#include <sourcemod>
#include <sdktools>
#include sdkhooks

#pragma tabsize 0

float GrenadeDamage = 200.0
float PipeBombDamage = 200.0
float BarrelDamage = 200.0

float GrenadeRadius = 50.0
float PipeRadius = 50.0
float BarrelRadius = 50.0

float GrenadeFling = 450.0
float PipeFling = 450.0
float BarrelFling = 450.0

float RadiusFlingGrenade = 100.0
float RadiusFlingPipe = 100.0
float RadiusFlingBarrel = 100.0

float ShakeGrenade = 1000.0
float ShakePipe = 1000.0
float ShakeBarrel = 1000.0

float PowerShakeG = 10.0
float PowerShakeP = 10.0
float PowerShakeB = 10.0

Handle sdkCallPushPlayer;

public OnPluginStart()
{
    Handle GameConf = LoadGameConfigFile("added_explosion-for-survivor");

    if(GameConf == INVALID_HANDLE)
    {
        SetFailState("Couldn't find the offsets and signatures file. Please, check that it is installed correctly.");
    }

    StartPrepSDKCall(SDKCall_Player);
    PrepSDKCall_SetFromConf(GameConf, SDKConf_Signature, "CTerrorPlayer_Fling");
    PrepSDKCall_AddParameter(SDKType_Vector, SDKPass_ByRef);
    PrepSDKCall_AddParameter(SDKType_PlainOldData, SDKPass_Plain);
    PrepSDKCall_AddParameter(SDKType_CBasePlayer, SDKPass_Pointer);
    PrepSDKCall_AddParameter(SDKType_Float, SDKPass_Plain);
    sdkCallPushPlayer = EndPrepSDKCall();
}

bool IsAllow = false;

public OnMapStart()
{
    IsAllow = false;
    CreateTimer(3.0, allow)
}

public Action allow(Handle timer)
{
    IsAllow = true;
}

public void OnEntityDestroyed(int entity)
{
    if(!IsAllow) return;

    if (IsValidEntity(entity) && IsValidEdict(entity))
    {
        char classname[128];
        GetEdictClassname(entity, classname, 128);
        if (StrEqual(classname, "grenade_launcher_projectile", false))
        {
            GrenadeTouch(entity);
        }
        if (StrEqual(classname, "pipe_bomb_projectile", false))
        {
            BombTouch(entity);
        }
        if (StrEqual(classname, "prop_fuel_barrel", false))
        {
            BarrelTouch(entity);
        }
    }
}

public int GrenadeTouch(int entity)
{
    float pos[3];
    GetEntPropVector(entity, PropType:0, "m_vecOrigin", pos, 0);
    GranadeExplode(pos);
}

public int BombTouch(int entity)
{
    float pos[3];
    GetEntPropVector(entity, PropType:0, "m_vecOrigin", pos, 0);
    BombExplode(pos)
}

public int BarrelTouch(int entity)
{
    float pos[3];
    GetEntPropVector(entity, PropType:0, "m_vecOrigin", pos, 0);
    BarrelExplode(pos);
}

int GranadeExplode(float pos[3])
{
    float fDistance = 0.0;
    float pos2[3];
    for( int i = 0; i < 32; i++ )
    {
        if(IsValidClient(i) && GetClientTeam(i) == 2)
        {
            int vClass = GetEntProp(i, Prop_Send, "m_zombieClass")
            if(vClass == 9)
            {
                GetClientAbsOrigin(i, pos2);
                fDistance = GetVectorDistance(pos, pos2);
                if(fDistance < RadiusFlingGrenade && IsVisibleTo(pos, pos2))
                {
                    Fly(i, i, GrenadeFling)
                }
                if(fDistance < GrenadeRadius && IsVisibleTo(pos, pos2))
                {
                    float iOne = GrenadeRadius - fDistance
                    float vForward = GrenadeRadius / iOne
                    int iDamage = RoundToCeil(GrenadeDamage / (vForward * vForward * vForward))
                    float HealBuf = GetEntPropFloat(i, Prop_Send, "m_healthBuffer");
                    int flHealth = GetClientHealth(i)
                    if(RoundToCeil(HealBuf) - iDamage < 0 || flHealth - iDamage < 0 || (RoundToCeil(HealBuf) + flHealth) - iDamage < 0)
                    {
                        int iPoint = RoundToCeil(HealBuf) + flHealth;
                        int iTransit = iPoint - iDamage;
                        SetEntProp(i, Prop_Send, "m_isIncapacitated", 1);
                        ForceDamageEntity(i, iTransit, i)
                    }
                    else
                    {
                        ForceDamageEntity(i, iDamage, i)
                    }
                }
                if(fDistance < ShakeGrenade)
                {
                    float iOne = ShakeGrenade - fDistance
                    float vForward = ShakeGrenade / iOne
                    float iDamage = (PowerShakeG / (vForward * vForward * vForward)) * 1.0
                    ScreenShake(i, iDamage)
                }
            }
        }
    }
}

