# quests.ludic — RPG Module D: quests + objectives, driven by events (#59).
#
# A quest is data: a state plus a list of objectives (kind + needed count). Progress
# is reported through Quest.notify — a game routes its existing gameplay signals
# (a kill, a pickup, a tile entered, a dialog choice) into it, and matching active
# objectives tick up; when all of a quest's objectives are met it auto-completes.
# A global flag store (Dict) records world state for branching. All state is in
# module Dicts/arrays, so world_save captures the journal for free.
#
# objective kind convention: 0 kill, 1 collect, 2 reach, 3 talk, 4 flag (extend
# with your own kind ints + a Quest.notify from the matching listener).
# quest state: 0 hidden, 1 available, 2 active, 3 done, 4 failed.

const QUEST_MAX: int = 128
const OBJ_MAX: int = 512



event QuestStarted { quest: int = 0 }
event QuestCompleted { quest: int = 0 }
event ObjectiveProgressed { quest: int = 0, objective: int = 0, have: int = 0, need: int = 0 }

# Quest.define(name) — register a quest (state hidden). Returns id.
@Namespace(Quest) function quest_define(rpg_st: mut RpgState, name: pointer) -> int {
  if rpg_st.quest_n >= QUEST_MAX { return -1 }
  let id = rpg_st.quest_n
  rpg_st.quest_state[id] = 0
  rpg_st.quest_n += 1
  Dict.set(rpg_st.quest_reg, name, id)
  return id
}
@Namespace(Quest) function quest_id(rpg_st: mut RpgState, name: pointer) -> int { return Dict.get_or(rpg_st.quest_reg, name, -1) }
# Quest.objective(quest_name, kind, target, need) — add an objective.
@Namespace(Quest) function quest_objective(rpg_st: mut RpgState, quest_name: pointer, kind: int, target: int, need: int) -> int {
  let qid = quest_id(rpg_st, quest_name)
  if qid < 0 { return -1 }
  if rpg_st.obj_n >= OBJ_MAX { return -1 }
  let id = rpg_st.obj_n
  rpg_st.obj_qid[id] = qid;  rpg_st.obj_kind[id] = kind;  rpg_st.obj_target[id] = target
  rpg_st.obj_need[id] = need;  rpg_st.obj_have[id] = 0
  rpg_st.obj_n += 1
  return id
}
# Quest.start(name) — activate a quest (emits QuestStarted).
@Namespace(Quest) function quest_start(rpg_st: mut RpgState, name: pointer) -> void {
  let qid = quest_id(rpg_st, name)
  if qid < 0 { return }
  rpg_st.quest_state[qid] = 2
  emit QuestStarted(quest: qid)
}
@Namespace(Quest) function quest_state_of(rpg_st: mut RpgState, name: pointer) -> int {
  let qid = quest_id(rpg_st, name)
  if qid < 0 { return -1 }
  return rpg_st.quest_state[qid]
}

# is every objective of a quest satisfied?
function quest_all_done(rpg_st: RpgState, qid: int) -> int {
  var i = 0
  while i < rpg_st.obj_n {
    if rpg_st.obj_qid[i] == qid { if rpg_st.obj_have[i] < rpg_st.obj_need[i] { return 0 } }
    i += 1
  }
  return 1
}

# Quest.notify(kind, target, amount) — report a gameplay signal. Every ACTIVE
# quest's matching objectives tick up (target 0 on the objective = "any"); a quest
# whose objectives are all met auto-completes.
@Namespace(Quest) function quest_notify(rpg_st: mut RpgState, kind: int, target: int, amount: int) -> void {
  var i = 0
  while i < rpg_st.obj_n {
    let qid = rpg_st.obj_qid[i]
    if rpg_st.quest_state[qid] == 2 {
      if rpg_st.obj_kind[i] == kind {
        if (rpg_st.obj_target[i] == 0) or (rpg_st.obj_target[i] == target) {
          if rpg_st.obj_have[i] < rpg_st.obj_need[i] {
            rpg_st.obj_have[i] += amount
            if rpg_st.obj_have[i] > rpg_st.obj_need[i] { rpg_st.obj_have[i] = rpg_st.obj_need[i] }
            emit ObjectiveProgressed(quest: qid, objective: i, have: rpg_st.obj_have[i], need: rpg_st.obj_need[i])
            if quest_all_done(rpg_st, qid) == 1 {
              rpg_st.quest_state[qid] = 3
              emit QuestCompleted(quest: qid)
            }
          }
        }
      }
    }
    i += 1
  }
}

# ---- global flag store (branching / world state) --------------------------
@Namespace(Quest) function quest_flag(rpg_st: mut RpgState, name: pointer, value: int) -> void { Dict.set(rpg_st.quest_flags, name, value) }
@Namespace(Quest) function quest_flag_get(rpg_st: mut RpgState, name: pointer) -> int { return Dict.get_or(rpg_st.quest_flags, name, 0) }