#include <amxmodx>
#include <amxmisc> //HL Port by SPINX
#include <fakemeta>
#include <xs>

#define PLUGIN  "CS Revo: Gun Drop Effect"
#define VERSION "1.0"
#define AUTHOR  "Wilian M."

#define DROP_GUN_MODEL "models/gundrop.mdl"
#define DROP_GUN_CLASSNAME "drop_gun_ef"

public plugin_init()
{
    register_plugin(PLUGIN, VERSION, AUTHOR)
    
    register_forward(FM_SetModel, "xFwSetModel")
    register_forward(FM_Think, "xFwThink")
    register_forward(FM_Touch, "xFwTouch")
}

public plugin_precache()
{
    precache_model(DROP_GUN_MODEL)
}

public xFwTouch(touched, ent)
{
    if(!pev_valid(ent))
        return FMRES_IGNORED
    
    static xClassName[32]
    pev(ent, pev_classname, xClassName, charsmax(xClassName))
    
    if(equal(xClassName, "weaponbox") || equal(xClassName, DROP_GUN_CLASSNAME))
    {
        xFlatEnt(ent)
    }
    
    return FMRES_IGNORED
}

public xFwThink(ent)
{
    if(!pev_valid(ent))
        return FMRES_IGNORED
    
    static xClassName[32]
    pev(ent, pev_classname, xClassName, charsmax(xClassName))
    
    if(!equal(xClassName, DROP_GUN_CLASSNAME))
        return FMRES_IGNORED

    static xWpn
    xWpn = pev(ent, pev_iuser1)

    if(!pev_valid(xWpn))
    {
        set_pev(ent, pev_flags, pev(ent, pev_flags) | FL_KILLME)

        return FMRES_SUPERCEDE
    }

    set_pev(ent, pev_nextthink, get_gametime())

    return FMRES_IGNORED
}

public xFwSetModel(ent, model[])
{
    if(cstrike_running() && !pev_valid(ent) || cstrike_running() && !equali(model, "models/w_", 8) || cstrike_running() && equali(model, "models/w_weaponbox.mdl"))
        return FMRES_IGNORED
    else if (!pev_valid(ent) || !equali(model, "models/w_", 8))
        return FMRES_IGNORED

    static xClassName[32]
    pev(ent, pev_classname, xClassName, charsmax(xClassName))

    if(!equal(xClassName, "weaponbox"))
        return FMRES_IGNORED

    static xGunDrop
    xGunDrop = engfunc(EngFunc_CreateNamedEntity, engfunc(EngFunc_AllocString, "info_target"))

    if(!pev_valid(xGunDrop))
        return FMRES_IGNORED

    set_pev(xGunDrop, pev_classname, DROP_GUN_CLASSNAME)
    engfunc(EngFunc_SetModel, xGunDrop, DROP_GUN_MODEL)
    set_pev(xGunDrop, pev_iuser1, ent)
    set_pev(xGunDrop, pev_framerate, 1.0)
    set_pev(xGunDrop, pev_animtime, get_gametime())
    set_pev(xGunDrop, pev_movetype, MOVETYPE_FOLLOW)
    set_pev(xGunDrop, pev_aiment, ent)
    set_pev(xGunDrop, pev_nextthink, get_gametime())

    return FMRES_IGNORED
}

stock xFlatEnt(ent)
{
    if(pev(ent, pev_flags) & ~FL_ONGROUND) return
    
    static Float:origin[3], Float:traceto[3], trace = 0, Float:fraction, Float:angles[3], Float:angles2[3]
    
    pev(ent, pev_origin, origin)
    pev(ent, pev_angles, angles)
    
    xs_vec_sub(origin, Float:{0.0, 0.0, 10.0}, traceto)

    engfunc(EngFunc_TraceLine, origin, traceto, IGNORE_MONSTERS, ent, trace)

    get_tr2(trace, TR_flFraction, fraction)

    if(fraction == 1.0) return
    
    static Float:original_forward[3]
    angle_vector(angles, ANGLEVECTOR_FORWARD, original_forward)
    
    static Float:right[3], Float:up[3], Float:fwd[3]
    
    get_tr2(trace, TR_vecPlaneNormal, up)
    
    if(up[2] == 1.0) return
    
    xs_vec_cross(original_forward, up, right)
    xs_vec_cross(up, right, fwd)
    vector_to_angle(fwd, angles)
    vector_to_angle(right, angles2)

    angles[2] = -1.0 * angles2[0]
    
    set_pev(ent, pev_angles, angles)
}