Ticket #999: #999-2012-03-19.patch

binaries/data/mods/public/art/actors/units/carthaginians/healer.xml

@@ -8 +8 @@
         <animation file="female/f_walk_01.dae" name="Walk" speed="30"/>
         <animation file="female/f_walk_01.dae" name="Run" speed="45"/>
         <animation file="female/f_death_01.dae" name="Death" speed="100"/>
+        <animation file="female/f_salute_01.dae" name="Heal" speed="30"/>
       </animations>
       <props>
         <prop actor="props/units/heads/head_kart_priestess.xml" attachpoint="head"/>

binaries/data/mods/public/art/actors/units/celts/healer.xml

@@ -8 +8 @@
         <animation file="biped/inf_staff_walk_a.dae" name="Walk" speed="20"/>
         <animation file="infantry/general/death/inf_01.psa" name="Death" speed="400"/>
         <animation file="biped/inf_staff_walk_a.dae" name="Run" speed="40"/>
+        <animation file="female/f_salute_01.dae" name="Heal" speed="30"/>
       </animations>
       <mesh>skeletal/m_dress_cuffs.dae</mesh>
       <props>

binaries/data/mods/public/art/actors/units/hellenes/healer.xml

@@ -7 +7 @@
         <animation file="biped/inf_staff_idle_a.dae" name="Idle" speed="200"/>
         <animation file="biped/inf_staff_walk_a.dae" name="Walk" speed="20"/>
         <animation file="infantry/general/death/inf_01.psa" name="Death" speed="400"/>
+        <animation file="female/f_salute_01.dae" name="Heal" speed="30"/>
       </animations>
       <mesh>skeletal/m_dress_a.pmd</mesh>
       <props>

binaries/data/mods/public/art/actors/units/iberians/healer.xml

@@ -8 +8 @@
         <animation file="female/f_walk_01.dae" name="Walk" speed="30"/>
         <animation file="female/f_walk_01.dae" name="Run" speed="45"/>
         <animation file="female/f_death_01.dae" name="Death" speed="120"/>
+        <animation file="female/f_salute_01.dae" name="Heal" speed="30"/>
       </animations>
       <props>
         <prop actor="props/units/heads/head_iber_healer.xml" attachpoint="head"/>

binaries/data/mods/public/art/actors/units/persians/healer.xml

@@ -7 +7 @@
         <animation file="biped/inf_staff_idle_a.dae" name="Idle" speed="200"/>
         <animation file="biped/inf_staff_walk_a.dae" name="Walk" speed="20"/>
         <animation file="infantry/general/death/inf_01.psa" name="Death" speed="400"/>
+        <animation file="female/f_salute_01.dae" name="Heal" speed="30"/>
       </animations>
       <mesh>skeletal/m_dress_cuffs.dae</mesh>
       <props>

binaries/data/mods/public/art/actors/units/romans/healer.xml

@@ -8 +8 @@
         <animation file="biped/inf_staff_walk_a.dae" name="Walk" speed="20"/>
         <animation file="biped/inf_staff_walk_a.dae" name="Run" speed="20"/>
         <animation file="infantry/general/death/inf_01.psa" name="Death" speed="400"/>
+        <animation file="female/f_salute_01.dae" name="Heal" speed="30"/>
       </animations>
       <mesh>skeletal/m_dress_a.pmd</mesh>
       <props>

binaries/data/mods/public/art/textures/cursors/action-heal.txt

@@ +1 @@
+1 1

binaries/data/mods/public/gui/session/input.js

@@ -297 +297 @@
                 return {"possible": true, "tooltip": tooltip};
             }
             break;
+        case "heal":
+            // The check if the target is unhealable is done by targetState.needsHeal
+            if (entState.Healer && isUnit(targetState) && targetState.needsHeal && (playerOwned || allyOwned))
+            {
+                var unhealableClasses = entState.Healer.unhealableClasses;
+                for each (var unitClass in targetState.identity.classes)
+                {
+                    if (unhealableClasses.indexOf(unitClass) != -1)
+                    {
+                        return {"possible": false};
+                    }
+                }
+                
+                var healableClasses = entState.Healer.healableClasses;
+                for each (var unitClass in targetState.identity.classes)
+                {
+                    if (healableClasses.indexOf(unitClass) != -1)
+                    {
+                        return {"possible": true};
+                    }
+                }
+            }
+            break;
         case "gather":
             if (targetState.resourceSupply && (playerOwned || gaiaOwned))
             {
@@ -417 +440 @@
             return {"type": "build", "cursor": "action-repair", "target": target};
         else if ((actionInfo = getActionInfo("set-rallypoint", target)).possible)
             return {"type": "set-rallypoint", "cursor": actionInfo.cursor, "data": actionInfo.data, "position": actionInfo.position};
+        else if (getActionInfo("heal", target).possible)
+            return {"type": "heal", "cursor": "action-heal", "target": target};
         else if (getActionInfo("attack", target).possible)
             return {"type": "attack", "cursor": "action-attack", "target": target};
         else if (getActionInfo("unset-rallypoint", target).possible)
@@ -1037 +1062 @@
         Engine.GuiInterfaceCall("PlaySound", { "name": "order_attack", "entity": selection[0] });
         return true;
 
