# wire_read.ludic - reading a request in place: numbers, words and quoted strings from dl_in, nothing made
function dl_skip(st: mut DevlinkState) -> void { while st.dl_at < st.dl_n and (st.dl_in[st.dl_at] == 32 or st.dl_in[st.dl_at] == 10 or st.dl_in[st.dl_at] == 13) { st.dl_at += 1 } }

function dl_done(st: mut DevlinkState) -> bool {
  dl_skip(st)
  return st.dl_at >= st.dl_n
}

# the word at the cursor is `w` (and ends there): then past it
function dl_word(st: mut DevlinkState, w: string) -> bool {
  dl_skip(st)
  let n = len(w)
  if st.dl_at + n > st.dl_n { return false }
  for i in 0 .. n { if st.dl_in[st.dl_at + i] != w[i] { return false } }
  if st.dl_at + n < st.dl_n and st.dl_in[st.dl_at + n] != 32 and st.dl_in[st.dl_at + n] != 10 and st.dl_in[st.dl_at + n] != 13 { return false }
  st.dl_at += n
  return true
}

function dl_int(st: mut DevlinkState) -> int {
  dl_skip(st)
  var neg = false
  if st.dl_at < st.dl_n and st.dl_in[st.dl_at] == 45 {
    neg = true
    st.dl_at += 1
  }
  var v = 0
  var digits = 0
  while st.dl_at < st.dl_n and st.dl_in[st.dl_at] >= 48 and st.dl_in[st.dl_at] <= 57 and digits < 10 {
    v = v * 10 + (st.dl_in[st.dl_at] - 48)
    st.dl_at += 1
    digits += 1
  }
  if digits == 0 or (st.dl_at < st.dl_n and st.dl_in[st.dl_at] > 32) { st.dl_bad = true }
  if neg { return -v }
  return v
}

function dl_float(st: mut DevlinkState) -> float {
  dl_skip(st)
  var neg = false
  if st.dl_at < st.dl_n and st.dl_in[st.dl_at] == 45 {
    neg = true
    st.dl_at += 1
  }
  var v = 0.0
  var digits = 0
  while st.dl_at < st.dl_n and st.dl_in[st.dl_at] >= 48 and st.dl_in[st.dl_at] <= 57 {
    v = v * 10.0 + float(st.dl_in[st.dl_at] - 48)
    st.dl_at += 1
    digits += 1
  }
  if st.dl_at < st.dl_n and st.dl_in[st.dl_at] == 46 {
    st.dl_at += 1
    var f = 0.1
    while st.dl_at < st.dl_n and st.dl_in[st.dl_at] >= 48 and st.dl_in[st.dl_at] <= 57 {
      v = v + f * float(st.dl_in[st.dl_at] - 48)
      f = f * 0.1
      st.dl_at += 1
      digits += 1
    }
  }
  if digits == 0 or (st.dl_at < st.dl_n and st.dl_in[st.dl_at] > 32) { st.dl_bad = true }
  if neg { return -v }
  return v
}

# a quoted string into dl_str, unescaped: its length, or -1 (dl_bad) when it is not one
function dl_quoted(st: mut DevlinkState) -> int {
  dl_skip(st)
  if st.dl_at >= st.dl_n or st.dl_in[st.dl_at] != 34 {
    st.dl_bad = true
    return -1
  }
  st.dl_at += 1
  var n = 0
  while st.dl_at < st.dl_n and st.dl_in[st.dl_at] != 34 {
    var c = st.dl_in[st.dl_at]
    if c == 92 and st.dl_at + 1 < st.dl_n {
      st.dl_at += 1
      c = st.dl_in[st.dl_at]
    }
    st.dl_str[n] = c
    n += 1
    st.dl_at += 1
  }
  if st.dl_at >= st.dl_n {
    st.dl_bad = true
    return -1
  }
  st.dl_at += 1
  return n
}