--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.cms/lib/codemirror/src/model/selection_updates.js	Fri Oct 11 22:40:23 2024 +0000
@@ -0,0 +1,216 @@
+import { signalLater } from "../util/operation_group.js"
+import { ensureCursorVisible } from "../display/scrolling.js"
+import { clipPos, cmp, Pos } from "../line/pos.js"
+import { getLine } from "../line/utils_line.js"
+import { hasHandler, signal, signalCursorActivity } from "../util/event.js"
+import { lst, sel_dontScroll } from "../util/misc.js"
+
+import { addSelectionToHistory } from "./history.js"
+import { normalizeSelection, Range, Selection, simpleSelection } from "./selection.js"
+
+// The 'scroll' parameter given to many of these indicated whether
+// the new cursor position should be scrolled into view after
+// modifying the selection.
+
+// If shift is held or the extend flag is set, extends a range to
+// include a given position (and optionally a second position).
+// Otherwise, simply returns the range between the given positions.
+// Used for cursor motion and such.
+export function extendRange(range, head, other, extend) {
+  if (extend) {
+    let anchor = range.anchor
+    if (other) {
+      let posBefore = cmp(head, anchor) < 0
+      if (posBefore != (cmp(other, anchor) < 0)) {
+        anchor = head
+        head = other
+      } else if (posBefore != (cmp(head, other) < 0)) {
+        head = other
+      }
+    }
+    return new Range(anchor, head)
+  } else {
+    return new Range(other || head, head)
+  }
+}
+
+// Extend the primary selection range, discard the rest.
+export function extendSelection(doc, head, other, options, extend) {
+  if (extend == null) extend = doc.cm && (doc.cm.display.shift || doc.extend)
+  setSelection(doc, new Selection([extendRange(doc.sel.primary(), head, other, extend)], 0), options)
+}
+
+// Extend all selections (pos is an array of selections with length
+// equal the number of selections)
+export function extendSelections(doc, heads, options) {
+  let out = []
+  let extend = doc.cm && (doc.cm.display.shift || doc.extend)
+  for (let i = 0; i < doc.sel.ranges.length; i++)
+    out[i] = extendRange(doc.sel.ranges[i], heads[i], null, extend)
+  let newSel = normalizeSelection(doc.cm, out, doc.sel.primIndex)
+  setSelection(doc, newSel, options)
+}
+
+// Updates a single range in the selection.
+export function replaceOneSelection(doc, i, range, options) {
+  let ranges = doc.sel.ranges.slice(0)
+  ranges[i] = range
+  setSelection(doc, normalizeSelection(doc.cm, ranges, doc.sel.primIndex), options)
+}
+
+// Reset the selection to a single range.
+export function setSimpleSelection(doc, anchor, head, options) {
+  setSelection(doc, simpleSelection(anchor, head), options)
+}
+
+// Give beforeSelectionChange handlers a change to influence a
+// selection update.
+function filterSelectionChange(doc, sel, options) {
+  let obj = {
+    ranges: sel.ranges,
+    update: function(ranges) {
+      this.ranges = []
+      for (let i = 0; i < ranges.length; i++)
+        this.ranges[i] = new Range(clipPos(doc, ranges[i].anchor),
+                                   clipPos(doc, ranges[i].head))
+    },
+    origin: options && options.origin
+  }
+  signal(doc, "beforeSelectionChange", doc, obj)
+  if (doc.cm) signal(doc.cm, "beforeSelectionChange", doc.cm, obj)
+  if (obj.ranges != sel.ranges) return normalizeSelection(doc.cm, obj.ranges, obj.ranges.length - 1)
+  else return sel
+}
+
+export function setSelectionReplaceHistory(doc, sel, options) {
+  let done = doc.history.done, last = lst(done)
+  if (last && last.ranges) {
+    done[done.length - 1] = sel
+    setSelectionNoUndo(doc, sel, options)
+  } else {
+    setSelection(doc, sel, options)
+  }
+}
+
+// Set a new selection.
+export function setSelection(doc, sel, options) {
+  setSelectionNoUndo(doc, sel, options)
+  addSelectionToHistory(doc, doc.sel, doc.cm ? doc.cm.curOp.id : NaN, options)
+}
+
+export function setSelectionNoUndo(doc, sel, options) {
+  if (hasHandler(doc, "beforeSelectionChange") || doc.cm && hasHandler(doc.cm, "beforeSelectionChange"))
+    sel = filterSelectionChange(doc, sel, options)
+
+  let bias = options && options.bias ||
+    (cmp(sel.primary().head, doc.sel.primary().head) < 0 ? -1 : 1)
+  setSelectionInner(doc, skipAtomicInSelection(doc, sel, bias, true))
+
+  if (!(options && options.scroll === false) && doc.cm && doc.cm.getOption("readOnly") != "nocursor")
+    ensureCursorVisible(doc.cm)
+}
+
+function setSelectionInner(doc, sel) {
+  if (sel.equals(doc.sel)) return
+
+  doc.sel = sel
+
+  if (doc.cm) {
+    doc.cm.curOp.updateInput = 1
+    doc.cm.curOp.selectionChanged = true
+    signalCursorActivity(doc.cm)
+  }
+  signalLater(doc, "cursorActivity", doc)
+}
+
+// Verify that the selection does not partially select any atomic
+// marked ranges.
