local vulkan_sdk_dir = os.getenv("VULKAN_SDK")

local args = {...}
args[1] = args[1] or "basic"
if type(args[1]) ~= "string" or not fs.is_dir("tests/"..args[1]) then args[1] = "basic" end
local output_name = args[1] .. '.exe'

local include_dirs = "-I\"" .. table.concat({
	"include",
	"thirdparty/glfw/include",
	vulkan_sdk_dir .. "/Include",
	vulkan_sdk_dir .. "/Include/vulkan",
	"tests/" .. args[1] .. '/include'
}, "\" -I\"") .. '"'
local src_dirs = {
	"tests/" .. args[1] .. "/src"
}
local obj_dirs = {
	"tests/" .. args[1] .. "/obj"
}
local compiler_flags = table.concat({
	"-c",
	"-g",
	"-O0"
}, ' ')
local library_dirs = '-L\"' .. table.concat({
	"bin/",
	"thirdparty/glfw/bin/src",
	vulkan_sdk_dir .. "/Lib"
}, '\" -L\"') .. '"'
local library_linker_inputs = '-l' .. table.concat({
	"basalt",
	"glfw3",
	"vulkan-1",
	-- Windows
	"msvcrtd",
	"user32",
	"gdi32",
	"shell32"
	-- Linux
}, ' -l')
local linker_flags = table.concat({
	"-g",
	"-O0"
}, ' ')
local shader_src_dir = "bin/shaders/src"
local shader_out_dir = "bin/shaders/out"

if include_dirs == "-I\"\"" then include_dirs = "" end
if library_dirs == "-L\"\"" then library_dirs = "" end
if library_linker_inputs == "-l" then library_linker_inputs = "" end

local cpp_extensions = {
	['.cpp']=true,
	['.hpp']=true
}

local compiler = require("buildscripts.helpers.compiler");

-- NOTE: This is not scalable
--	It does not care what source folder the object comes from
local function srcobj_mapping(src_file, obj_file)
	local base = "./tests/".. args[1]
	-- Return the object file that the source file should be associated with
	if (src_file ~= nil and obj_file == nil) then
		-- Make the source file relative to the test root directory'
		local file = src_file .. '.o'
		return base .. '/obj/' .. fs.relative_to(file, base)
	-- Return the source files associated with an object file
	elseif (src_file == nil and obj_file ~= nil) then
		return {base .. '/' .. obj_file:sub(#base+6, -3)}
	else error("Invalid usage of srcobj mapping function: type(src_file) = " .. type(src_file) .. ", type(obj_file) = " .. type(obj_file)) end
end


-- Get translation units
local source_files = compiler.get_newer_src_files(src_dirs, cpp_extensions, srcobj_mapping)
local translation_units = compiler.generate_translation_units(source_files, srcobj_mapping)

-- Compile the binary
compiler.print_errors(compiler.compile_translation_units("clang++.exe", 4, translation_units, compiler_flags, include_dirs))

-- Link binary
compiler.print_errors(compiler.link_translation_units("clang++.exe", obj_dirs, {['.o']=true}, "-o bin/" .. output_name, library_dirs, library_linker_inputs, linker_flags))

-- Build shaders
local function shader_srcobj_mapping(src_file, obj_file)
	if (src_file ~= nil and obj_file == nil) then
		return fs.dir(src_file):sub(1,-5) .. 'out/' .. fs.file_name(src_file) .. '.spv'
	elseif (src_file == nil and obj_file ~= nil) then
		return { fs.dir(obj_file):sub(1,-5) .. 'src/' .. fs.file_name(obj_file):sub(1,-#".spv"-1) }
		
	else error("Invalid usage of srcobj mapping function for shader compilation") end
end

-- Get source files
local shader_sources = compiler.get_newer_src_files(shader_src_dir, {[".frag"]=true,[".vert"]=true,[".glsl"]=true}, shader_srcobj_mapping)
local shader_translation_units = compiler.generate_translation_units(shader_sources, shader_srcobj_mapping)
compiler.print_errors(compiler.compile_translation_units("glslc", 4, shader_translation_units))