source: trunk/src/lua/lua_path.cc @ 319

// Copyright (C) 2012-2014 ChaosForge Ltd
// http://chaosforge.org/
//
// This file is part of NV Libraries.
// For conditions of distribution and use, see copyright notice in nv.hh

#include "nv/lua/lua_path.hh"

#include "nv/lua/lua_raw.hh"

using namespace nv;

lua::path::path( nv::string p )
        : m_count(0), m_path( std::move( p ) )
{
        parse();
}

lua::path::path( const char* p )
        : m_count(0), m_path( p )
{
        parse();
}

lua::path::path( unsigned i )
        : m_count(0)
{
        push( i );
}

void lua::path::parse()
{
        size_t start = 0;
        size_t point = m_path.find('.');

        while( point != std::string::npos )
        {
                push( start, point-start );
                start = point+1;
                point = m_path.find( '.', start );
        }

        push( start, m_path.length() - start );
}

void lua::path::push( size_t e )
{
        m_elements[ m_count ].value  = e;
        m_elements[ m_count ].length = 0;
        m_count++;
}

void lua::path::push( size_t start, size_t length )
{
        m_elements[ m_count ].value  = start;
        m_elements[ m_count ].length = length;
        m_count++;
}

void lua::path::push( const char* p, size_t length )
{
        m_elements[ m_count ].value  = m_path.length();
        m_elements[ m_count ].length = length;
        m_path.append( p, length );
        m_count++;
}

void lua::path::push( const std::string& s, size_t length )
{
        m_elements[ m_count ].value  = m_path.length();
        m_elements[ m_count ].length = length;
        m_path.append( s, 0, length );
        m_count++;
}

bool lua::path::resolve( lua_State* L, bool global /*= true */ ) const
{
        if (m_count == 0) return false;
        if (global) lua_pushglobaltable( L );
        for (int i = 0; i < m_count; ++i )
        {
                if ( lua_istable( L, -1 ) )
                {
                        if ( m_elements[i].length > 0 )
                        {
                                lua_pushlstring( L, m_path.c_str() + m_elements[i].value, m_elements[i].length );
                        }
                        else
                        {
                                lua_pushunsigned( L, m_elements[i].value );
                        }
                        lua_gettable( L, -2 );
                        if (i > 0 || global ) lua_replace( L, -2 );
                }
                else
                {
                        lua_pop(L, 1);
                        return false;
                }
        }
        return true;
}

std::string nv::lua::path::to_string() const
{
        std::string result;
        result.reserve( 2 * m_path.length() );
        bool dot = false;
        for ( const element& e : m_elements )
        {
                if ( dot ) result.append(".");
                if ( e.length == 0 )
                {
                        result.append("[" + nv::to_string( e.value ) + "]" );
                        dot = false;
                }
                else
                {
                        result.append( m_path, e.value, e.length );
                        dot = true;
                }
        }
        return result;
}