+export function reCheckSelection(doc) {
+  setSelectionInner(doc, skipAtomicInSelection(doc, doc.sel, null, false))
+}
+
+// Return a selection that does not partially select any atomic
+// ranges.
+function skipAtomicInSelection(doc, sel, bias, mayClear) {
+  let out
+  for (let i = 0; i < sel.ranges.length; i++) {
+    let range = sel.ranges[i]
+    let old = sel.ranges.length == doc.sel.ranges.length && doc.sel.ranges[i]
+    let newAnchor = skipAtomic(doc, range.anchor, old && old.anchor, bias, mayClear)
+    let newHead = range.head == range.anchor ? newAnchor : skipAtomic(doc, range.head, old && old.head, bias, mayClear)
+    if (out || newAnchor != range.anchor || newHead != range.head) {
+      if (!out) out = sel.ranges.slice(0, i)
+      out[i] = new Range(newAnchor, newHead)
+    }
+  }
+  return out ? normalizeSelection(doc.cm, out, sel.primIndex) : sel
+}
+
+function skipAtomicInner(doc, pos, oldPos, dir, mayClear) {
+  let line = getLine(doc, pos.line)
+  if (line.markedSpans) for (let i = 0; i < line.markedSpans.length; ++i) {
+    let sp = line.markedSpans[i], m = sp.marker
+
+    // Determine if we should prevent the cursor being placed to the left/right of an atomic marker
+    // Historically this was determined using the inclusiveLeft/Right option, but the new way to control it
+    // is with selectLeft/Right
+    let preventCursorLeft = ("selectLeft" in m) ? !m.selectLeft : m.inclusiveLeft
+    let preventCursorRight = ("selectRight" in m) ? !m.selectRight : m.inclusiveRight
+
+    if ((sp.from == null || (preventCursorLeft ? sp.from <= pos.ch : sp.from < pos.ch)) &&
+        (sp.to == null || (preventCursorRight ? sp.to >= pos.ch : sp.to > pos.ch))) {
+      if (mayClear) {
+        signal(m, "beforeCursorEnter")
+        if (m.explicitlyCleared) {
+          if (!line.markedSpans) break
+          else {--i; continue}
+        }
+      }
+      if (!m.atomic) continue
+
+      if (oldPos) {
+        let near = m.find(dir < 0 ? 1 : -1), diff
+        if (dir < 0 ? preventCursorRight : preventCursorLeft)
+          near = movePos(doc, near, -dir, near && near.line == pos.line ? line : null)
+        if (near && near.line == pos.line && (diff = cmp(near, oldPos)) && (dir < 0 ? diff < 0 : diff > 0))
+          return skipAtomicInner(doc, near, pos, dir, mayClear)
+      }
+
+      let far = m.find(dir < 0 ? -1 : 1)
+      if (dir < 0 ? preventCursorLeft : preventCursorRight)
+        far = movePos(doc, far, dir, far.line == pos.line ? line : null)
+      return far ? skipAtomicInner(doc, far, pos, dir, mayClear) : null
+    }
+  }
+  return pos
+}
+
+// Ensure a given position is not inside an atomic range.
+export function skipAtomic(doc, pos, oldPos, bias, mayClear) {
+  let dir = bias || 1
+  let found = skipAtomicInner(doc, pos, oldPos, dir, mayClear) ||
+      (!mayClear && skipAtomicInner(doc, pos, oldPos, dir, true)) ||
+      skipAtomicInner(doc, pos, oldPos, -dir, mayClear) ||
+      (!mayClear && skipAtomicInner(doc, pos, oldPos, -dir, true))
+  if (!found) {
+    doc.cantEdit = true
+    return Pos(doc.first, 0)
+  }
+  return found
+}
+
+function movePos(doc, pos, dir, line) {
+  if (dir < 0 && pos.ch == 0) {
+    if (pos.line > doc.first) return clipPos(doc, Pos(pos.line - 1))
+    else return null
+  } else if (dir > 0 && pos.ch == (line || getLine(doc, pos.line)).text.length) {
+    if (pos.line < doc.first + doc.size - 1) return Pos(pos.line + 1, 0)
+    else return null
+  } else {
+    return new Pos(pos.line, pos.ch + dir)
+  }
+}
+
+export function selectAll(cm) {
+  cm.setSelection(Pos(cm.firstLine(), 0), Pos(cm.lastLine()), sel_dontScroll)
+}