opencode/packages/app/src/context/file/path.ts

export function stripFileProtocol(input: string) {
  if (!input.startsWith("file://")) return input
  return input.slice("file://".length)
}

export function stripQueryAndHash(input: string) {
  const hashIndex = input.indexOf("#")
  const queryIndex = input.indexOf("?")

  if (hashIndex !== -1 && queryIndex !== -1) {
    return input.slice(0, Math.min(hashIndex, queryIndex))
  }

  if (hashIndex !== -1) return input.slice(0, hashIndex)
  if (queryIndex !== -1) return input.slice(0, queryIndex)
  return input
}

export function unquoteGitPath(input: string) {
  if (!input.startsWith('"')) return input
  if (!input.endsWith('"')) return input
  const body = input.slice(1, -1)
  const bytes: number[] = []

  for (let i = 0; i < body.length; i++) {
    const char = body[i]!
    if (char !== "\\") {
      bytes.push(char.charCodeAt(0))
      continue
    }

    const next = body[i + 1]
    if (!next) {
      bytes.push("\\".charCodeAt(0))
      continue
    }

    if (next >= "0" && next <= "7") {
      const chunk = body.slice(i + 1, i + 4)
      const match = chunk.match(/^[0-7]{1,3}/)
      if (!match) {
        bytes.push(next.charCodeAt(0))
        i++
        continue
      }
      bytes.push(parseInt(match[0], 8))
      i += match[0].length
      continue
    }

    const escaped =
      next === "n"
        ? "\n"
        : next === "r"
          ? "\r"
          : next === "t"
            ? "\t"
            : next === "b"
              ? "\b"
              : next === "f"
                ? "\f"
                : next === "v"
                  ? "\v"
                  : next === "\\" || next === '"'
                    ? next
                    : undefined

    bytes.push((escaped ?? next).charCodeAt(0))
    i++
  }

  return new TextDecoder().decode(new Uint8Array(bytes))
}

export function createPathHelpers(scope: () => string) {
  const normalize = (input: string) => {
    const root = scope()
    const prefix = root.endsWith("/") ? root : root + "/"

    let path = unquoteGitPath(stripQueryAndHash(stripFileProtocol(input)))

    if (path.startsWith(prefix)) {
      path = path.slice(prefix.length)
    }

    if (path.startsWith(root)) {
      path = path.slice(root.length)
    }

    if (path.startsWith("./")) {
      path = path.slice(2)
    }

    if (path.startsWith("/")) {
      path = path.slice(1)
    }

    return path
  }

  const tab = (input: string) => {
    const path = normalize(input)
    return `file://${path}`
  }

  const pathFromTab = (tabValue: string) => {
    if (!tabValue.startsWith("file://")) return
    return normalize(tabValue)
  }

  const normalizeDir = (input: string) => normalize(input).replace(/\/+$/, "")

  return {
    normalize,
    tab,
    pathFromTab,
    normalizeDir,
  }
}