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Bubberstation/code/datums/components/_component.dm
2020-06-10 23:23:50 +02:00

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/**
* # Component
*
* The component datum
*
* A component should be a single standalone unit
* of functionality, that works by receiving signals from it's parent
* object to provide some single functionality (i.e a slippery component)
* that makes the object it's attached to cause people to slip over.
* Useful when you want shared behaviour independent of type inheritance
*/
/datum/component
/**
* Defines how duplicate existing components are handled when added to a datum
*
* See [COMPONENT_DUPE_*][COMPONENT_DUPE_ALLOWED] definitions for available options
*/
var/dupe_mode = COMPONENT_DUPE_HIGHLANDER
/**
* The type to check for duplication
*
* `null` means exact match on `type` (default)
*
* Any other type means that and all subtypes
*/
var/dupe_type
/// The datum this components belongs to
var/datum/parent
/**
* Only set to true if you are able to properly transfer this component
*
* At a minimum [RegisterWithParent][/datum/component/proc/RegisterWithParent] and [UnregisterFromParent][/datum/component/proc/UnregisterFromParent] should be used
*
* Make sure you also implement [PostTransfer][/datum/component/proc/PostTransfer] for any post transfer handling
*/
var/can_transfer = FALSE
/**
* Create a new component.
*
* Additional arguments are passed to [Initialize()][/datum/component/proc/Initialize]
*
* Arguments:
* * datum/P the parent datum this component reacts to signals from
*/
/datum/component/New(list/raw_args)
parent = raw_args[1]
var/list/arguments = raw_args.Copy(2)
if(Initialize(arglist(arguments)) == COMPONENT_INCOMPATIBLE)
stack_trace("Incompatible [type] assigned to a [parent.type]! args: [json_encode(arguments)]")
qdel(src, TRUE, TRUE)
return
_JoinParent(parent)
/**
* Called during component creation with the same arguments as in new excluding parent.
*
* Do not call `qdel(src)` from this function, `return COMPONENT_INCOMPATIBLE` instead
*/
/datum/component/proc/Initialize(...)
return
/**
* Properly removes the component from `parent` and cleans up references
*
* Arguments:
* * force - makes it not check for and remove the component from the parent
* * silent - deletes the component without sending a [COMSIG_COMPONENT_REMOVING] signal
*/
/datum/component/Destroy(force=FALSE, silent=FALSE)
if(!force && parent)
_RemoveFromParent()
if(!silent)
SEND_SIGNAL(parent, COMSIG_COMPONENT_REMOVING, src)
parent = null
return ..()
/**
* Internal proc to handle behaviour of components when joining a parent
*/
/datum/component/proc/_JoinParent()
var/datum/P = parent
//lazy init the parent's dc list
var/list/dc = P.datum_components
if(!dc)
P.datum_components = dc = list()
//set up the typecache
var/our_type = type
for(var/I in _GetInverseTypeList(our_type))
var/test = dc[I]
if(test) //already another component of this type here
var/list/components_of_type
if(!length(test))
components_of_type = list(test)
dc[I] = components_of_type
else
components_of_type = test
if(I == our_type) //exact match, take priority
var/inserted = FALSE
for(var/J in 1 to components_of_type.len)
var/datum/component/C = components_of_type[J]
if(C.type != our_type) //but not over other exact matches
components_of_type.Insert(J, I)
inserted = TRUE
break
if(!inserted)
components_of_type += src
else //indirect match, back of the line with ya
components_of_type += src
else //only component of this type, no list
dc[I] = src
RegisterWithParent()
/**
* Internal proc to handle behaviour when being removed from a parent
*/
/datum/component/proc/_RemoveFromParent()
var/datum/P = parent
var/list/dc = P.datum_components
for(var/I in _GetInverseTypeList())
var/list/components_of_type = dc[I]
if(length(components_of_type)) //
var/list/subtracted = components_of_type - src
if(subtracted.len == 1) //only 1 guy left
dc[I] = subtracted[1] //make him special
else