+    case "heal":
+        Engine.PostNetworkCommand({"type": "heal", "entities": selection, "target": action.target, "queued": queued});
+        // TODO: Play a sound?
+//      Engine.GuiInterfaceCall("PlaySound", { "name": "order_heal", "entity": selection[0] });
+        return true;
+
     case "build": // (same command as repair)
     case "repair":
         Engine.PostNetworkCommand({"type": "repair", "entities": selection, "target": action.target, "autocontinue": true, "queued": queued});

binaries/data/mods/public/gui/session/selection_details.js

@@ -74 +74 @@
         experienceSize.rtop = 100 - 100 * Math.max(0, Math.min(1, 1.0 * entState.promotion.curr / entState.promotion.req));
         experienceBar.size = experienceSize;
  
-        var experience = "[font=\"serif-bold-13\"]Experience [/font]" + entState.promotion.curr;
+        var experience = "[font=\"serif-bold-13\"]Experience [/font]" + Math.floor(entState.promotion.curr);
         if (entState.promotion.curr < entState.promotion.req)
             experience += "/" + entState.promotion.req;
         getGUIObjectByName("experience").tooltip = experience;

binaries/data/mods/public/simulation/components/GarrisonHolder.js

@@ -320 +320 @@
             var cmpHealth = Engine.QueryInterface(entity, IID_Health);
             if (cmpHealth)
             {
-                if (cmpHealth.GetHitpoints() < cmpHealth.GetMaxHitpoints())
+                // We do not want to heal unhealable units
+                if (!cmpHealth.IsUnhealable())
                     cmpHealth.Increase(this.healRate);
             }
         }

binaries/data/mods/public/simulation/components/GuiInterface.js

@@ -155 +155 @@
         ret.hitpoints = cmpHealth.GetHitpoints();
         ret.maxHitpoints = cmpHealth.GetMaxHitpoints();
         ret.needsRepair = cmpHealth.IsRepairable() && (cmpHealth.GetHitpoints() < cmpHealth.GetMaxHitpoints());
+        ret.needsHeal = !cmpHealth.IsUnhealable();
     }
 
     var cmpAttack = Engine.QueryInterface(ent, IID_Attack);
@@ -273 +274 @@
         ret.barterMarket = { "prices": cmpBarter.GetPrices() };
     }
 
+    var cmpHeal = Engine.QueryInterface(ent, IID_Heal);
+    if (cmpHeal)
+    {
+        ret.Healer = { 
+            "unhealableClasses": cmpHeal.GetUnhealableClasses(),
+            "healableClasses": cmpHeal.GetHealableClasses(),
+        };
+    }
+
     var cmpRangeManager = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
     ret.visibility = cmpRangeManager.GetLosVisibility(ent, player, false);
 

binaries/data/mods/public/simulation/components/Heal.js

@@ +1 @@
+function Heal() {}
+
+Heal.prototype.Schema = 
+    "<a:help>Controls the healing abilities of the unit.</a:help>" +
+    "<a:example>" +
+        "<Range>20</Range>" +
+        "<HP>5</HP>" +
+        "<Rate>2000</Rate>" +
+        "<UnhealableClasses datatype=\"tokens\">Cavalry</UnhealableClasses>" +
+        "<HealableClasses datatype=\"tokens\">Support Infantry</HealableClasses>" +
+    "</a:example>" +
+    "<element name='Range' a:help='Range (in metres) where healing is possible'>" +
+        "<ref name='nonNegativeDecimal'/>" +
+    "</element>" +
+    "<element name='HP' a:help='Hitpoints healed per Rate'>" +
+        "<ref name='nonNegativeDecimal'/>" +
+    "</element>" +
+    "<element name='Rate' a:help='A heal is performed every Rate ms'>" +
+        "<ref name='nonNegativeDecimal'/>" +
+    "</element>" +
+    "<element name='UnhealableClasses' a:help='If the target has any of these classes it can not be healed (even if it has a class from HealableClasses)'>" +
+        "<attribute name='datatype'>" +
+            "<value>tokens</value>" +
+        "</attribute>" +
+        "<text/>" +
+    "</element>" +
+    "<element name='HealableClasses' a:help='The target must have one of these classes to be healable'>" +
+        "<attribute name='datatype'>" +
+            "<value>tokens</value>" +
+        "</attribute>" +
+        "<text/>" +
+    "</element>";
+
+Heal.prototype.Init = function()
+{
+};
+
+Heal.prototype.Serialize = null; // we have no dynamic state to save
+
+Heal.prototype.GetTimers = function()
+{
+    var prepare = 1000;
+    var repeat = +this.template.Rate;
+    return { "prepare": prepare, "repeat": repeat };
+};
+
+Heal.prototype.GetRange = function()
+{
+    var max = +this.template.Range;
+    var min = 0;
+    return { "max": max, "min": min };
+};
+
+Heal.prototype.GetUnhealableClasses = function()
+{
+    var classes = this.template.UnhealableClasses._string;
+    // If we have no unhealable classes defined classes is undefined
+    return classes ? classes.split(/\s+/) : [];
+};
+
+Heal.prototype.GetHealableClasses = function()
+{
+    var classes = this.template.HealableClasses._string;
+    return classes.split(/\s+/);
+};
+
+/**
+ * Heal the target entity. This should only be called after a successful range 
+ * check, and should only be called after GetTimers().repeat msec has passed 
+ * since the last call to PerformHeal.
+ */
+Heal.prototype.PerformHeal = function(target)
+{
+    var cmpHealth = Engine.QueryInterface(target, IID_Health);
+    if (!cmpHealth)
+        return;
+    var targetState = cmpHealth.Increase(Math.max(0,this.template.HP));
+
+    // Add XP
+    var cmpLoot = Engine.QueryInterface(target, IID_Loot);
+    var cmpPromotion = Engine.QueryInterface(this.entity, IID_Promotion);
+    if (targetState!==undefined && cmpLoot && cmpPromotion)
+    {
+        // HP healed * XP per HP
+        cmpPromotion.IncreaseXp((targetState.new-targetState.old)*(cmpLoot.GetXp()/cmpHealth.GetMaxHitpoints()));
+    }
+    //TODO we need a sound file
+//  PlaySound("heal_impact", this.entity);
+};
+
+Engine.RegisterComponentType(IID_Heal, "Heal", Heal);