int BombExplode(float pos[3])
{
    float fDistance = 0.0;
    float pos2[3];
    for( int i = 0; i < 32; i++ )
    {
        if(IsValidClient(i) && GetClientTeam(i) == 2)
        {
            int vClass = GetEntProp(i, Prop_Send, "m_zombieClass")
            if(vClass == 9)
            {
                GetClientAbsOrigin(i, pos2);
                fDistance = GetVectorDistance(pos, pos2);
                if(fDistance < RadiusFlingPipe && IsVisibleTo(pos, pos2))
                {
                    Fly(i, i, PipeFling)
                }
                if(fDistance < PipeRadius && IsVisibleTo(pos, pos2))
                {
                    float iOne = PipeRadius - fDistance
                    float vForward = PipeRadius / iOne
                    int iDamage = RoundToCeil(PipeBombDamage / (vForward * vForward * vForward))
                    float HealBuf = GetEntPropFloat(i, Prop_Send, "m_healthBuffer");
                    int flHealth = GetClientHealth(i)
                    if(RoundToCeil(HealBuf) - iDamage < 0 || flHealth - iDamage < 0 || (RoundToCeil(HealBuf) + flHealth) - iDamage < 0)
                    {
                        int iPoint = RoundToCeil(HealBuf) + flHealth;
                        int iTransit = iPoint - iDamage;
                        SetEntProp(i, Prop_Send, "m_isIncapacitated", 1);
                        ForceDamageEntity(i, iTransit, i)
                    }
                    else
                    {
                        ForceDamageEntity(i, iDamage, i)
                    }
                }
                if(fDistance < ShakePipe)
                {
                    float iOne = ShakePipe - fDistance
                    float vForward = ShakePipe / iOne
                    float iDamage = (PowerShakeP / (vForward * vForward * vForward)) * 1.0
                    ScreenShake(i, iDamage)
                }
            }
        }
    }
}

int BarrelExplode(float pos[3])
{
    float fDistance = 0.0;
    float pos2[3];
    for( int i = 0; i < 32; i++ )
    {
        if(IsValidClient(i) && GetClientTeam(i) == 2)
        {
            int vClass = GetEntProp(i, Prop_Send, "m_zombieClass")
            if(vClass == 9)
            {
                GetClientAbsOrigin(i, pos2);
                fDistance = GetVectorDistance(pos, pos2);
                if(fDistance < RadiusFlingBarrel && IsVisibleTo(pos, pos2))
                {
                    Fly(i, i, BarrelFling)
                }
                if(fDistance < BarrelRadius && IsVisibleTo(pos, pos2))
                {
                    float iOne = BarrelRadius - fDistance
                    float vForward = BarrelRadius / iOne
                    int iDamage = RoundToCeil(BarrelDamage / (vForward * vForward * vForward))
                    float HealBuf = GetEntPropFloat(i, Prop_Send, "m_healthBuffer");
                    int flHealth = GetClientHealth(i)
                    if(RoundToCeil(HealBuf) - iDamage < 0 || flHealth - iDamage < 0 || (RoundToCeil(HealBuf) + flHealth) - iDamage < 0)
                    {
                        int iPoint = RoundToCeil(HealBuf) + flHealth;
                        int iTransit = iPoint - iDamage;
                        SetEntProp(i, Prop_Send, "m_isIncapacitated", 1);
                        ForceDamageEntity(i, iTransit, i)
                    }
                    else
                    {
                        ForceDamageEntity(i, iDamage, i)
                    }
                }
                if(fDistance < ShakeBarrel)
                {
                    float iOne = ShakeBarrel - fDistance
                    float vForward = ShakeBarrel / iOne
                    float iDamage = (PowerShakeB / (vForward * vForward * vForward)) * 1.0
                    ScreenShake(i, iDamage)
                }
            }
        }
    }
}

public Fly(explosion, int target, float power)
{
    if(target <= 0 || !IsValidEntity(target) || !IsValidEdict(target))  return;

    float targetPos[3], explosionPos[3], traceVec[3], resultingFling[3];

