# crafting.ludic — RPG Module C: a data-driven crafting registry (#59).
#
# Recipes are content, not code: register with Craft.recipe + Craft.ingredient, so a
# game or mod adds crafting with zero code. Craft.make consumes ingredients from the
# ludic.rpg Inventory and yields the output; every step is a veto-able event.

import "ludic.rpg/inventory.ludic"

const CRAFT_MAX: int = 128
const CRAFT_ING_MAX: int = 512

var recipe_reg: Dict = null           # recipe name -> id
var recipe_n: int = 0
var recipe_out: pointers = null       # output item name
var recipe_outqty: words = null
var ing_n: int = 0
var ing_rid:  words = null            # owning recipe id
var ing_name: pointers = null         # ingredient item name
var ing_qty:  words = null

function craft_ensure() -> void {
  if recipe_reg == null {
    recipe_reg = Dict.new()
    recipe_out = bytes(CRAFT_MAX * 8);  recipe_outqty = words(CRAFT_MAX)
    ing_rid = words(CRAFT_ING_MAX);  ing_name = bytes(CRAFT_ING_MAX * 8);  ing_qty = words(CRAFT_ING_MAX)
  }
}

event cancellable CraftRequested { e: int = 0, recipe: int = 0 }
event CraftCompleted { e: int = 0, recipe: int = 0 }

# Craft.recipe(name, out_item, out_qty) — declare a recipe; returns its id.
@Namespace(Craft) function craft_recipe(name: pointer, out_item: pointer, out_qty: int) -> int {
  craft_ensure()
  if recipe_n >= CRAFT_MAX { return 0 - 1 }
  let id = recipe_n
  recipe_out[id] = out_item;  recipe_outqty[id] = out_qty
  recipe_n = recipe_n + 1
  Dict.set(recipe_reg, name, id)
  return id
}
@Namespace(Craft) function craft_id(name: pointer) -> int { craft_ensure();  return Dict.get_or(recipe_reg, name, 0 - 1) }
# Craft.ingredient(recipe_name, item, qty) — add an ingredient requirement.
@Namespace(Craft) function craft_ingredient(recipe_name: pointer, item: pointer, qty: int) -> void {
  craft_ensure()
  let rid = craft_id(recipe_name)
  if rid < 0 { return }
  if ing_n >= CRAFT_ING_MAX { return }
  ing_rid[ing_n] = rid;  ing_name[ing_n] = item;  ing_qty[ing_n] = qty
  ing_n = ing_n + 1
}

# Craft.can(e, recipe_name) — does the owner hold every ingredient?
@Namespace(Craft) function craft_can(e: int, recipe_name: pointer) -> int {
  craft_ensure()
  let rid = craft_id(recipe_name)
  if rid < 0 { return 0 }
  var i = 0
  while i < ing_n {
    if ing_rid[i] == rid {
      if Inventory.count(e, ing_name[i]) < ing_qty[i] { return 0 }
    }
    i = i + 1
  }
  return 1
}

# Craft.make(e, recipe_name) — consume ingredients + produce output; 1 on success.
@Namespace(Craft) function craft_make(e: int, recipe_name: pointer) -> int {
  craft_ensure()
  let rid = craft_id(recipe_name)
  if rid < 0 { return 0 }
  if craft_can(e, recipe_name) == 0 { return 0 }
  if emit CraftRequested(e: e, recipe: rid) != 0 { return 0 }
  var i = 0
  while i < ing_n {
    if ing_rid[i] == rid { Inventory.remove(e, ing_name[i], ing_qty[i]) }
    i = i + 1
  }
  Inventory.add(e, recipe_out[rid], recipe_outqty[rid])
  emit CraftCompleted(e: e, recipe: rid)
  return 1
}