binaries/data/mods/public/simulation/components/Health.js

@@ -25 +25 @@
             "<value a:help='Remain in the world with 0 health'>remain</value>" +
         "</choice>" +
     "</element>" +
-    "<element name='Healable' a:help='Indicates that the entity can be healed by healer units'>" +
+    "<element name='Unhealable' a:help='Indicates that the entity can not be healed by healer units'>" +
         "<data type='boolean'/>" +
     "</element>" +
     "<element name='Repairable' a:help='Indicates that the entity can be repaired by builder units'>" +
@@ -72 +72 @@
     return (this.template.Repairable == "true");
 };
 
+Health.prototype.IsUnhealable = function()
+{
+    return (this.template.Unhealable == "true"
+        || this.GetHitpoints() <= 0
+        || this.GetHitpoints() >= this.GetMaxHitpoints());
+};
+
 Health.prototype.Kill = function()
 {
     this.Reduce(this.hitpoints);
@@ -131 +138 @@
 {
     // If we're already dead, don't allow resurrection
     if (this.hitpoints == 0)
-        return;
+        return undefined;
 
     var old = this.hitpoints;
     this.hitpoints = Math.min(this.hitpoints + amount, this.GetMaxHitpoints());
 
     Engine.PostMessage(this.entity, MT_HealthChanged, { "from": old, "to": this.hitpoints });
+    // We return the old and the actual hp
+    return { "old": old, "new": this.hitpoints};
 };
 
 //// Private functions ////

binaries/data/mods/public/simulation/components/Loot.js

@@ -21 +21 @@
 
 Loot.prototype.GetXp = function()
 {
-    return this.template.xp;
+    return +(this.template.xp || 0);
 };
 
 Loot.prototype.GetResources = function()

binaries/data/mods/public/simulation/components/UnitAI.js

@@ -139 +139 @@
     "HealthChanged": function(msg) {
         // ignore
     },
+    
+    // TODO: This is part of a really UGLY EVIL HACK
+    "GlobalHealthChanged": function() {
+        // ignore
+    },
 
     "EntityRenamed": function(msg) {
         // ignore
@@ -283 +288 @@
         this.FinishOrder();
     },
 
+    "Order.Heal": function(msg) {
+        // Check the target is alive
+        if (!this.TargetIsAlive(this.order.data.target))
+        {
+            this.FinishOrder();
+            return;
+        }
+
+        // Check if the target is in range
+        if (this.CheckTargetRange(this.order.data.target, IID_Heal))
+        {
+            this.StopMoving();
+            this.SetNextState("INDIVIDUAL.HEAL.HEALING");
+            return;
+        }
+
+        // If we can't reach the target, but are standing ground,
+        // then abandon this heal order
+        if (this.GetStance().respondStandGround && !this.order.data.force)
+        {
+            this.FinishOrder();
+            return;
+        }
+
+        // Try to move within heal range
+        if (this.MoveToTargetRange(this.order.data.target, IID_Heal))
+        {
+            // We've started walking to the given point
+            this.SetNextState("INDIVIDUAL.HEAL.APPROACHING");
+            return;
+        }
+
+        // We can't reach the target, and can't move towards it,
+        // so abandon this heal order
+        this.FinishOrder();
+    },
+
     "Order.Gather": function(msg) {
         
         // If the target is still alive, we need to kill it first
@@ -408 +450 @@
             cmpFormation.Disband();
         },
 
+        "Order.Heal": function(msg) {
+            // TODO: see notes in Order.Attack
+            var cmpFormation = Engine.QueryInterface(this.entity, IID_Formation);
+            cmpFormation.CallMemberFunction("Heal", [msg.data.target, false]);
+            cmpFormation.Disband();
+        },
+
         "Order.Repair": function(msg) {
             // TODO: see notes in Order.Attack
             var cmpFormation = Engine.QueryInterface(this.entity, IID_Formation);
@@ -546 +595 @@
                 // So we'll set a timer here and only report the idle event if we
                 // remain idle
                 this.StartTimer(1000);
+                
+                // TODO: We need to set up a Query that watches own and ally units in LOS
+                // and calls something if they loose health (or change it to simplify)
+                // to replace the really UGLY EVIL HACK using GlobalHealthChanged as that can
+                // have a performance impact as it gets called for each healer for every entity
+                // in the whole map.
+                
+                // If a unit can heal and attack we first want to heal wounded units,
+                // so check if we are a healer and find whether there's anybody nearby to heal.
+                // If anyone approaches later it'll be handled via LosRangeUpdate.)
+                if (this.IsHealer() && this.FindNewHealTargets())
+                    return true; // (abort the FSM transition since we may have already switched state)
 