    GetEntPropVector(target, Prop_Data, "m_vecOrigin", targetPos);
    GetEntPropVector(explosion, Prop_Data,"m_vecOrigin", explosionPos);

    float fDistance = GetVectorDistance(targetPos, explosionPos)
    float iOne = GrenadeRadius - fDistance
    float iDamage = GrenadeRadius / iOne
    power = (GrenadeDamage / (iDamage * iDamage * iDamage)) * 1.0
    if(power < 1)
        return;

    MakeVectorFromPoints(explosionPos, targetPos, traceVec);
    GetVectorAngles(traceVec, resultingFling);

    resultingFling[0] = Cosine(DegToRad(resultingFling[1])) * power;
    resultingFling[1] = Sine(DegToRad(resultingFling[1])) * power;
    resultingFling[2] = power + (power * 0.5);
    if (GetClientTeam(target) == 2)
    {
        SDKCall(sdkCallPushPlayer, target, resultingFling, 76, target, 2.0);
    }
    else
    {
        SDKCall(sdkCallPushPlayer, target, resultingFling, 2, target, 2.0);
    }
}

public void ScreenShake(int target, float power)
{
    Handle msg;
    msg = StartMessageOne("Shake", target);
    BfWriteByte(msg, 0);
    BfWriteFloat(msg, power);
    BfWriteFloat(msg, 10.0);
    BfWriteFloat(msg, 3.0);
    EndMessage();
}

static bool IsVisibleTo(float position[3], float targetposition[3])
{
    float vAngles[3], vLookAt[3];

    MakeVectorFromPoints(position, targetposition, vLookAt); // compute vector from start to target
    GetVectorAngles(vLookAt, vAngles); // get angles from vector for trace

    // execute Trace
    Handle trace = TR_TraceRayFilterEx(position, vAngles, MASK_SHOT, RayType_Infinite, _TraceFilter);

    bool isVisible = false;
    if (TR_DidHit(trace))
    {
        float vStart[3];
        TR_GetEndPosition(vStart, trace); // retrieve our trace endpoint

        if ((GetVectorDistance(position, vStart, false) + 25.0) >= GetVectorDistance(position, targetposition))
        {
            isVisible = true; // if trace ray length plus tolerance equal or bigger absolute distance, you hit the target
        }
    }

    return isVisible;
}

public bool _TraceFilter(int entity, int contentsMask)
{
    if (!entity || entity <= MaxClients || !IsValidEntity(entity)) // dont let WORLD, or invalid entities be hit
    {
        return false;
    }
    return true;
}
stock void ForceDamageEntity(int causer, int damage, int victim) // thanks to &#36798;&#26031;*&#32500;&#36798;
{
    float victim_origin[3];
    char rupture[32];
    char damage_victim[32];
    IntToString(damage, rupture, sizeof(rupture));
    Format(damage_victim, sizeof(damage_victim), "hurtme%d", victim);
    GetEntPropVector(victim, Prop_Send, "m_vecOrigin", victim_origin);
    int entity = CreateEntityByName("point_hurt");
    DispatchKeyValue(victim, "targetname", damage_victim);
    DispatchKeyValue(entity, "DamageTarget", damage_victim);
    DispatchKeyValue(entity, "Damage", rupture);
    DispatchSpawn(entity);
    TeleportEntity(entity, victim_origin, NULL_VECTOR, NULL_VECTOR);
    AcceptEntityInput(entity, "Hurt", (causer > 0 && causer <= MaxClients) ? causer : -1);
    DispatchKeyValue(entity, "classname", "point_hurt");
    DispatchKeyValue(victim, "targetname", "null");
    AcceptEntityInput(entity, "Kill");
}

stock bool IsValidClient(int client)
{
    if ( client < 1 || client > MaxClients ) return false;
    if( !IsClientInGame(client)) return false;
    if ( !IsPlayerAlive( client )) return false;
    return true;
}