pos.depth
   while ($pos.node(depth).isInline) {
     if (!depth) return false
     depth--
   }
   if (!$pos.node(depth).isTextblock) return false
   if (dispatch)
     dispatch(state.tr.setSelection(TextSelection.create(
       state.doc, side < 0 ? $pos.start(depth) : $pos.end(depth))))
   return true
 }
}

/// Moves the cursor to the start of current text block.
export const selectTextblockStart = selectTextblockSide(-1)

/// Moves the cursor to the end of current text block.
export const selectTextblockEnd = selectTextblockSide(1)

// Parameterized commands

/// Wrap the selection in a node of the given type with the given
/// attributes.
export function wrapIn(nodeType: NodeType, attrs: Attrs | null = null): Command {
 return function(state, dispatch) {
   let {$from, $to} = state.selection
   let range = $from.blockRange($to), wrapping = range && findWrapping(range, nodeType, attrs)
   if (!wrapping) return false
   if (dispatch) dispatch(state.tr.wrap(range!, wrapping).scrollIntoView())
   return true
 }
}

/// Returns a command that tries to set the selected textblocks to the
/// given node type with the given attributes.
export function setBlockType(nodeType: NodeType, attrs: Attrs | null = null): Command {
 return function(state, dispatch) {
   let applicable = false
   for (let i = 0; i < state.selection.ranges.length && !applicable; i++) {
     let {$from: {pos: from}, $to: {pos: to}} = state.selection.ranges[i]
     state.doc.nodesBetween(from, to, (node, pos) => {
       if (applicable) return false
       if (!node.isTextblock || node.hasMarkup(nodeType, attrs)) return
       if (node.type == nodeType) {
         applicable = true
       } else {
         let $pos = state.doc.resolve(pos), index = $pos.index()
         applicable = $pos.parent.canReplaceWith(index, index + 1, nodeType)
       }
     })
   }
   if (!applicable) return false
   if (dispatch) {
     let tr = state.tr
     for (let i = 0; i < state.selection.ranges.length; i++) {
       let {$from: {pos: from}, $to: {pos: to}} = state.selection.ranges[i]
       tr.setBlockType(from, to, nodeType, attrs)
     }
     dispatch(tr.scrollIntoView())
   }
   return true
 }
}

function markApplies(doc: Node, ranges: readonly SelectionRange[], type: MarkType, enterAtoms: boolean) {
 for (let i = 0; i < ranges.length; i++) {
   let {$from, $to} = ranges[i]
   let can = $from.depth == 0 ? doc.inlineContent && doc.type.allowsMarkType(type) : false
   doc.nodesBetween($from.pos, $to.pos, (node, pos) => {
     if (can || !enterAtoms && node.isAtom && node.isInline && pos >= $from.pos && pos + node.nodeSize <= $to.pos)
       return false
     can = node.inlineContent && node.type.allowsMarkType(type)
   })
   if (can) return true
 }
 return false
}

function removeInlineAtoms(ranges: readonly SelectionRange[]): readonly SelectionRange[] {
 let result = []
 for (let i = 0; i < ranges.length; i++) {
   let {$from, $to} = ranges[i]
   $from.doc.nodesBetween($from.pos, $to.pos, (node, pos) => {
     if (node.isAtom && node.content.size && node.isInline && pos >= $from.pos && pos + node.nodeSize <= $to.pos) {
       if (pos + 1 > $from.pos) result.push(new SelectionRange($from, $from.doc.resolve(pos + 1)))
       $from = $from.doc.resolve(pos + 1 + node.content.size)
       return false
     }
   })
   if ($from.pos < $to.pos) result.push(new SelectionRange($from, $to))
 }
 return result
}