                 // If we entered the idle state we must have nothing better to do,
                 // so immediately check whether there's anybody nearby to attack.
                 // (If anyone approaches later, it'll be handled via LosRangeUpdate.)
                 if (this.FindNewTargets())
                     return true; // (abort the FSM transition since we may have already switched state)
-
+                
                 // Nobody to attack - stay in idle
                 return false;
             },
@@ -560 +621 @@
             "leave": function() {
                 var rangeMan = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
                 rangeMan.DisableActiveQuery(this.losRangeQuery);
+                if (this.losHealRangeQuery)
+                    rangeMan.DisableActiveQuery(this.losHealRangeQuery);
 
                 this.StopTimer();
 
@@ -569 +632 @@
                     Engine.PostMessage(this.entity, MT_UnitIdleChanged, { "idle": this.isIdle });
                 }
             },
-
+            
+            // TODO: This is part of an really UGLY EVIL HACK
+            "GlobalHealthChanged": function() {
+                if (this.IsHealer())
+                {
+                    this.FindNewHealTargets();
+                }
+            },
+            
             "LosRangeUpdate": function(msg) {
+                if (this.IsHealer())
+                {
+                    // Start healing one of the newly-seen own or ally units (if any)
+                    this.FindNewHealTargets();
+                }
                 if (this.GetStance().targetVisibleEnemies)
                 {
                     // Start attacking one of the newly-seen enemy (if any)
@@ -1000 +1076 @@
             },
         },
 
+        "HEAL": {
+            "EntityRenamed": function(msg) {
+                if (this.order.data.target == msg.entity)
+                    this.order.data.target = msg.newentity;
+            },
+
+            "Attacked": function(msg) {
+                // If we stand ground we will rather die than flee
+                if (!this.GetStance().respondStandGround)
+                    this.Flee(msg.data.attacker, false);
+            },
+
+            "APPROACHING": {
+                "enter": function () {
+                    this.SelectAnimation("move");
+                    this.StartTimer(1000, 1000);
+                },
+
+                "leave": function() {
+                    this.StopTimer();
+                },
+
+                "Timer": function(msg) {
+                    if (this.ShouldAbandonChase(this.order.data.target, this.order.data.force))
+                    {
+                        this.StopMoving();
+                        this.FinishOrder();
+
+                        // Return to our original position
+                        if (this.GetStance().respondHoldGround)
+                            this.WalkToHeldPosition();
+                    }
+                },
+
+                "MoveCompleted": function() {
+                    this.SetNextState("HEALING");
+                },
+
+                "Attacked": function(msg) {
+                    // If we stand ground we will rather die than flee
+                    if (!this.GetStance().respondStandGround)
+                        this.Flee(msg.data.attacker, false);
+                },
+            },
+
+            "HEALING": {
+                "enter": function() {
+                    var cmpHeal = Engine.QueryInterface(this.entity, IID_Heal);
+                    this.healTimers = cmpHeal.GetTimers();
+                    this.SelectAnimation("heal", false, 1.0, "heal");
+                    this.SetAnimationSync(this.healTimers.prepare, this.healTimers.repeat);
+                    this.StartTimer(this.healTimers.prepare, this.healTimers.repeat);
+                    // TODO if .prepare is short, players can cheat by cycling heal/stop/heal
+                    // to beat the .repeat time; should enforce a minimum time
+                    // see comment in ATTACKING.enter
+                    this.FaceTowardsTarget(this.order.data.target);
+                },
+
+                "leave": function() {
+                    this.StopTimer();
+                },
+
+                "Timer": function(msg) {
+                    var target = this.order.data.target;
+                    // Check the target is still alive and healable
+                    if (this.TargetIsAlive(target) && this.CanHeal(target))
+                    {
+                        // Check if we can still reach the target
+                        if (this.CheckTargetRange(target, IID_Heal))
+                        {
+                            this.FaceTowardsTarget(target);
+                            var cmpHeal = Engine.QueryInterface(this.entity, IID_Heal);
+                            cmpHeal.PerformHeal(target);
+                            return;
+                        }
+                        // Can't reach it - try to chase after it
+                        if (this.ShouldChaseTargetedEntity(target, this.order.data.force))
+                        {
+                            if (this.MoveToTargetRange(target, IID_Heal))
+                            {
+                                this.SetNextState("HEAL.CHASING");
+                                return;
+                            }
+                        }
+                    }
+                    // Can't reach it, healed to max hp or doesn't exist any more - give up
+                    if (this.FinishOrder())
+                        return;
+
+                    // Heal another one
+                    if (this.FindNewHealTargets())
+                        return;
+                    
+                    // Return to our original position
+                    if (this.GetStance().respondHoldGround)
+                        this.WalkToHeldPosition();
+                },
+                "Attacked": function(msg) {
+                    // If we stand ground we will rather die than flee
+                    if (!this.GetStance().respondStandGround)
+                        this.Flee(msg.data.attacker, false);
+                },
+            },
+            "CHASING": {
+                "enter": function () {
+                    this.SelectAnimation("move");
+                    this.StartTimer(1000, 1000);
+                },
+
+                "leave": function () {
+                    this.StopTimer();
+                },
+                "Timer": function(msg) {
+                    if (this.ShouldAbandonChase(this.order.data.target, this.order.data.force))
+                    {
+                        this.StopMoving();
+                        this.FinishOrder();
+
+                        // Return to our original position
+                        if (this.GetStance().respondHoldGround)
+                            this.WalkToHeldPosition();
+                    }
+                },
+                "MoveCompleted": function () {
+                    this.SetNextState("HEALING");
+                },
+            },  
+        },
+
         // Returning to dropsite
         "RETURNRESOURCE": {
             "APPROACHING": {
@@ -1473 +1678 @@
     return (this.template.NaturalBehaviour ? true : false);
 };
 