dc[I] = subtracted
else //just us
dc -= I
if(!dc.len)
P.datum_components = null
UnregisterFromParent()
/**
* Register the component with the parent object
*
* Use this proc to register with your parent object
*
* Overridable proc that's called when added to a new parent
*/
/datum/component/proc/RegisterWithParent()
return
/**
* Unregister from our parent object
*
* Use this proc to unregister from your parent object
*
* Overridable proc that's called when removed from a parent
* *
*/
/datum/component/proc/UnregisterFromParent()
return
/**
* Register to listen for a signal from the passed in target
*
* This sets up a listening relationship such that when the target object emits a signal
* the source datum this proc is called upon, will receive a callback to the given proctype
* Return values from procs registered must be a bitfield
*
* Arguments:
* * datum/target The target to listen for signals from
* * sig_type_or_types Either a string signal name, or a list of signal names (strings)
* * proctype The proc to call back when the signal is emitted
* * override If a previous registration exists you must explicitly set this
*/
/datum/proc/RegisterSignal(datum/target, sig_type_or_types, proctype, override = FALSE)
if(QDELETED(src) || QDELETED(target))
return
var/list/procs = signal_procs
if(!procs)
signal_procs = procs = list()
if(!procs[target])
procs[target] = list()
var/list/lookup = target.comp_lookup
if(!lookup)
target.comp_lookup = lookup = list()
var/list/sig_types = islist(sig_type_or_types) ? sig_type_or_types : list(sig_type_or_types)
for(var/sig_type in sig_types)
if(!override && procs[target][sig_type])
stack_trace("[sig_type] overridden. Use override = TRUE to suppress this warning")
procs[target][sig_type] = proctype
if(!lookup[sig_type]) // Nothing has registered here yet
lookup[sig_type] = src
else if(lookup[sig_type] == src) // We already registered here
continue
else if(!length(lookup[sig_type])) // One other thing registered here
lookup[sig_type] = list(lookup[sig_type]=TRUE)
lookup[sig_type][src] = TRUE
else // Many other things have registered here
lookup[sig_type][src] = TRUE
signal_enabled = TRUE
/**
* Stop listening to a given signal from target
*
* Breaks the relationship between target and source datum, removing the callback when the signal fires
*
* Doesn't care if a registration exists or not
*
* Arguments:
* * datum/target Datum to stop listening to signals from
* * sig_typeor_types Signal string key or list of signal keys to stop listening to specifically
*/
/datum/proc/UnregisterSignal(datum/target, sig_type_or_types)
var/list/lookup = target.comp_lookup
if(!signal_procs || !signal_procs[target] || !lookup)
return
if(!islist(sig_type_or_types))
sig_type_or_types = list(sig_type_or_types)
for(var/sig in sig_type_or_types)
if(!signal_procs[target][sig])
continue
switch(length(lookup[sig]))
if(2)
lookup[sig] = (lookup[sig]-src)[1]
if(1)
stack_trace("[target] ([target.type]) somehow has single length list inside comp_lookup")
if(src in lookup[sig])
lookup -= sig
if(!length(lookup))
target.comp_lookup = null
break
if(0)
lookup -= sig
if(!length(lookup))
target.comp_lookup = null
break
else
lookup[sig] -= src
signal_procs[target] -= sig_type_or_types
if(!signal_procs[target].len)
signal_procs -= target
/**
* Called on a component when a component of the same type was added to the same parent
*
* See [/datum/component/var/dupe_mode]
*
* `C`'s type will always be the same of the called component
*/
/datum/component/proc/InheritComponent(datum/component/C, i_am_original)
return
/**
* Called on a component when a component of the same type was added to the same parent with [COMPONENT_DUPE_SELECTIVE]
*
* See [/datum/component/var/dupe_mode]
*
* `C`'s type will always be the same of the called component
*
* return TRUE if you are absorbing the component, otherwise FALSE if you are fine having it exist as a duplicate component
*/
/datum/component/proc/CheckDupeComponent(datum/component/C, ...)
