Rework the way triggers and indicators work

Triggers are now a link between link between a datasource (for now only
AuraList) and an indicator (for now only SquareIndicator).

src/types/trigger.lua

@@ -17,47 +17,52 @@
 local omi = select(2, ...)
 local types = omi.GetModule("types")
 
+---
+-- Trigger objects provide a link between indicators and some data source. They
+-- can pass data from the data source into the trigger. This is just a
+-- supertype for all indicators and should not be constructed on its own. It
+-- has no functionality other than providing default implementations that do
+-- nothing.
 types.Trigger = types.CreateClass("Trigger")
 local Trigger = types.Trigger
 
 
--- Constructor for Trigger.
--- fn:
---      The callback function that gets called every time this trigger changes
---      states between active and inactive. Function takes one boolean argument.
-function Trigger:Init(fn)
-    self.fn = fn
+-- Initialize a new Trigger object
+-- indicator:
+--      The indicator that gets activated by this trigger.
+function Trigger:Init(indicator)
+    self.indicator = indicator
 end
 
--- Returns whether the trigger is active
+-- Returns whether or not the trigger is active
 function Trigger:IsActive()
     return false
 end
 
--- Reset the trigger to the default state. Does run the untrigger callback if
--- the trigger is active when Reset is called.
+-- Reset the trigger to the default state. Deactivates the indicator if it is
+-- active when Reset is called.
 function Trigger:Reset()
 end
 
 
+---
+-- AuraTrigger is a trigger that can be attached to AuraList as datasource
 types.AuraTrigger = types.CreateClass("AuraTrigger", Trigger)
 local AuraTrigger = types.AuraTrigger
 
--- Constructor for AuraTrigger
--- fn:
---      The callback function that gets called every time this trigger changes
---      states between active and inactive. Function takes one boolean argument.
---
--- requiredCount = 1:
---      The minimum number of conditions that must be met before the trigger
---      activates. What exactly this means depends on the trigger, examples are
---      # of matching auras, # of stacks. 
---
--- invert = false:
---      If the trigger is inverted it will activate when count < requiredCount.
---      If the trigger is not inverted it will activate when count >= requiredCount.
-function AuraTrigger:Init(fn, spellId, own, requiredCount, invert)
-    Trigger.Init(self, fn)
+--- Initialize a new AuraTrigger object
+-- indicator
+--      Indicator that gets controlled by this trigger.
+-- spellId
+--      Spell id to trigger on
+-- own
+--      Only trigger on auras by the player
+-- requiredCount=1
+--      Number of aura applications to activate trigger
+-- invert=false
+--      Whether to invert trigger activation
+function AuraTrigger:Init(indicator, spellId, own, requiredCount, invert)
+    Trigger.Init(self, indicator)
     self.spellId = spellId
     self.requiredCount = requiredCount or 1
     self.own = own
@@ -65,18 +70,19 @@ function AuraTrigger:Init(fn, spellId, own, requiredCount, invert)
     self.invert = invert or false
 end
 
--- Reset the trigger to the default state. Does run the untrigger callback if
--- the trigger is active when it is called
+--- See Trigger:Reset
 function AuraTrigger:Reset()
     local before = self:IsActive()
     self.count = 0
     local after = self:IsActive()
-    if before ~= after then
-        self.fn(after)
+    if not before and after then
+        self.indicator:Show()
+    elseif before and not after then
+        self.indicator:Hide()
     end
 end
 
--- Return true if the aura matches the trigger
+--- Return true if the aura matches the trigger
 -- aura:
 --      Must be a valid UnitAuraInfo structure.
 function AuraTrigger:IsMatching(aura)
@@ -86,10 +92,10 @@ function AuraTrigger:IsMatching(aura)
     if self.own and aura.sourceUnit ~= "player" then
         return false
     end
-    return true 
+    return true
 end
 
--- Inform the trigger about an added aura
+--- Inform the trigger about an added aura
 -- aura:
 --      Must be a valid UnitAuraInfo
 function AuraTrigger:AddAura(aura)
@@ -98,13 +104,17 @@ function AuraTrigger:AddAura(aura)
     end
     self.count = self.count + 1
 
-    -- Be mindful, this works only if count always changes by 1. 
+    -- Be mindful, this works only if count always changes by 1.
     if self.count == self.requiredCount then
-        self.fn(not self.invert)
+        if self.invert then
+            self.indicator:Hide()
+        else
+            self.indicator:Show()
+        end
     end
 end
 
--- Inform the trigger about an updated aura
+--- Inform the trigger about an updated aura
 -- before:
 --      Must be a valid UnitAuraInfo for the aura before the update
 -- after:
@@ -113,20 +123,25 @@ function AuraTrigger:UpdateAura(before, after)
     --
 end
 
--- Inform the trigger about an aura that got removed
+--- Inform the trigger about an aura that got removed
+-- aura:
 --      Must be a valid UnitAuraInfo for the aura before it got removed
 function AuraTrigger:RemoveAura(aura)
     if not self:IsMatching(aura) then
         return
     end
-    self.count = self.count - 1 
-    -- Be mindful, this works only if count always changes by 1. 
+    self.count = self.count - 1
+    -- Be mindful, this works only if count always changes by 1.
     if self.count == self.requiredCount - 1 then
-        self.fn(self.invert)
+        if self.invert then
+            self.indicator:Show()
+        else
+            self.indicator:Hide()
+        end
     end
 end
 
--- Returns true if the trigger is active, false otherwise
+--- Returns true if the trigger is active, false otherwise
 function AuraTrigger:IsActive()
     if self.invert then
         return self.count < self.requiredCount