// Copyright (C) 2012-2015 ChaosForge Ltd
// http://chaosforge.org/
//
// This file is part of Nova libraries. 
// For conditions of distribution and use, see copying.txt file in root folder.

#include "nv/lua/lua_path.hh"

#include "nv/lua/lua_raw.hh"

using namespace nv;

void lua::path::parse()
{
	if ( m_elements[0].length == 0 || m_elements[0].str == nullptr ) return;
	string_view spath( m_elements[0].str, m_elements[0].length );
	m_count = 0;
	size_t point = spath.find( '.' );

	while ( point != string_view::npos )
	{
		m_elements[m_count].str    = spath.data();
		m_elements[m_count].length = point;
		m_count++;
		spath.remove_prefix( point + 1 );
		point = spath.find( '.' );
	}

	m_elements[m_count].str    = spath.data();
	m_elements[m_count].length = spath.length();
	m_count++;
}

void lua::path::push( nv::uint32 value )
{
	m_elements[ m_count ].value  = value;
	m_elements[ m_count ].length = 0;
	m_count++;
}

void nv::lua::path::push( string_view p )
{
	m_elements[ m_count ].str    = p.data();
	m_elements[ m_count ].length = p.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 ( uint32 i = 0; i < m_count; ++i )
	{
		if ( lua_istable( L, -1 ) )
		{
			if ( m_elements[i].length > 0 )
			{
				lua_pushlstring( L, m_elements[i].str, 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
{
	char buffer[64];
	char* start   = buffer;
	char* current = buffer;
	bool dot = false;
	bool oos = false;
	for ( const element& e : m_elements )
	{
		if ( current - start > 48 ) { oos = true; break; }
		if ( dot ) *current++ = '.';
		if ( e.length == 0 )
		{
			*current++ = '[';
			current += uint32_to_buffer( e.value, current );
			*current++ = ']';
			dot = false;
		}
		else
		{
			if ( size_t(current - start) + e.length > 60 ) { oos = true; break; }
			nvmemcpy( current, e.str, e.length );
			current += e.length;
			dot = true;
		}
	}
	if (oos) 
	{ 
		*current++ = '.';
		*current++ = '.';
		*current++ = '.';
	}
	*current++ = '\0';
	return std::string( buffer, size_t(current - start - 1) );
}