feat: add desktop/web app package (#2606)

Co-authored-by: adamdotdevin <[email protected]>
Co-authored-by: Adam <[email protected]>
Co-authored-by: GitHub Action <[email protected]>

4 files changed, 103 insertions, 0 deletions

diff --git a/packages/app/src/utils/binary.ts b/packages/app/src/utils/binary.ts
new file mode 100644
index 000000000..3d8f61851
--- /dev/null
+++ b/packages/app/src/utils/binary.ts
@@ -0,0 +1,41 @@
+export namespace Binary {
+  export function search<T>(array: T[], id: string, compare: (item: T) => string): { found: boolean; index: number } {
+    let left = 0
+    let right = array.length - 1
+
+    while (left <= right) {
+      const mid = Math.floor((left + right) / 2)
+      const midId = compare(array[mid])
+
+      if (midId === id) {
+        return { found: true, index: mid }
+      } else if (midId < id) {
+        left = mid + 1
+      } else {
+        right = mid - 1
+      }
+    }
+
+    return { found: false, index: left }
+  }
+
+  export function insert<T>(array: T[], item: T, compare: (item: T) => string): T[] {
+    const id = compare(item)
+    let left = 0
+    let right = array.length
+
+    while (left < right) {
+      const mid = Math.floor((left + right) / 2)
+      const midId = compare(array[mid])
+
+      if (midId < id) {
+        left = mid + 1
+      } else {
+        right = mid
+      }
+    }
+
+    array.splice(left, 0, item)
+    return array
+  }
+}
diff --git a/packages/app/src/utils/dom.ts b/packages/app/src/utils/dom.ts
new file mode 100644
index 000000000..4f3724c7c
--- /dev/null
+++ b/packages/app/src/utils/dom.ts
@@ -0,0 +1,51 @@
+export function getCharacterOffsetInLine(lineElement: Element, targetNode: Node, offset: number): number {
+  const r = document.createRange()
+  r.selectNodeContents(lineElement)
+  r.setEnd(targetNode, offset)
+  return r.toString().length
+}
+
+export function getNodeOffsetInLine(lineElement: Element, charIndex: number): { node: Node; offset: number } | null {
+  const walker = document.createTreeWalker(lineElement, NodeFilter.SHOW_TEXT, null)
+  let remaining = Math.max(0, charIndex)
+  let lastText: Node | null = null
+  let lastLen = 0
+  let node: Node | null
+  while ((node = walker.nextNode())) {
+    const len = node.textContent?.length || 0
+    lastText = node
+    lastLen = len
+    if (remaining <= len) return { node, offset: remaining }
+    remaining -= len
+  }
+  if (lastText) return { node: lastText, offset: lastLen }
+  if (lineElement.firstChild) return { node: lineElement.firstChild, offset: 0 }
+  return null
+}
+
+export function getSelectionInContainer(
+  container: HTMLElement,
+): { sl: number; sch: number; el: number; ech: number } | null {
+  const s = window.getSelection()
+  if (!s || s.rangeCount === 0) return null
+  const r = s.getRangeAt(0)
+  const sc = r.startContainer
+  const ec = r.endContainer
+  const getLineElement = (n: Node) =>
+    (n.nodeType === Node.TEXT_NODE ? (n.parentElement as Element) : (n as Element))?.closest(".line")
+  const sle = getLineElement(sc)
+  const ele = getLineElement(ec)
+  if (!sle || !ele) return null
+  if (!container.contains(sle as Node) || !container.contains(ele as Node)) return null
+  const cc = container.querySelector("code") as HTMLElement | null
+  if (!cc) return null
+  const lines = Array.from(cc.querySelectorAll(".line"))
+  const sli = lines.indexOf(sle as Element)
+  const eli = lines.indexOf(ele as Element)
+  if (sli === -1 || eli === -1) return null
+  const sl = sli + 1
+  const el = eli + 1
+  const sch = getCharacterOffsetInLine(sle as Element, sc, r.startOffset)
+  const ech = getCharacterOffsetInLine(ele as Element, ec, r.endOffset)
+  return { sl, sch, el, ech }
+}
diff --git a/packages/app/src/utils/index.ts b/packages/app/src/utils/index.ts
new file mode 100644
index 000000000..ae89e4417
--- /dev/null
+++ b/packages/app/src/utils/index.ts
@@ -0,0 +1,2 @@
+export * from "./path"
+export * from "./dom"
diff --git a/packages/app/src/utils/path.ts b/packages/app/src/utils/path.ts
new file mode 100644
index 000000000..d6a066e80
--- /dev/null
+++ b/packages/app/src/utils/path.ts
@@ -0,0 +1,9 @@
+export function getFilename(path: string) {
+  const parts = path.split("/")
+  return parts[parts.length - 1]
+}
+
+export function getFileExtension(path: string) {
+  const parts = path.split(".")
+  return parts[parts.length - 1]
+}