+UnitAI.prototype.IsHealer = function()
+{
+    return Engine.QueryInterface(this.entity, IID_Heal);
+};
+
 UnitAI.prototype.IsIdle = function()
 {
     return this.isIdle;
@@ -1496 +1706 @@
 UnitAI.prototype.OnOwnershipChanged = function(msg)
 {
     this.SetupRangeQuery();
+    if (this.IsHealer())
+        this.SetupHealRangeQuery();
 };
 
 UnitAI.prototype.OnDestroy = function()
@@ -1507 +1719 @@
     var rangeMan = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
     if (this.losRangeQuery)
         rangeMan.DestroyActiveQuery(this.losRangeQuery);
+    if (this.losHealRangeQuery)
+        rangeMan.DestroyActiveQuery(this.losHealRangeQuery);
 };
 
 // Set up a range query for all enemy units within LOS range
@@ -1539 +1753 @@
         }
     }
 
-    var range = this.GetQueryRange();
+    var range = this.GetQueryRange(IID_Attack);
 
     this.losRangeQuery = rangeMan.CreateActiveQuery(this.entity, range.min, range.max, players, IID_DamageReceiver);
     rangeMan.EnableActiveQuery(this.losRangeQuery);
 };
 
+// Set up a range query for all own or ally units within LOS range
+// which can be healed.
+// This should be called whenever our ownership changes.
+UnitAI.prototype.SetupHealRangeQuery = function()
+{
+    var cmpOwnership = Engine.QueryInterface(this.entity, IID_Ownership);
+    var owner = cmpOwnership.GetOwner();
+
+    var rangeMan = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
+    var playerMan = Engine.QueryInterface(SYSTEM_ENTITY, IID_PlayerManager);
+
+    if (this.losHealRangeQuery)
+        rangeMan.DestroyActiveQuery(this.losHealRangeQuery);
+
+    var players = [owner];
+
+    if (owner != -1)
+    {
+        // If unit not just killed, get ally players via diplomacy
+        var cmpPlayer = Engine.QueryInterface(playerMan.GetPlayerByID(owner), IID_Player);
+        var numPlayers = playerMan.GetNumPlayers();
+        for (var i = 1; i < numPlayers; ++i)
+        {
+            // Exclude gaia and enemies
+            if (cmpPlayer.IsAlly(i))
+                players.push(i);
+        }
+    }
+
+    var range = this.GetQueryRange(IID_Heal);
+
+    this.losHealRangeQuery = rangeMan.CreateActiveQuery(this.entity, range.min, range.max, players, IID_Health);
+    rangeMan.EnableActiveQuery(this.losHealRangeQuery);
+};
+
 //// FSM linkage functions ////
 
 UnitAI.prototype.SetNextState = function(state)
@@ -1766 +2015 @@
 
 UnitAI.prototype.OnRangeUpdate = function(msg)
 {
-    if (msg.tag == this.losRangeQuery)
+    if (msg.tag == this.losRangeQuery || msg.tag == this.losHealRangeQuery)
         UnitFsm.ProcessMessage(this, {"type": "LosRangeUpdate", "data": msg});
 };
 
+// really UGLY EVIL HACK
+// TODO This should be replaced with a c++ component that tracks all entities within a range and notifies
+// Healers if any of the entities receives a HealthChanged message.
+// If any entity changes health we call this, so this probably has a huge performance impact.
+UnitAI.prototype.OnGlobalHealthChanged = function(msg)
+{
+    UnitFsm.ProcessMessage(this, {"type": "GlobalHealthChanged"});
+}
+
 //// Helper functions to be called by the FSM ////
 
 UnitAI.prototype.GetWalkSpeed = function()
@@ -2296 +2554 @@
         case "Flee":
         case "LeaveFoundation":
         case "Attack":
+        case "Heal":
         case "Gather":
         case "ReturnResource":
         case "Repair":
@@ -2358 +2617 @@
 {
     if (!this.CanAttack(target))
     {
-        this.WalkToTarget(target, queued);
+        // We don't want to let healers walk to the target unit so they can be easily killed.
+        // Instead we just let them get into healing range.
+        if (this.IsHealer())
+            this.MoveToTargetRange(target, IID_Heal);
+        else
+            this.WalkToTarget(target, queued);
         return;
     }
 
@@ -2419 +2683 @@
     this.AddOrder("GatherNearPosition", { "type": type, "x": x, "z": z }, queued);
 }
 
+UnitAI.prototype.Heal = function(target, queued)
+{
+    if (!this.CanHeal(target))
+    {
+        this.WalkToTarget(target, queued);
+        return;
+    }
+    
+    this.AddOrder("Heal", { "target": target, "force": true }, queued);
+};
+
 UnitAI.prototype.ReturnResource = function(target, queued)
 {
     if (!this.CanReturnResource(target, true))
@@ -2530 +2805 @@
         this.stance = stance;
     else
         error("UnitAI: Setting to invalid stance '"+stance+"'");
-}
+};
 
 UnitAI.prototype.SwitchToStance = function(stance)
 {
@@ -2548 +2823 @@
 
     // Reset the range query, since the range depends on stance
     this.SetupRangeQuery();
-}
+    // Just if we are a healer
+    // TODO maybe move those two to a SetupRangeQuerys()
+    if (this.IsHealer())
+        this.SetupHealRangeQuery();
+};
 