/// Create a command function that toggles the given mark with the
/// given attributes. Will return `false` when the current selection
/// doesn't support that mark. This will remove the mark if any marks
/// of that type exist in the selection, or add it otherwise. If the
/// selection is empty, this applies to the [stored
/// marks](#state.EditorState.storedMarks) instead of a range of the
/// document.
export function toggleMark(markType: MarkType, attrs: Attrs | null = null, options?: {
 /// Controls whether, when part of the selected range has the mark
 /// already and part doesn't, the mark is removed (`true`, the
 /// default) or added (`false`).
 removeWhenPresent?: boolean
 /// When set to false, this will prevent the command from acting on
 /// the content of inline nodes marked as
 /// [atoms](#model.NodeSpec.atom) that are completely covered by a
 /// selection range.
 enterInlineAtoms?: boolean
 /// By default, this command doesn't apply to leading and trailing
 /// whitespace in the selection. Set this to `true` to change that.
 includeWhitespace?: boolean
}): Command {
 let removeWhenPresent = (options && options.removeWhenPresent) !== false
 let enterAtoms = (options && options.enterInlineAtoms) !== false
 let dropSpace = !(options && options.includeWhitespace)
 return function(state, dispatch) {
   let {empty, $cursor, ranges} = state.selection as TextSelection
   if ((empty && !$cursor) || !markApplies(state.doc, ranges, markType, enterAtoms)) return false
   if (dispatch) {
     if ($cursor) {
       if (markType.isInSet(state.storedMarks || $cursor.marks()))
         dispatch(state.tr.removeStoredMark(markType))
       else
         dispatch(state.tr.addStoredMark(markType.create(attrs)))
     } else {
       let add, tr = state.tr
       if (!enterAtoms) ranges = removeInlineAtoms(ranges)
       if (removeWhenPresent) {
         add = !ranges.some(r => state.doc.rangeHasMark(r.$from.pos, r.$to.pos, markType))
       } else {
         add = !ranges.every(r => {
           let missing = false
           tr.doc.nodesBetween(r.$from.pos, r.$to.pos, (node, pos, parent) => {
             if (missing) return false
             missing = !markType.isInSet(node.marks) && !!parent && parent.type.allowsMarkType(markType) &&
               !(node.isText && /^\s*$/.test(node.textBetween(Math.max(0, r.$from.pos - pos),
                                                              Math.min(node.nodeSize, r.$to.pos - pos))))
           })
           return !missing
         })
       }
       for (let i = 0; i < ranges.length; i++) {
         let {$from, $to} = ranges[i]
         if (!add) {
           tr.removeMark($from.pos, $to.pos, markType)
         } else {
           let from = $from.pos, to = $to.pos, start = $from.nodeAfter, end = $to.nodeBefore
           let spaceStart = dropSpace && start && start.isText ? /^\s*/.exec(start.text!)![0].length : 0
           let spaceEnd = dropSpace && end && end.isText ? /\s*$/.exec(end.text!)![0].length : 0
           if (from + spaceStart < to) { from += spaceStart; to -= spaceEnd }
           tr.addMark(from, to, markType.create(attrs))
         }
       }
       dispatch(tr.scrollIntoView())
     }
   }
   return true
 }
}

function wrapDispatchForJoin(dispatch: (tr: Transaction) => void, isJoinable: (a: Node, b: Node) => boolean) {
 return (tr: Transaction) => {
   if (!tr.isGeneric) return dispatch(tr)

   let ranges: number[] = []
   for (let i = 0; i < tr.mapping.maps.length; i++) {
     let map = tr.mapping.maps[i]
     for (let j = 0; j < ranges.length; j++)
       ranges[j] = map.map(ranges[j])
     map.forEach((_s, _e, from, to) => ranges.push(from, to))
   }

   // Figure out which joinable points exist inside those ranges,
   // by checking all node boundaries in their parent nodes.
   let joinable = []
   for (let i = 0; i < ranges.length; i += 2) {
     let from = ranges[i], to = ranges[i + 1]
     let $from = tr.doc.resolve(from), depth = $from.sharedDepth(to), parent = $from.node(depth)
     for (let index = $from.indexAfter(depth), pos = $from.after(depth + 1); pos <= to; ++index) {
       let after = parent.maybeChild(index)
       if (!after) break
       if (index && joinable.indexOf(pos) == -1) {
         let before = parent.child(index - 1)
         if (before.type == after.type && isJoinable(before, after))
           joinable.push(pos)
       }
       pos += after.nodeSize
     }
   }
   // Join the joinable points
   joinable.sort((a, b) => a - b)
   for (let i = joinable.length - 1; i >= 0; i--) {
     if (canJoin(tr.doc, joinable[i])) tr.join(joinable[i])
   }
   dispatch(tr)
 }
}

