#include <amxmodx>
#include <amxmisc>
#include <fakemeta>

#pragma semicolon 1

#define PLUGIN "Distance Accuracy"
#define VERSION "1.0"
#define AUTHOR "29th ID"

// Global CVars
new g_cvarDistance, g_cvarOffset;

public plugin_init() {
    register_plugin( PLUGIN, VERSION, AUTHOR );
    
    // Register Hook
    register_forward( FM_TraceLine, "hook_TraceLine", 1 );
    
    // Register CVars
    g_cvarDistance = register_cvar( "trace_distance", "300" );
    g_cvarOffset = register_cvar( "trace_offset", "50" );
}

// The actual hook
//                     start origin    end origin    hit players?  shooter   idoftrace
public hook_TraceLine( Float:start[3], Float:end[3], monsters,      id,         ptr ) {
    
    // Get victim user id
    new victim = get_tr( TR_pHit );
    
    // If the shooter or victim is not alive, exit.
    // (Not a bullet..ie putting mouse over someone and seeing their name)
    if( !is_user_alive( id ) ) return PLUGIN_CONTINUE;
    
    // Grab the maximum distance cvar
    new Float:m_cvarDistance = get_pcvar_float( g_cvarDistance );
    
    // Get the distance between "start origin" and "end origin"
    new Float:m_flTraceDistance = vecdist( start, end );
    
    // If start/end distance is greater than the max distance cvar
    if( m_flTraceDistance > m_cvarDistance )
    {
        // Grab the desired offset cvar
        new Float:m_cvarOffset = get_pcvar_float( g_cvarOffset );
        
        // Create a new "end origin" vector
        new Float:m_newend[3];
        
        // Copy the current end origin vector, but add the offset cvar to each line
        m_newend[0] = end[0]+m_cvarOffset;
        m_newend[1] = end[1]+m_cvarOffset;
        m_newend[2] = end[2]+m_cvarOffset;
        
        // Create this trace again, but with the new "end origin", m_newend
        engfunc( EngFunc_TraceLine, start, m_newend, monsters, id, ptr );
        
        // Debug echo
        //client_print( id, print_chat, "Trace: %f > %f", m_flTraceDistance, m_cvarDistance );
        
        return PLUGIN_HANDLED;
    }
    return PLUGIN_CONTINUE;
}

// Space saver for vector distance (distance between two origins)
stock Float:vecdist(Float:vec1[3], Float:vec2[3])
{
        new Float:x = vec1[0] - vec2[0];
        new Float:y = vec1[1] - vec2[1];
        new Float:z = vec1[2] - vec2[2];
        x*=x;
        y*=y;
        z*=z;
        return floatsqroot(x+y+z);
}