 /**
  * Resets losRangeQuery, and if there are some targets in range that we can
@@ -2569 +2848 @@
     return this.RespondToTargetedEntities(ents);
 };
 
-UnitAI.prototype.GetQueryRange = function()
+/**
+ * Resets losHealRangeQuery, and if there are some targets in range that we can heal
+ * then we start healing and this returns true; otherwise, returns false.
+ */
+UnitAI.prototype.FindNewHealTargets = function()
+{
+    if (!this.losHealRangeQuery)
+        return false;
+    
+    var rangeMan = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
+    var ents = rangeMan.ResetActiveQuery(this.losHealRangeQuery);
+    
+    for each (var ent in ents)
+    {
+        if (this.CanHeal(ent))
+        {
+            this.PushOrderFront("Heal", { "target": ent, "force": false });
+            return true;
+        }
+    }
+    // We haven't found any target to heal
+    return false;
+};
+
+UnitAI.prototype.GetQueryRange = function(iid)
 {
     var ret = { "min": 0, "max": 0 };
     if (this.GetStance().respondStandGround)
     {
-        var cmpRanged = Engine.QueryInterface(this.entity, IID_Attack);
+        var cmpRanged = Engine.QueryInterface(this.entity, iid);
         if (!cmpRanged)
             return ret;
-        var range = cmpRanged.GetRange(cmpRanged.GetBestAttack());
+        var range = iid !== IID_Attack ? cmpRanged.GetRange() : cmpRanged.GetBestAttack();
         ret.min = range.min;
         ret.max = range.max;
     }
@@ -2591 +2894 @@
     }
     else if (this.GetStance().respondHoldGround)
     {
-        var cmpRanged = Engine.QueryInterface(this.entity, IID_Attack);
+        var cmpRanged = Engine.QueryInterface(this.entity, iid);
         if (!cmpRanged)
             return ret;
-        var range = cmpRanged.GetRange(cmpRanged.GetBestAttack());
+        var range = iid !== IID_Attack ? cmpRanged.GetRange() : cmpRanged.GetBestAttack();
         var cmpVision = Engine.QueryInterface(this.entity, IID_Vision);
         if (!cmpVision)
             return ret;
         var halfvision = cmpVision.GetRange() / 2;
         ret.max = range.max + halfvision;
     }
+    // We probably have stance 'passive' and we wouldn't have a range,
+    // but as it is the default for healers we need to set it to something sane.
+    else if (iid === IID_Heal)
+    {
+        var cmpRanged = Engine.QueryInterface(this.entity, iid);
+        if (!cmpRanged)
+            return ret;
+        var range = cmpRanged.GetRange();
+        ret.min = range.min;
+        ret.max = range.max;
+    }
     return ret;
 };
 
@@ -2690 +3004 @@
     return true;
 };
 
+UnitAI.prototype.CanHeal = function(target)
+{
+    // Formation controllers should always respond to commands
+    // (then the individual units can make up their own minds)
+    if (this.IsFormationController())
+        return true;
+
+    // Verify that we're able to respond to Heal commands
+    var cmpHeal = Engine.QueryInterface(this.entity, IID_Heal);
+    if (!cmpHeal)
+        return false;
+
+    // Verify that the target is alive
+    if (!this.TargetIsAlive(target))
+        return false;
+
+    // Verify that the target is owned by the same player as the entity or of an ally
+    var cmpOwnership = Engine.QueryInterface(this.entity, IID_Ownership);
+    if (!cmpOwnership || !(IsOwnedByPlayer(cmpOwnership.GetOwner(), target) || IsOwnedByAllyOfPlayer(cmpOwnership.GetOwner(), target)))
+        return false;
+
+    // Verify that the target is not unhealable (or at max health)
+    var cmpHealth = Engine.QueryInterface(target, IID_Health);
+    if (!cmpHealth || cmpHealth.IsUnhealable())
+        return false;
+
+    // Verify that the target has no unhealable class
+    var cmpIdentity = Engine.QueryInterface(target, IID_Identity);
+    if (!cmpIdentity)
+        return false;
+    for each (var unhealableClass in cmpHeal.GetUnhealableClasses())
+    {
+        if (cmpIdentity.HasClass(unhealableClass) != -1)
+        {
+            return false;
+        }
+    }
+
+    // Verify that the target is a healable class
+    var healable = false;
+    for each (var healableClass in cmpHeal.GetHealableClasses())
+    {
+        if (cmpIdentity.HasClass(healableClass) != -1)
+        {
+            healable = true;
+        }
+    }
+    if (!healable)
+        return false;
+
+    return true;
+};
+
 UnitAI.prototype.CanReturnResource = function(target, checkCarriedResource)
 {
     // Formation controllers should always respond to commands

binaries/data/mods/public/simulation/components/interfaces/Heal.js

@@ +1 @@
+Engine.RegisterInterface("Heal");

binaries/data/mods/public/simulation/components/tests/test_GuiInterface.js

@@ -5 +5 @@
 Engine.LoadComponentScript("interfaces/DamageReceiver.js");
 Engine.LoadComponentScript("interfaces/Foundation.js");
 Engine.LoadComponentScript("interfaces/GarrisonHolder.js");
+Engine.LoadComponentScript("interfaces/Heal.js");
 Engine.LoadComponentScript("interfaces/Health.js");
 Engine.LoadComponentScript("interfaces/Promotion.js");
 Engine.LoadComponentScript("interfaces/RallyPoint.js");
@@ -271 +272 @@
     GetHitpoints: function() { return 50; },
     GetMaxHitpoints: function() { return 60; },
     IsRepairable: function() { return false; },
+    IsUnhealable: function() { return false; },
 });
 
