// Copyright (C) 2012-2013 ChaosForge / Kornel Kisielewicz
// 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( uint32 e )
{
	m_elements[ m_count ].value  = e;
	m_elements[ m_count ].length = 0;
	m_count++;
}

void lua::path::push( uint32 start, uint32 length )
{
	m_elements[ m_count ].value  = start;
	m_elements[ m_count ].length = length;
	m_count++;
}

void lua::path::push( const char* p, uint32 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, uint32 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;
}