return
/**
* Callback Just before this component is transferred
*
* Use this to do any special cleanup you might need to do before being deregged from an object
*/
/datum/component/proc/PreTransfer()
return
/**
* Callback Just after a component is transferred
*
* Use this to do any special setup you need to do after being moved to a new object
*
* Do not call `qdel(src)` from this function, `return COMPONENT_INCOMPATIBLE` instead
*/
/datum/component/proc/PostTransfer()
return COMPONENT_INCOMPATIBLE //Do not support transfer by default as you must properly support it
/**
* Internal proc to create a list of our type and all parent types
*/
/datum/component/proc/_GetInverseTypeList(our_type = type)
//we can do this one simple trick
var/current_type = parent_type
. = list(our_type, current_type)
//and since most components are root level + 1, this won't even have to run
while (current_type != /datum/component)
current_type = type2parent(current_type)
. += current_type
/**
* Internal proc to handle most all of the signaling procedure
*
* Will runtime if used on datums with an empty component list
*
* Use the [SEND_SIGNAL] define instead
*/
/datum/proc/_SendSignal(sigtype, list/arguments)
var/target = comp_lookup[sigtype]
if(!length(target))
var/datum/C = target
if(!C.signal_enabled)
return NONE
var/proctype = C.signal_procs[src][sigtype]
return NONE | CallAsync(C, proctype, arguments)
. = NONE
for(var/I in target)
var/datum/C = I
if(!C.signal_enabled)
continue
var/proctype = C.signal_procs[src][sigtype]
. |= CallAsync(C, proctype, arguments)
// The type arg is casted so initial works, you shouldn't be passing a real instance into this
/**
* Return any component assigned to this datum of the given type
*
* This will throw an error if it's possible to have more than one component of that type on the parent
*
* Arguments:
* * datum/component/c_type The typepath of the component you want to get a reference to
*/
/datum/proc/GetComponent(datum/component/c_type)
RETURN_TYPE(c_type)
if(initial(c_type.dupe_mode) == COMPONENT_DUPE_ALLOWED || initial(c_type.dupe_mode) == COMPONENT_DUPE_SELECTIVE)
stack_trace("GetComponent was called to get a component of which multiple copies could be on an object. This can easily break and should be changed. Type: \[[c_type]\]")
var/list/dc = datum_components
if(!dc)
return null
. = dc[c_type]
if(length(.))
return .[1]
// The type arg is casted so initial works, you shouldn't be passing a real instance into this
/**
* Return any component assigned to this datum of the exact given type
*
* This will throw an error if it's possible to have more than one component of that type on the parent
*
* Arguments:
* * datum/component/c_type The typepath of the component you want to get a reference to
*/
/datum/proc/GetExactComponent(datum/component/c_type)
RETURN_TYPE(c_type)
if(initial(c_type.dupe_mode) == COMPONENT_DUPE_ALLOWED || initial(c_type.dupe_mode) == COMPONENT_DUPE_SELECTIVE)
stack_trace("GetComponent was called to get a component of which multiple copies could be on an object. This can easily break and should be changed. Type: \[[c_type]\]")
var/list/dc = datum_components
if(!dc)
return null
var/datum/component/C = dc[c_type]
if(C)
if(length(C))
C = C[1]
if(C.type == c_type)
return C
return null
/**
* Get all components of a given type that are attached to this datum
*
* Arguments:
* * c_type The component type path
*/
/datum/proc/GetComponents(c_type)
var/list/dc = datum_components
if(!dc)
return null
. = dc[c_type]
if(!length(.))
return list(.)
/**
* Creates an instance of `new_type` in the datum and attaches to it as parent
*
* Sends the [COMSIG_COMPONENT_ADDED] signal to the datum
*
* Returns the component that was created. Or the old component in a dupe situation where [COMPONENT_DUPE_UNIQUE] was set
*
* If this tries to add a component to an incompatible type, the component will be deleted and the result will be `null`. This is very unperformant, try not to do it
*
* Properly handles duplicate situations based on the `dupe_mode` var
*/
/datum/proc/_AddComponent(list/raw_args)
var/new_type = raw_args[1]
var/datum/component/nt = new_type
var/dm = initial(nt.dupe_mode)
var/dt = initial(nt.dupe_type)
var/datum/component/old_comp
var/datum/component/new_comp
if(ispath(nt))
if(nt == /datum/component)
CRASH("[nt] attempted instantiation!")