 AddMock(10, IID_Identity, {
@@ -304 +306 @@
     hitpoints: 50,
     maxHitpoints: 60,
     needsRepair: false,
+    needsHeal: true,
     buildEntities: ["test1", "test2"],
     barterMarket: {
         prices: { "buy": {"food":150}, "sell": {"food":25} },

binaries/data/mods/public/simulation/components/tests/test_UnitAI.js

@@ -4 +4 @@
 Engine.LoadComponentScript("interfaces/Attack.js");
 Engine.LoadComponentScript("interfaces/DamageReceiver.js");
 Engine.LoadComponentScript("interfaces/Formation.js");
+Engine.LoadComponentScript("interfaces/Heal.js");
 Engine.LoadComponentScript("interfaces/Health.js");
 Engine.LoadComponentScript("interfaces/ResourceSupply.js");
 Engine.LoadComponentScript("interfaces/Timer.js");

binaries/data/mods/public/simulation/helpers/Commands.js

@@ -66 +66 @@
         });
         break;
 
+    case "heal":
+        if (g_DebugCommands && !(IsOwnedByPlayer(player, cmd.target) || IsOwnedByAllyOfPlayer(player, cmd.target)))
+        {
+            // This check is for debugging only!
+            warn("Invalid command: heal target is not owned by player "+player+" or their ally: "+uneval(cmd));
+        }
+
+        // See UnitAI.CanHeal for target checks
+        var entities = FilterEntityList(cmd.entities, player, controlAllUnits);
+        GetFormationUnitAIs(entities).forEach(function(cmpUnitAI) {
+            cmpUnitAI.Heal(cmd.target, cmd.queued);
+        });
+        break;
+
     case "repair":
         // This covers both repairing damaged buildings, and constructing unfinished foundations
         if (g_DebugCommands && !IsOwnedByAllyOfPlayer(player, cmd.target))

binaries/data/mods/public/simulation/templates/template_structure.xml

@@ -33 +33 @@
   <Health>
     <DeathType>corpse</DeathType>
     <RegenRate>0</RegenRate>
-    <Healable>false</Healable>
+    <Unhealable>true</Unhealable>
     <Repairable>true</Repairable>
   </Health>
   <Identity>

binaries/data/mods/public/simulation/templates/template_unit.xml

@@ -30 +30 @@
     <DeathType>corpse</DeathType>
     <Max>100</Max>
     <RegenRate>0</RegenRate>
-    <Healable>true</Healable>
+    <Unhealable>false</Unhealable>
     <Repairable>false</Repairable>
   </Health>
   <Identity>

binaries/data/mods/public/simulation/templates/template_unit_fauna_hunt_whale.xml

@@ -4 +4 @@
     <Max>100</Max>
     <DeathType>remain</DeathType>
     <RegenRate>1</RegenRate>
-    <Healable>false</Healable>
+    <Unhealable>true</Unhealable>
     <Repairable>false</Repairable>
   </Health>
   <Identity>

binaries/data/mods/public/simulation/templates/template_unit_mechanical.xml

@@ -7 +7 @@
     <SinkAccel>2.0</SinkAccel>
   </Decay>
   <Health>
-    <Healable>false</Healable>
+    <Unhealable>true</Unhealable>
     <Repairable>true</Repairable>
   </Health>
   <Identity>

binaries/data/mods/public/simulation/templates/template_unit_support_healer.xml

@@ -5 +5 @@
     <Pierce>2.0</Pierce>
     <Crush>2.0</Crush>
   </Armour>
-  <Auras>
-    <Heal>
-      <Radius>20</Radius>
-      <Speed>2000</Speed>
-    </Heal>
-  </Auras>
+  <Heal>
+    <Range>30</Range>
+    <HP>5</HP>
+    <Rate>2000</Rate>
+    <UnhealableClasses datatype="tokens"/>
+    <HealableClasses datatype="tokens">Support Infantry Cavalry</HealableClasses>
+  </Heal>
   <Cost>
     <Resources>
       <metal>120</metal>
@@ -23 +24 @@
   <Identity>
     <Classes datatype="tokens">Healer</Classes>
     <GenericName>Healer</GenericName>
-    <Tooltip>Heal units within his Aura. (Not implemented yet)</Tooltip>
+    <Tooltip>Heal units.</Tooltip>
   </Identity>
+  <Promotion>
+    <RequiredXp>100</RequiredXp>
+  </Promotion>
   <Sound>
     <SoundGroups>
       <select>voice/hellenes/civ/civ_male_select.xml</select>

binaries/data/mods/public/simulation/templates/template_unit_support_slave.xml

@@ -36 +36 @@
     </Resources>
   </Cost>
   <Health>
-    <Healable>false</Healable>
+    <Unhealable>true</Unhealable>
   </Health>
   <Identity>
     <Classes datatype="tokens">Slave</Classes>