/// Wrap a command so that, when it produces a transform that causes
/// two joinable nodes to end up next to each other, those are joined.
/// Nodes are considered joinable when they are of the same type and
/// when the `isJoinable` predicate returns true for them or, if an
/// array of strings was passed, if their node type name is in that
/// array.
export function autoJoin(
 command: Command,
 isJoinable: ((before: Node, after: Node) => boolean) | readonly string[]
): Command {
 let canJoin = Array.isArray(isJoinable) ? (node: Node) => isJoinable.indexOf(node.type.name) > -1
   : isJoinable as (a: Node, b: Node) => boolean
 return (state, dispatch, view) => command(state, dispatch && wrapDispatchForJoin(dispatch, canJoin), view)
}

/// Combine a number of command functions into a single function (which
/// calls them one by one until one returns true).
export function chainCommands(...commands: readonly Command[]): Command {
 return function(state, dispatch, view) {
   for (let i = 0; i < commands.length; i++)
     if (commands[i](state, dispatch, view)) return true
   return false
 }
}

let backspace = chainCommands(deleteSelection, joinBackward, selectNodeBackward)
let del = chainCommands(deleteSelection, joinForward, selectNodeForward)

/// A basic keymap containing bindings not specific to any schema.
/// Binds the following keys (when multiple commands are listed, they
/// are chained with [`chainCommands`](#commands.chainCommands)):
///
/// * **Enter** to `newlineInCode`, `createParagraphNear`, `liftEmptyBlock`, `splitBlock`
/// * **Mod-Enter** to `exitCode`
/// * **Backspace** and **Mod-Backspace** to `deleteSelection`, `joinBackward`, `selectNodeBackward`
/// * **Delete** and **Mod-Delete** to `deleteSelection`, `joinForward`, `selectNodeForward`
/// * **Mod-Delete** to `deleteSelection`, `joinForward`, `selectNodeForward`
/// * **Mod-a** to `selectAll`
export const pcBaseKeymap: {[key: string]: Command} = {
 "Enter": chainCommands(newlineInCode, createParagraphNear, liftEmptyBlock, splitBlock),
 "Mod-Enter": exitCode,
 "Backspace": backspace,
 "Mod-Backspace": backspace,
 "Shift-Backspace": backspace,
 "Delete": del,
 "Mod-Delete": del,
 "Mod-a": selectAll
}

/// A copy of `pcBaseKeymap` that also binds **Ctrl-h** like Backspace,
/// **Ctrl-d** like Delete, **Alt-Backspace** like Ctrl-Backspace, and
/// **Ctrl-Alt-Backspace**, **Alt-Delete**, and **Alt-d** like
/// Ctrl-Delete.
export const macBaseKeymap: {[key: string]: Command} = {
 "Ctrl-h": pcBaseKeymap["Backspace"],
 "Alt-Backspace": pcBaseKeymap["Mod-Backspace"],
 "Ctrl-d": pcBaseKeymap["Delete"],
 "Ctrl-Alt-Backspace": pcBaseKeymap["Mod-Delete"],
 "Alt-Delete": pcBaseKeymap["Mod-Delete"],
 "Alt-d": pcBaseKeymap["Mod-Delete"],
 "Ctrl-a": selectTextblockStart,
 "Ctrl-e": selectTextblockEnd
}
for (let key in pcBaseKeymap) (macBaseKeymap as any)[key] = pcBaseKeymap[key]

const mac = typeof navigator != "undefined" ? /Mac|iP(hone|[oa]d)/.test(navigator.platform)
         // @ts-ignore
         : typeof os != "undefined" && os.platform ? os.platform() == "darwin" : false

/// Depending on the detected platform, this will hold
/// [`pcBasekeymap`](#commands.pcBaseKeymap) or
/// [`macBaseKeymap`](#commands.macBaseKeymap).
export const baseKeymap: {[key: string]: Command} = mac ? macBaseKeymap : pcBaseKeymap