--Create api.md and ReiLua_API.lua files from c sources.

-- Export each module as separate .md file.
local separate = false

if arg ~= nil and arg[1] ~= nil and arg[1] == "-s" then
	separate = true
end

local function split( str, sep )
	if sep == nil then
		sep = "%s"
	end

	local t = {}

	for str in string.gmatch( str, "([^"..sep.."]+)" ) do
		table.insert( t, str )
	end

	return t
end

local function getParamType( param )
	if param == "Color" or param == "Vector2" or param == "Vector3" or param == "Vector4"
	or param == "Quaternion" or param == "Matrix" or param == "Rectangle" then
		return "table"
	elseif param == "float" then
		return "number"
	elseif param == "int" then
		return "integer"
	elseif param == "string" then
		return "string"
	elseif param == "bool" then
		return "boolean"
	else
		return "any"
	end
end

local function parseFunction( line )
	local splitted = split( line, "(" )
	local parString = splitted[2]:sub(2)
	parString = parString:sub( 1, #parString - 2 )
	local parameters = split( parString, "," )
	local str = ""
	local parStr = ""

	for i, par in ipairs( parameters ) do
		local sepPar = split( par, " " )
		parStr = parStr..sepPar[2]
		str = str.."---@param "..sepPar[2].." "
		str = str..getParamType( sepPar[1] ).."\n"

		if i < #parameters then
			parStr = parStr..", "
		end
	end

	local returnsAndFuncName = split( splitted[1], "=" )

	for i, ret in ipairs( split( returnsAndFuncName[1]:sub(3), "," ) ) do
		if ret:sub( 1, 1 ) == " " then
			ret = ret:sub(2)
		end

		str = str.."---@return any "..ret.."\n"
	end

	str = str.."function "..returnsAndFuncName[ #returnsAndFuncName ]:sub(2)

	if parStr ~= "" then
		str = str.."( "..parStr.." )"
	else
		str = str.."()"
	end

	return str.." end\n"
end

local apiFile = io.open( "../API.md", "w" )
local luaApiFile = io.open( "../ReiLua_API.lua", "w" )

-- Header
apiFile:write( "# ReiLua API\n" )

-- Usage.

apiFile:write( "\n## Usage\n" )
apiFile:write( "\nApplication needs 'main.lua' or 'main' file as entry point. ReiLua executable will first look it from same directory. Alternatively, path to the folder where \"main.lua\" is located can be given as argument. There are five Lua functions that the framework will call, 'RL.init', 'RL.process', 'RL.draw', 'RL.log' and 'RL.exit'.\n" )

local FUNC_DESC = {
	init = "This function will be called first when 'main.lua' is found",
	process = "This function will be called every frame during execution. It will get time duration from last frame on argument 'delta'",
	draw = "This function will be called every frame after process and it should have all rendering related functions. Note: Engine will call Raylib functions 'BeginDrawing()' before this function call and 'EndDrawing()' after it. You can still use RL.BeginDrawing() and RL.EndDrawing() manually from anywhere.",
	log = "This function can be used for custom log message handling.",
	exit = "This function will be called on program close. Cleanup could be done here.",
}

apiFile:write( "\n---\n> function RL.init()\n\n"..FUNC_DESC.init.."\n\n---\n" )
apiFile:write( "\n> function RL.process( delta )\n\n"..FUNC_DESC.process.."\n\n---\n" )
apiFile:write( "\n> function RL.draw()\n\n"..FUNC_DESC.draw.."\n\n---\n" )
apiFile:write( "\n> function RL.log( logLevel, message )\n\n"..FUNC_DESC.log.."\n\n---\n" )
apiFile:write( "\n> function RL.exit()\n\n"..FUNC_DESC.exit.."\n\n---\n" )

luaApiFile:write( "-- Put this file into your project folder to provide annotations when using Lua language server.\n\n" )
luaApiFile:write( "RL={}\n\n" )
luaApiFile:write( "-- Functions.\n\n" )

luaApiFile:write(
"---"..FUNC_DESC.init.."\nfunction RL.init() end\n" )
luaApiFile:write(
"---"..FUNC_DESC.process.."\n---@param delta number\nfunction RL.process( delta ) end\n" )
luaApiFile:write(
"---"..FUNC_DESC.draw.."\nfunction RL.draw() end\n" )
luaApiFile:write(
"---"..FUNC_DESC.log.."\n---@param logLevel integer\n---@param message string\nfunction RL.log( logLevel, message ) end\n" )
luaApiFile:write(
"---"..FUNC_DESC.exit.."\nfunction RL.exit() end\n" )