binaries/data/mods/public/simulation/templates/units/cart_support_healer_b.xml

@@ -6 +6 @@
     <History>Tanit (also spelled TINITH, TINNIT, or TINT), chief goddess of Carthage, equivalent of Astarte. Although she seems to have had some connection with the heavens, she was also a mother goddess, and fertility symbols often accompany representations of her. She was probably the consort of Baal Hammon (or Amon), the chief god of Carthage, and was often given the attribute "face of Baal." Although Tanit did not appear at Carthage before the 5th century BC, she soon eclipsed the more established cult of Baal Hammon and, in the Carthaginian area at least, was frequently listed before him on the monuments. In the worship of Tanit and Baal Hammon, children, probably firstborn, were sacrificed. Ample evidence of the practice has been found west of Carthage in the precinct of Tanit, where a tofet (a sanctuary for the sacrifice of children) was discovered. Tanit was also worshipped on Malta, Sardinia, and in Spain. There is no other reason for giving the Carthaginians a priestess instead of a priest in 0 A.D., although Tanit was the most popular of their two main gods with the people. </History>
     <Tooltip>Heal units within her aura. (Not implemented yet)</Tooltip>
     <Icon>units/cart_support_healer.png</Icon>
+    <Rank>Basic</Rank>
   </Identity>
+  <Promotion>
+    <Entity>units/cart_support_healer_a</Entity>
+  </Promotion>
   <VisualActor>
     <Actor>units/carthaginians/healer.xml</Actor>
   </VisualActor>

binaries/data/mods/public/simulation/templates/units/celt_support_healer_b.xml

@@ -5 +5 @@
     <SpecificName>Druides </SpecificName>
     <History>A druid may be one of many different professions; priest, historian, lawyer, judges, teachers, philosophers, poets, composers, musicians, astronomers, prophets, councillors, high craftsmen like a blacksmith, the classes of the 'men of art', and sometimes kings, chieftains, or other politicians. Druids were very hierarchal, with classes and ranks based on the length of their education and what fields they practiced. They learned their trades through mnemonics by way of poetry and songs, as writing was rarely used by Celts outside of prayers on votive objects, or lists of names for migratory records.</History>
     <Icon>units/celt_support_healer.png</Icon>
+    <Rank>Basic</Rank>
   </Identity>
+  <Promotion>
+    <Entity>units/celt_support_healer_a</Entity>
+  </Promotion>
   <VisualActor>
     <Actor>units/celts/healer.xml</Actor>
   </VisualActor>

binaries/data/mods/public/simulation/templates/units/hele_support_healer_b.xml

@@ -5 +5 @@
     <SpecificName>Hiereús</SpecificName>
     <History>The art of medicine was widely practised in Classical Greece. Hippocrates was the first physician to separate religion and superstition from actual medicine, and many others followed his lead.</History>
     <Icon>units/hele_support_healer.png</Icon>
+    <Rank>Basic</Rank>
   </Identity>
+  <Promotion>
+    <Entity>units/hele_support_healer_a</Entity>
+  </Promotion>
   <VisualActor>
     <Actor>units/hellenes/healer.xml</Actor>
   </VisualActor>

binaries/data/mods/public/simulation/templates/units/iber_support_healer_b.xml

@@ -5 +5 @@
     <SpecificName>Sacerdotisa de Ataekina</SpecificName>
     <History> To the best of our knowledge, only one 'temple'-like structure has been found on the Iberian Peninsula dating from the times and the Iberians worshiped their pantheon of gods at small home altars; however, a very special sculptured head and torso was found in a farmer's field around the turn of the 20th century of a personage who was obviously someone of great substance. As the two principal gods, of the many worshiped, were male Endovellikos and female Ataekina, we thought it would be nice to adopt The Lady of Elche as our priestess-healer representing Ataekina. We know from archelogy and the Romans that Ataekina was associated with spring, the changing of seasons, and nature in general. Ataekina also seems to have been associated with the cycle of birth-death-rebirth.</History>
     <Icon>units/iber_support_healer.png</Icon>
+    <Rank>Basic</Rank>
   </Identity>
+  <Promotion>
+    <Entity>units/iber_support_healer_a</Entity>
+  </Promotion>
   <VisualActor>
     <Actor>units/iberians/healer.xml</Actor>
   </VisualActor>

binaries/data/mods/public/simulation/templates/units/pers_support_healer_b.xml

@@ -6 +6 @@
     <SpecificName>Maguš Mada</SpecificName>
     <History>Under both the Medes and later the Persian the tribe of the Magi or the Magians were the masters of religious and oral tradition, comparable to the Levites of the Bible. They were connected to Zoroastrianism, but likely tended to other Iranian cults as well. Aside from religious duties the Magians also functioned as the Great King's bureaucrats and kept his administration running.</History>
     <Icon>units/pers_support_healer.png</Icon>
+    <Rank>Basic</Rank>
   </Identity>
+  <Promotion>
+    <Entity>units/pers_support_healer_a</Entity>
+  </Promotion>
   <VisualActor>
     <Actor>units/persians/healer.xml</Actor>
   </VisualActor>

binaries/data/mods/public/simulation/templates/units/rome_support_healer_b.xml

@@ -6 +6 @@
     <SpecificName>Pontifex Minoris</SpecificName>
     <History>During the Republic, the position of priest was elevated and required a lot of responsibilities, which is why priests were by no means chosen randomly. The position of Pontifex Maximus, the high priest of the Roman religion, was occupied by such prominent figures as Julius Caesar, Marcus Aemilius Lepidus and Augustus.</History>
     <Icon>units/rome_support_healer.png</Icon>
+    <Rank>Basic</Rank>
   </Identity>
+  <Promotion>
+    <Entity>units/rome_support_healer_a</Entity>
+  </Promotion>
   <VisualActor>
     <Actor>units/romans/healer.xml</Actor>
   </VisualActor>