else
new_comp = nt
nt = new_comp.type
raw_args[1] = src
if(dm != COMPONENT_DUPE_ALLOWED)
if(!dt)
old_comp = GetExactComponent(nt)
else
old_comp = GetComponent(dt)
if(old_comp)
switch(dm)
if(COMPONENT_DUPE_UNIQUE)
if(!new_comp)
new_comp = new nt(raw_args)
if(!QDELETED(new_comp))
old_comp.InheritComponent(new_comp, TRUE)
QDEL_NULL(new_comp)
if(COMPONENT_DUPE_HIGHLANDER)
if(!new_comp)
new_comp = new nt(raw_args)
if(!QDELETED(new_comp))
new_comp.InheritComponent(old_comp, FALSE)
QDEL_NULL(old_comp)
if(COMPONENT_DUPE_UNIQUE_PASSARGS)
if(!new_comp)
var/list/arguments = raw_args.Copy(2)
arguments.Insert(1, null, TRUE)
old_comp.InheritComponent(arglist(arguments))
else
old_comp.InheritComponent(new_comp, TRUE)
if(COMPONENT_DUPE_SELECTIVE)
var/list/arguments = raw_args.Copy()
arguments[1] = new_comp
var/make_new_component = TRUE
for(var/i in GetComponents(new_type))
var/datum/component/C = i
if(C.CheckDupeComponent(arglist(arguments)))
make_new_component = FALSE
QDEL_NULL(new_comp)
break
if(!new_comp && make_new_component)
new_comp = new nt(raw_args)
else if(!new_comp)
new_comp = new nt(raw_args) // There's a valid dupe mode but there's no old component, act like normal
else if(!new_comp)
new_comp = new nt(raw_args) // Dupes are allowed, act like normal
if(!old_comp && !QDELETED(new_comp)) // Nothing related to duplicate components happened and the new component is healthy
SEND_SIGNAL(src, COMSIG_COMPONENT_ADDED, new_comp)
return new_comp
return old_comp
/**
* Get existing component of type, or create it and return a reference to it
*
* Use this if the item needs to exist at the time of this call, but may not have been created before now
*
* Arguments:
* * component_type The typepath of the component to create or return
* * ... additional arguments to be passed when creating the component if it does not exist
*/
/datum/proc/LoadComponent(component_type, ...)
. = GetComponent(component_type)
if(!.)
return _AddComponent(args)
/**
* Removes the component from parent, ends up with a null parent
*/
/datum/component/proc/RemoveComponent()
if(!parent)
return
var/datum/old_parent = parent
PreTransfer()
_RemoveFromParent()
parent = null
SEND_SIGNAL(old_parent, COMSIG_COMPONENT_REMOVING, src)
/**
* Transfer this component to another parent
*
* Component is taken from source datum
*
* Arguments:
* * datum/component/target Target datum to transfer to
*/
/datum/proc/TakeComponent(datum/component/target)
if(!target || target.parent == src)
return
if(target.parent)
target.RemoveComponent()
target.parent = src
var/result = target.PostTransfer()
switch(result)
if(COMPONENT_INCOMPATIBLE)
var/c_type = target.type
qdel(target)
CRASH("Incompatible [c_type] transfer attempt to a [type]!")
if(target == AddComponent(target))
target._JoinParent()
/**
* Transfer all components to target
*
* All components from source datum are taken
*
* Arguments:
* * /datum/target the target to move the components to
*/
/datum/proc/TransferComponents(datum/target)
var/list/dc = datum_components
if(!dc)
return
var/comps = dc[/datum/component]
if(islist(comps))
for(var/datum/component/I in comps)
if(I.can_transfer)
target.TakeComponent(I)
else
var/datum/component/C = comps
if(C.can_transfer)
target.TakeComponent(comps)
/**
* Return the object that is the host of any UI's that this component has
*/
/datum/component/ui_host()
return parent