-- Globals.

local srcFile = io.open( "../src/lua_core.c", "r" )
local writing = false

repeat
	line = srcFile:read( "*l" )
	local lineSplit = split( line, " " )

	if line == "/*DOC_END*/" then
		writing = false
		break
	end

	if writing then
		if lineSplit[1] == "\t/*" then
			apiFile:write( "\n## Globals - "..lineSplit[2].."\n" )
			luaApiFile:write( "\n-- Globals - "..lineSplit[2].."\n\n" )
		else
			-- Remove comma from the end.
			local globalName = lineSplit[2]:sub( 1, -2 )

			apiFile:write( "\n"..globalName.."\n" )
			local value = RL[ globalName ]

			globalName = "RL."..globalName

			if value == nil then
				luaApiFile:write( globalName.."=nil\n" )
			elseif type( value ) == "table" then
				-- All tables are colors.
				luaApiFile:write( globalName.."={"
					..math.tointeger( value[1] )..","..math.tointeger( value[2] )..","
					..math.tointeger( value[3] )..","..math.tointeger( value[4] ).."}\n" )
			else
				luaApiFile:write( globalName.."="..value.."\n" )
			end
		end
	end

	if line == "/*DOC_START*/" then
		writing = true
	end
until line == nil

srcFile:close()

-- Types.

apiFile:write( "\n## Types\n\
Raylib structs in Lua\n\n---\n" )

