-- Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>

--

-- This software is provided 'as-is', without any express or implied

-- warranty. In no event will the authors be held liable for any damages

-- arising from the use of this software.

--

-- Permission is granted to anyone to use this software for any purpose,

-- including commercial applications, and to alter it and redistribute it

-- freely.

--

-- Meta-build system using premake created and maintained by

-- Benjamin Henning <b.henning@digipen.edu>

-- This is kept just for windows because the other platforms use different means

-- for determining dependence or compatibility.

--[[

sdl_depends.lua

This file simply contains a function for determining whether a dependency

exists on the Windows platform, given a possible environmental variable,

delimited search paths, and a main and/or sub-directory paths for more

elaborate pattern matching.

]]

-- find_dependency_dir_windows(env, main_search_path, main_dir_path)

-- Attempt to resolve a dependency (true or false) folder based on either an

-- environmental variable, start search path, or both. If both are present,

-- the environmental variable will be preferred. If neither are present, this

-- function returns false.

--

-- Arguments:

-- env The name of the environmental variable to treat as a path

-- main_search_paths Paths to look for the main directory in

-- main_dir_path The a path that must be contained between main_search_path and sub_dir_path

-- sub_dir_path The path of the directories that should exist at the searched path

function find_dependency_dir_windows(env, main_search_paths, main_dir_path, sub_dir_path)

if not os.is("windows") then -- if not windows, then fail

return false

end

if env == nil and (main_search_paths == nil or #main_search_paths == 0) then

return false

end

local env_path = nil

local main_path = nil

if env ~= nil then env_path = os.getenv(env) end

local search_table = { n = 0 }

if main_search_paths ~= nil then

for k,main_search_path in ipairs(explode(main_search_paths, ";")) do

local directories = os.matchdirs(main_search_path .. "/**" .. main_dir_path .. "*")

for k,v in pairs(directories) do

table.insert(search_table, v)

end

end

end

if env_path ~= nil then table.insert(search_table, env_path) end

local search_path = table.concat(search_table, ";")

local result_path = os.dirpathsearch(sub_dir_path, search_path, ";")

if result_path == nil then

return false

end

local found_dir = os.isdir(result_path)

local abs_path = path.getabsolute(result_path)

if found_dir and env_path ~= nil then

abs_path = abs_path:gsub("\\", "/")

env_path = env_path:gsub("\\", "/")

local pos = abs_path:indexOf(env_path)

if pos ~= nil then

abs_path = abs_path:sub(1, pos - 1) .. "$(" .. env .. ")/" .. abs_path:sub(pos + #env_path)

end

end

-- we want the path in terms of '/'

return found_dir, abs_path

end