Editing Shopping

What shops can buy and sell, and the prices they charge and pay, are set in "economy" files. These are yaml files, which can contain the entries for multiple shops. For example, spyder_scoops.yaml has the inventories of all the [[Scoop Store]]s in [[The Spyder in the Cathedral]] campaign. 

Here is an example store: 

<pre>
- background: gfx/ui/item/item_menu_bg.png
  items:
  - cost: 50
    slug: repellent
    price: 100
  - cost: 50
    slug: potion
    price: 100
  - cost: 50
    slug: tuxeball
    price: 100
  - cost: 200
    slug: restoration
    price: 400
  - cost: 300
    slug: escape_key
    price: 600
  monsters: []
  resale_multiplier: 0.5
  slug: spyder_cotton_scoop
</pre>

For the shop as a whole:

* background: Is the path to the background sprite. The default is "gfx/ui/item/item_menu_bg.png"
* slug: Unique identifier for the shop itself (example: "spyder_cotton_scoop"). In map files, this slug is used to assign the economy to an NPC and then open the shop when the player interacts with the NPC. The slug must have a translation entry in base.po with msgid = slug.
* items: List of items available in this economy
* monsters: List of monsters available in this economy
* resale_multiplier: When the player sells an item to the shop, the amount the shop pays is the item's default cost times by this number. For example, if the shop's resale_multiplier is 0.5, then the player only gets $50 for selling an item with a value of $100. 

For each item, 

* slug: Slug of the item (must exist in the item database)
* price: How much the player must pay to purchase the item
* cost: How much the player makes from selling the item to that shopkeeper. This over-rules the shop's generic resale_multiplier, so for example you could have a shop pay 50% of value for most items, but 100% of value for certain rare or sought-after items.
* inventory: Quantity available (if unspecified or set to -1, unlimited number available)
* variables: Optional list of GameCondition entries affecting the item (must be non-empty if provided)

Shops can also sell monsters, which works similarly to selling items: 

* slug: Slug of the monster (must exist in the monster database)
* price: How much the player must pay to purchase the item
* cost: How much the player makes from selling the item to that shopkeeper. 
* inventory: Quantity available (if unspecified, only 1 is available)
* level: Minimum level of the monster (must be greater than 0)
* variables: Optional list of GameCondition entries affecting the monster (must be non-empty if provided)

When it comes to map events (see also [[Event Reference Action]]), economies are assigned to an NPC and then interactions with that NPC open the shop:

<pre>
  Create Shopkeeper:
    actions:
    - create_npc spyder_shopassistant,1,6
    - char_face spyder_shopassistant,right
    - set_economy spyder_shopassistant,spyder_flower_scoop
    conditions:
    - not char_exists spyder_shopassistant
    type: event
</pre>

<pre>
  Open Shop 1:
    actions:
    - char_face spyder_shopassistant,right
    - translated_dialog spyder_scoop_welcome
    - open_shop spyder_shopassistant,both_item
    conditions:
    - is char_facing_tile player
    - is button_pressed INTERACT
    type: event
    x: 2
    y: 6
</pre>