apiFile:write( "\n> Vector2 = { 1.0, 1.0 } or { x = 1.0, y = 1.0 }\n\
Vector2 type\n\n---\n" )
apiFile:write( "\n> Vector3 = { 1.0, 1.0, 1.0 } or { x = 1.0, y = 1.0, z = 1.0 }\n\
Vector3 type\n\n---\n" )
apiFile:write( "\n> Vector4 = { 1.0, 1.0, 1.0, 1.0 } or { x = 1.0, y = 1.0, z = 1.0, w = 1.0 }\n\
Vector4 type\n\n---\n" )
apiFile:write( "\n> Quaternion = { 1.0, 1.0, 1.0, 1.0 } or { x = 1.0, y = 1.0, z = 1.0, w = 1.0 }\n\
Quaternion type\n\n---\n" )
apiFile:write( "\n> Matrix = { { 1.0, 0.0, 0.0, 0.0 }, { 0.0, 1.0, 0.0, 0.0 }, { 0.0, 0.0, 1.0, 0.0 }, { 0.0, 0.0, 0.0, 1.0 } }\n\
OpenGL style 4x4. Identity matrix example\n\n---\n" )
apiFile:write( "\n> Color = { 255, 255, 255, 255 } or { r = 255, g = 255, b = 255, a = 255 }\n\
{ r, g, b ,a }. Color type, RGBA (32bit)\n\n---\n" )
apiFile:write( "\n> Rectangle = { 0.0, 0.0, 1.0, 1.0 } or { x = 0.0, y = 0.0, width = 1.0, height = 1.0 }\n\
{ x, y, width ,height }. Rectangle type\n\n---\n" )
apiFile:write( "\n> Image = ImageId\n\
int id. Image type (multiple pixel formats supported). NOTE: Data stored in CPU memory (RAM)\n\n---\n" )
apiFile:write( "\n> Texture = TextureId\n\
int id. Texture type (multiple internal formats supported). NOTE: Data stored in GPU memory (VRAM)\n\n---\n" )
apiFile:write( "\n> RenderTexture = RenderTextureId\n\
int id. RenderTexture type, for texture rendering\n\n---\n" )
apiFile:write( "\n> Font = FontId\n\
int id. Font type, includes texture and chars data\n\n---\n" )
apiFile:write( "\n> Camera = CameraId\n\
int id. Defines 3d camera position/orientation\n\n---\n" )
apiFile:write( "\n> Mesh = MeshId\n\
int id. Vertex data defining a mesh\n\
```\
mesh{} = {\
  vertices = { Vector3, ... },\
  texcoords = { Vector2, ... },\
  texcoords2 = { Vector2, ... },\
  normals = { Vector3, ... },\
  tangents = { Vector4, ... },\
  colors = { Color, ... },\
  indices = { int, ... },\
}\
```\n\n---\n" )
apiFile:write( "\n> Material = MaterialId\n\
int id. Material type\n\
```\
material{} = {\
  shader = Shader,\
  maps = {\
    {\
      MATERIAL_MAP_ALBEDO,\
      {\
        texture = Texture,\
        color = WHITE,\
        value = 1.0,\
      },\
    },\
    ...\
  },\
  params = { 1.0, 2.0, 3.0, 4.0 },\
}\
```\n\n---\n" )
apiFile:write( "\n> Model = ModelId\n\
int id. Basic 3d Model type\n\n---\n" )
apiFile:write( "\n> Ray = { { 0.0, 0.0, 0.0 }, { 1.0, 0.0, 0.0 } } or { position = { 0.0, 0.0, 0.0 }, direction = { 1.0, 0.0, 0.0 } }\n\
{ position, direction }. Ray type (useful for raycast)\n\n---\n" )
apiFile:write( "\n> RayCollision = { hit = true, distance = 1.0, point = { 0.0, 0.0, 0.0 }, normal = { 0.0, 0.0, 1.0 } }\n\
Raycast hit information. NOTE: Data in named keys\n\n---\n" )
apiFile:write( "\n> BoundingBox = { { 0.0, 0.0, 0.0 }, { 1.0, 1.0, 1.0 } }\n\
{ min, max }. Bounding box type for 3d mesh\n\n---\n" )
apiFile:write( "\n> Sound = SoundId\n\
int id. Basic Sound source and buffer\n\n---\n" )
apiFile:write( "\n> NPatchInfo = { { 0, 0, 24, 24 }, 8, 8, 8, 8, NPATCH_NINE_PATCH } or { source = { 0, 0, 24, 24 }, left = 8, top = 8, right = 8, bottom = 8, layout = NPATCH_NINE_PATCH }\n\
{ Rectangle source, int left, int top, int right, int bottom, int layout }.\
{ Texture source rectangle, Left border offset, Top border offset, Right border offset, Bottom border offset, Layout of the n-patch: 3x3, 1x3 or 3x1 }\n\n---\n" )
apiFile:write( "\n> ModelAnimations = ModelAnimationsId\n\
int id. ModelAnimations\n\n---\n" )

if separate then
	apiFile:close()
end

-- Functions.

local sourceFiles = {
	"core",
	"shapes",
	"textures",
	"text",
	"models",
	"audio",
	"rmath",
	"rgui",
	"lights",
	"rlgl",
	"easings",
}

for _, src in ipairs( sourceFiles ) do
	srcFile = io.open( "../src/"..src..".c", "r" )
	local line = ""
	local funcStr = ""
	local p = false

	if separate then
		apiFile = io.open( src..".md", "w" )
	end

	repeat
		line = srcFile:read( "*l" )

		if line == "*/" then
			p = false
			apiFile:write( "\n---\n" )
			luaApiFile:write( funcStr.."\n" )
			funcStr = ""
		end

		if p then
			apiFile:write( line.."\n" )

			if line:sub( 1, 2 ) == "##" then
				luaApiFile:write( "-- "..line:sub( 4 ).."\n" )
			elseif line:sub( 1, 1 ) == ">" then
				funcStr =  parseFunction( line )
			elseif line:sub( 1, 1 ) ~= "" then
				luaApiFile:write( "---"..line.."\n" )
			end
		end

		if line == "/*" then
			p = true
			apiFile:write( "\n" )
		end
	until line == nil

	srcFile:close()

	if separate then
		apiFile:close()
	end
end

if not separate then
	apiFile:close()
end