# names.ludic - a name nobody else in the place is using: not another person, not one the place
# keeps for itself (NpcWorld.taken: a vendor), and not somebody who left a little while ago

export function npc_name_used(npc_st: NpcState, n: string) -> bool {
  if NpcWorld.taken(n) { return true }
  let all = npc_walkers(npc_st)
  for i in 0 .. len(all) { if all[i].active and all[i].name == n { return true } }
  let posts = npc_posts(npc_st)
  for i in 0 .. len(posts) { if posts[i].active and posts[i].name == n { return true } }
  for i in 0 .. len(npc_st.np_recent) { if npc_st.np_recent[i] != "" and npc_st.np_recent[i] == n { return true } }
  return false
}

# a free name from the body's pool, from a place in it the dice choose ("" when the pool is empty)
export function npc_pick_name(npc_st: NpcState, body: int) -> string {
  var n = 0
  for i in 0 .. NPCN_COUNT { if NpcNames[i].body == body { n += 1 } }
  if n == 0 { return "" }
  let start = npc_between(npc_st, 0, n - 1)
  for k in 0 .. n {
    let name = np_name_nth(body, (start + k) % n)
    if not npc_name_used(npc_st, name) { return name }
  }
  return np_name_nth(body, start)
}
# the body's j-th name in the table, counted in place rather than gathered into a list
function np_name_nth(body: int, j: int) -> string {
  var seen = 0
  for i in 0 .. NPCN_COUNT {
    if NpcNames[i].body == body {
      if seen == j { return NpcNames[i].name }
      seen += 1
    }
  }
  return ""
}

# the last eight who left, in a ring of slots made with the state
function np_left(npc_st: mut NpcState, name: string) -> void {
  npc_st.np_recent[npc_st.np_rnext] = name
  npc_st.np_rnext = (npc_st.np_rnext + 1) % len(npc_st.np_recent)
}
function np_recent_new() -> []string {
  let l = new []string
  for i in 0 .. 8 { push(l, "") }
  return l
}
function np_recent_clear(npc_st: mut NpcState) -> void {
  for i in 0 .. len(npc_st.np_recent) { npc_st.np_recent[i] = "" }
  npc_st.np_rnext = 0
}

# how many pairs share a name, the place's own names included
export function npc_name_clashes(npc_st: NpcState) -> int {
  var dup = 0
  let all = npc_walkers(npc_st)
  for i in 0 .. len(all) {
    let p = all[i]
    if not p.active { continue }
    if NpcWorld.taken(p.name) { dup += 1 }
    for k in i + 1 .. len(all) { if all[k].active and all[k].name == p.name { dup += 1 } }
  }
  return dup
}