////
// Bead of Force
// Created by Solias (sorcerer@wnwn.net)
// http://www.wnwn.net/
//
// This script implements the unique power for the bead of force item.
// Include it into your item handler and call the functions below
//
//

// actions to be taken by the creature on a bounce
// loc is the location to bounce to.
void wi_bounce_creature(location loc);


// calculate where a creature should land after a blast
// creature - location of creature hit by blast
// blast - blast point
// blast_strength - maximum distance to throw creature
// max_range - if you want to use a linear fall-off function to determine how far to throw
//             the creatures then set this value to the maximum blast radius, if you want to
//             blast all creatures with the same force then set this value to 0.0 (the default).
//             blast_strength should be less than max range or the effects may look strange.
location wi_calculate_blast(location creature, location blast, float blast_strength=3.0, float max_range=0.0);


// This function will apply the bead of force effect at the given location
// self is the location of the user, target is the target he chose.
void wi_bof_effect(object self, location target);


// actions to be taken by the creature on a bounce
void wi_bounce_creature(location loc) {
    ClearAllActions();
    JumpToLocation(loc);
    ActionDoCommand(SetCommandable(TRUE));
    SetCommandable(FALSE);
}

// calculate where a creature should land after a blast
location wi_calculate_blast(location creature, location blast, float blast_strength, float max_range=0.0) {

     // Calculate the direction vector from blast through creature
     vector vc = GetPositionFromLocation(creature);
     vector vb = GetPositionFromLocation(blast);
     vector dv = vc - vb;

     float blast_distance = VectorMagnitude(dv);

     // Calculate blast strength (linear fall-off):
     if(max_range > 0.0) {

          // Case 1: target out of blast range
          if(blast_distance >= max_range) blast_strength = 0.0;

          // Case 2: Target at blast point
          // In this case just choose a random direction to blast the creature.
          // Use maximum strength
          else if(blast_distance <= 0.0)  dv = AngleToVector(IntToFloat(Random(360)));

          // Case 3: Target in range
          else {
               blast_distance = (max_range - blast_distance) / max_range;
               blast_strength = blast_strength * blast_distance;
          }
     }

     // Even if we are not using linear fall-off we still need to avoid degenerate vectors
     else if(blast_distance <= 0.0)  dv = AngleToVector(IntToFloat(Random(360)));

     // Normalize the vector since all we want is direction
     dv = VectorNormalize(dv);

     // Calculate final displacement vector
     dv = (dv * blast_strength);

     // Return the new location
     return Location(GetAreaFromLocation(creature), vc + dv, GetFacingFromLocation(creature));
}


// This function will apply the bead of force effect at the given location
void wi_bof_effect(object self, location target) {

     location self_location = GetLocation(self);

     effect bead   = EffectVisualEffect(VFX_FNF_GAS_EXPLOSION_MIND);
     effect blast  = EffectVisualEffect(VFX_FNF_SOUND_BURST);
     effect shake  = EffectVisualEffect(VFX_FNF_SCREEN_BUMP);
     effect field  = EffectVisualEffect(VFX_DUR_GLOBE_INVULNERABILITY);
     effect impact = EffectVisualEffect(VFX_IMP_SUNSTRIKE);
     effect strike = EffectVisualEffect(VFX_IMP_KNOCK);
     effect damage = EffectDamage(d6(5),DAMAGE_TYPE_BLUDGEONING);
     effect hold   = EffectParalyze();
     effect immune_blunt  = EffectDamageResistance(DAMAGE_TYPE_BLUDGEONING, 60);
     effect immune_pierce = EffectDamageResistance(DAMAGE_TYPE_PIERCING, 60);
     effect immune_slash  = EffectDamageResistance(DAMAGE_TYPE_SLASHING, 60);

     float fDist = GetDistanceBetweenLocations(self_location, target);
     float fDelay = fDist/(3.0 * log(fDist) + 2.0);

     int object_filter = OBJECT_TYPE_CREATURE | OBJECT_TYPE_DOOR | OBJECT_TYPE_PLACEABLE;
     float blast_radius = 6.0;

     // Create moving bead visual
     ApplyEffectAtLocation(DURATION_TYPE_INSTANT, bead, target);

     // Play area blast
     DelayCommand(fDelay, ApplyEffectAtLocation(DURATION_TYPE_INSTANT, blast, target));
     DelayCommand(fDelay, ApplyEffectAtLocation(DURATION_TYPE_INSTANT, shake, target));

     // Find who gets affected
     object target_object = GetFirstObjectInShape(SHAPE_SPHERE, blast_radius, target, TRUE, object_filter);

     while(target_object != OBJECT_INVALID) {

           if(!GetIsReactionTypeFriendly(target_object, self)) {
               // Damage them
               DelayCommand(fDelay + 0.5, ApplyEffectToObject(DURATION_TYPE_INSTANT, damage, target_object));
               DelayCommand(fDelay + 0.5, ApplyEffectToObject(DURATION_TYPE_INSTANT, impact, target_object));

               // Creatures only
               if(GetObjectType(target_object) == OBJECT_TYPE_CREATURE) {

                    // Blast them away from impact point
                    location landing_point = wi_calculate_blast(GetLocation(target_object), target, 7.0, 6.5);
                    DelayCommand(fDelay + 0.6, AssignCommand(target_object, wi_bounce_creature(landing_point)));

                    // Give them a reflex save and make sure they are not immune to paralysis
                    if(ReflexSave(target_object, 16) == 0 && GetIsImmune(target_object,IMMUNITY_TYPE_PARALYSIS) == 0) {

                         // Trap them in a force sphere
                         float duration = IntToFloat(d6(3)) * 10.0;
                         DelayCommand(fDelay + 0.9, ApplyEffectToObject(DURATION_TYPE_INSTANT, strike, target_object));
                         DelayCommand(fDelay + 1.0, ApplyEffectToObject(DURATION_TYPE_TEMPORARY, field, target_object, duration));
                         DelayCommand(fDelay + 1.0, ApplyEffectToObject(DURATION_TYPE_TEMPORARY, hold, target_object, duration));
                         DelayCommand(fDelay + 1.0, ApplyEffectToObject(DURATION_TYPE_TEMPORARY, immune_blunt, target_object, duration));
                         DelayCommand(fDelay + 1.0, ApplyEffectToObject(DURATION_TYPE_TEMPORARY, immune_pierce, target_object, duration));
                         DelayCommand(fDelay + 1.0, ApplyEffectToObject(DURATION_TYPE_TEMPORARY, immune_slash, target_object, duration));
                    }
               }
           }

           // Get next object
           target_object = GetNextObjectInShape(SHAPE_SPHERE, blast_radius, target, TRUE, object_filter);
     }


}