/*
 * CSB One In The Chamber
 * Copyright (C) 2026 counter-strike-boost.com
 *
 * The One In The Chamber game mode. Everyone spawns with a knife and a Deagle
 * loaded with a single bullet and no reserve ammo. A kill with the pistol refunds
 * one bullet and a knife kill grants one too, so accuracy keeps you armed; miss
 * and you are down to the knife until you earn another round. Ammo is managed by
 * setting the Deagle's clip on the weapon entity.
 *
 * Inspired by the One In The Chamber game mode. Independent GPL re-implementation.
 *
 * 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>
#include <cstrike>
#include <fun>

new const PLUGIN[] = "CSB One In The Chamber"
new const VERSION[] = "1.0.0"
new const AUTHOR[]  = "counter-strike-boost.com"

new g_pEnabled, g_pStartBullets, g_pKnifeReward

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

    g_pEnabled      = register_cvar("csb_oitc_enabled", "1")
    g_pStartBullets = register_cvar("csb_oitc_startbullets", "1")
    g_pKnifeReward  = register_cvar("csb_oitc_knifereward", "1")

    RegisterHam(Ham_Spawn, "player", "fwSpawnPost", 1)
    register_event("DeathMsg", "eventDeath", "a", "1>0")

    register_clcmd("buy", "blockBuy")
    register_clcmd("buyammo", "blockBuy")
}

public fwSpawnPost(id)
{
    if (!get_pcvar_num(g_pEnabled) || !is_user_alive(id))
        return

    set_task(0.2, "taskEquip", id)
}

public taskEquip(id)
{
    if (!is_user_alive(id))
        return

    strip_user_weapons(id)
    give_item(id, "weapon_knife")
    give_item(id, "weapon_deagle")

    cs_set_user_bpammo(id, CSW_DEAGLE, 0)

    setBullets(id, get_pcvar_num(g_pStartBullets))
}

setBullets(id, count)
{
    new ent = findDeagle(id)

    if (ent > 0)
        cs_set_weapon_ammo(ent, count)

    cs_set_user_bpammo(id, CSW_DEAGLE, 0)
}

addBullet(id)
{
    new ent = findDeagle(id)

    if (ent <= 0)
        return

    new cur = cs_get_weapon_ammo(ent)
    cs_set_weapon_ammo(ent, cur + 1)
    cs_set_user_bpammo(id, CSW_DEAGLE, 0)
}

findDeagle(id)
{
    new ent = 0

    while ((ent = engfunc(EngFunc_FindEntityByString, ent, "classname", "weapon_deagle")) > 0)
    {
        if (pev(ent, pev_owner) == id)
            return ent
    }

    return 0
}

public eventDeath()
{
    if (!get_pcvar_num(g_pEnabled))
        return

    new killer = read_data(1)
    new victim = read_data(2)
    new headshot = read_data(3)

    if (killer < 1 || killer > 32 || killer == victim || !is_user_alive(killer))
        return

    new wpn[32]
    read_data(4, wpn, charsmax(wpn))

    if (containi(wpn, "knife") != -1)
    {
        if (get_pcvar_num(g_pKnifeReward))
        {
            addBullet(killer)
            client_print(killer, print_chat, "[CSB] Knife kill - here is a bullet.")
        }
    }
    else if (containi(wpn, "deagle") != -1)
    {
        addBullet(killer)

        if (headshot)
            client_print(killer, print_chat, "[CSB] Headshot! Bullet refunded.")
        else
            client_print(killer, print_chat, "[CSB] Kill! Bullet refunded.")
    }
}

public blockBuy(id)
{
    if (get_pcvar_num(g_pEnabled))
        return PLUGIN_HANDLED

    return PLUGIN_CONTINUE
}