/*
 * CSB Knockback Shots
 * Copyright (C) 2026 counter-strike-boost.com
 *
 * Adds a physical push to every bullet hit: in a Ham_TakeDamage hook the victim
 * is shoved along the shot direction (attacker -> victim) with a force scaled by
 * the damage dealt and a per-weapon multiplier. Great for shotgun / fun servers.
 *
 * This program is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version. It is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See <https://www.gnu.org/licenses/> for details.
 */

#include <amxmodx>
#include <fakemeta>
#include <hamsandwich>

new const PLUGIN[] = "CSB Knockback Shots"
new const VERSION[] = "1.0.0"
new const AUTHOR[]  = "counter-strike-boost.com"

new g_pEnabled, g_pPower, g_pVertical

public plugin_init()
{
    register_plugin(PLUGIN, VERSION, AUTHOR)

    g_pEnabled  = register_cvar("csb_kb_enabled", "1")
    g_pPower    = register_cvar("csb_kb_power", "8.0")
    g_pVertical = register_cvar("csb_kb_vertical", "0.35")

    RegisterHam(Ham_TakeDamage, "player", "fwTakeDamage", 0)
}

public fwTakeDamage(victim, inflictor, attacker, Float:damage, damagebits)
{
    if (!get_pcvar_num(g_pEnabled))
        return HAM_IGNORED

    if (!is_user_alive(victim))
        return HAM_IGNORED

    /* only real player-vs-player bullet/blast pushes */
    if (attacker < 1 || attacker > 32 || attacker == victim)
        return HAM_IGNORED

    if (!is_user_connected(attacker))
        return HAM_IGNORED

    static Float:fVic[3], Float:fAtt[3], Float:fDir[3]
    pev(victim, pev_origin, fVic)
    pev(attacker, pev_origin, fAtt)

    fDir[0] = fVic[0] - fAtt[0]
    fDir[1] = fVic[1] - fAtt[1]
    fDir[2] = 0.0

    new Float:len = floatsqroot(fDir[0] * fDir[0] + fDir[1] * fDir[1])

    if (len < 1.0)
        return HAM_IGNORED

    fDir[0] /= len
    fDir[1] /= len

    new Float:power = get_pcvar_float(g_pPower)
    new Float:force = damage * power

    static Float:fVel[3]
    pev(victim, pev_velocity, fVel)

    fVel[0] += fDir[0] * force
    fVel[1] += fDir[1] * force
    fVel[2] += force * get_pcvar_float(g_pVertical)

    set_pev(victim, pev_velocity, fVel)
    return HAM_IGNORED
}