Add power broker, a glowing crystal that sells mana

editor/pickmaps/python

@@ -4,7 +4,7 @@ width 20
 height 20
 msg
 Created:  2019-08-12 Kevin Zheng
-Modified: 2021-07-30 Saiapatsu
+Modified: 2022-05-17 Kevin Zheng
 endmsg
 end
 arch mailbox
@@ -34,6 +34,20 @@ title Python
 slaying /python/IPO/banksay.py
 end
 end
+arch power_crystal
+name power broker
+maxsp 500
+y 4
+no_pick 1
+arch event_say
+title Python
+slaying /python/items/powerbroker.py
+end
+arch event_apply
+title Python
+slaying /python/items/powerbroker.py
+end
+end
 arch messageboard
 x 1
 arch messageboard_say_event

python/items/powerbroker.py

@@ -0,0 +1,144 @@
+"""
+powerbroker.py -- glowing crystals that buy and sell mana
+
+Usage: add an event_apply and event_say to a non-pickable glowing crystal.
+"""
+
+import math
+
+import Crossfire
+import CFItemBroker
+
+N0 = 10000 # initial stock
+P0 = 10 # price per mana in silver at initial stock, N0
+me = Crossfire.WhoAmI()
+
+def charge(payer, quantity):
+    return payer.PayAmount(quantity) == 1
+
+def pay(payee, quantity):
+    # we can't guarentee that the player has any particular type of coin already
+    # so create the object first, then add 1 less than the total.
+    if quantity >= 50:
+        item = payee.CreateObject('platinum coin')
+        CFItemBroker.Item(item).add(int(quantity/50))
+    if quantity % 50 > 0:
+        item = payee.CreateObject('gold coin')
+        CFItemBroker.Item(item).add(int((quantity % 50)/10))
+    if quantity % 50 > 0:
+        item = payee.CreateObject('silver coin')
+        CFItemBroker.Item(item).add(int(quantity % 10))
+
+def on_apply():
+    Crossfire.SetReturnValue(0)
+
+def profit():
+    return 0.1
+
+def mana_stock():
+    stock = Crossfire.GetPrivateDictionary().get('total_mana')
+    if stock is None:
+        stock = N0
+    return stock
+
+def change_stock(amount):
+    Crossfire.GetPrivateDictionary()['total_mana'] = mana_stock() + amount
+
+def base_price(sp):
+    # 1 gold per spell point at nominal stock
+    return sp * P0 * (1 + 1/N0*(N0 - mana_stock()))
+
+def sell_price(sp):
+    return math.floor(base_price(sp)*(1 - profit()))
+
+def buy_price(sp):
+    return max(1, math.ceil(base_price(sp)*(1 + profit())))
+
+def buy_mana():
+    message = Crossfire.WhatIsMessage().lower()
+    try:
+        amount = int(message)
+        max_buy = min(me.MaxSP, mana_stock())
+        if mana_stock() == 0:
+            me.Say("Sorry, we are out of stock right now. Come back later.")
+            return
+        if amount > max_buy:
+            me.Say("I can only sell you up to %d mana right now." % max_buy)
+            amount = max_buy
+        price = buy_price(amount)
+        def do_buy_mana():
+            if charge(Crossfire.WhoIsActivator(), price):
+                me.Say("Bought %d mana for %s." % (amount, Crossfire.CostStringFromValue(price)))
+                me.SP += amount
+                change_stock(-amount)
+            else:
+                me.Say("You can't afford that!")
+        confirm("%d mana would cost you %s. Buy?" % (amount, Crossfire.CostStringFromValue(price)), do_buy_mana)
+    except ValueError:
+        me.Say("How much mana would you like to buy? %d silver per mana point." % buy_price(1))
+
+def sell_mana():
+    message = Crossfire.WhatIsMessage().lower()
+    price = sell_price(me.SP)
+    if price <= 0:
+        me.Say("Sorry, we're not interested in buying mana right now.")
+        return
+
+    def do_sell_mana():
+        me.Say("Sold %d mana for %s." % (me.SP, Crossfire.CostStringFromValue(price)))
+        pay(Crossfire.WhoIsActivator(), price)
+        change_stock(me.SP)
+        me.SP = 0
+    confirm("Sell %d mana for %s?" % (me.SP, Crossfire.CostStringFromValue(price)), do_sell_mana)
+
+def confirm(text, action):
+    me.Say(text)
+    Crossfire.AddReply("yes", "Yes!")
+    Crossfire.AddReply("no", "No, thank you.")
+    Crossfire.GetPrivateDictionary()['confirm_action'] = action
+
+def check_confirm():
+    action = Crossfire.GetPrivateDictionary().get('confirm_action')
+    if action is not None:
+        reply = Crossfire.WhatIsMessage().lower()
+        if reply == "yes":
+            action()
+            del Crossfire.GetPrivateDictionary()['confirm_action']
+        elif reply == "no":
+            me.Say("Thank you, come again!")
+            del Crossfire.GetPrivateDictionary()['confirm_action']
+        else:
+            me.Say("Please answer either 'yes' or 'no'.")
+        return True
+    return False
+
+def status():
+    me.Say("%d mana in stock, buy %d/sell %d silver per mana." % (mana_stock(), buy_price(1), sell_price(1)))
+
+def stock(message):
+    try:
+        qty = int(message.split()[1])
+        change_stock(qty)
+        me.Say("Added %d mana to stock." % qty)
+        status()
+    except Exception:
+        me.Say("I didn't understand that.")
+
+def on_say():
+    if check_confirm():
+        return # don't do anything else
+
+    message = Crossfire.WhatIsMessage().lower()
+    if message == 'status' and Crossfire.WhoIsActivator().DungeonMaster:
+        status()
+    elif message.split()[0] == 'stock' and Crossfire.WhoIsActivator().DungeonMaster:
+        stock(message)
+    elif me.SP > 0:
+        sell_mana()
+    else:
+        buy_mana()
+
+if Crossfire.WhatIsEvent().Subtype == 1:
+    on_apply()
+elif Crossfire.WhatIsEvent().Subtype == 6:
+    on_say()