--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"
	elseif param == "bool" then return "boolean"
	elseif param:sub( #param - 1, #param ) == "{}" then return "table"
	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## Functions\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.event', '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.",
	event = "This function will be called on events input. Content of event table is determined by event type.",
	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.event( event )\n\n"..FUNC_DESC.event.."\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.event.."\n---@param event table\nfunction RL.event( event ) 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" )
luaApiFile:write(
"---"..FUNC_DESC.exit.."\nfunction RL.exit() end\n" )

-- Object unloading.

apiFile:write( "\n## Object unloading\n" )
apiFile:write( "\nSome objects allocate memory that needs to be freed when object is no longer needed. By default objects like Textures are unloaded by the Lua garbage collector. It is generatty however recommended to handle this manually in more complex projects. You can change the behavior with SetGCUnload.\n" )

-- Arguments.

apiFile:write( "\n## Arguments\n" )
apiFile:write( "\nArguments are stored in 'RL.arg' array.\n" )

-- 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, 2 components\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, 3 components\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, 4 components\n\n---\n" )
apiFile:write( "\n> Quaternion = { 0.0, 0.0, 0.0, 1.0 } or { x = 0.0, y = 0.0, z = 0.0, w = 1.0 }\n\
Quaternion, 4 components (Vector4 alias)\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\
Matrix, 4x4 components, column major, OpenGL style, right-handed. Identity matrix example\n\n---\n" )
apiFile:write( "\n> Color = { 255, 255, 255, 255 } or { r = 255, g = 255, b = 255, a = 255 }\n\
Color, 4 components, R8G8B8A8 (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\
Rectangle, 4 components\n\n---\n" )
apiFile:write( "\n> Image = Userdata\n\
Image, pixel data stored in CPU memory (RAM)\n\n---\n" )
apiFile:write( "\n> Texture = Userdata\n\
Texture, tex data stored in GPU memory (VRAM)\
```\
textureData = {\
	id = unsigned int,		--OpenGL texture id\
	width = int,			--Texture base width\
	height = int,			--Texture base height\
	mipmaps = int,			--Mipmap levels, 1 by default\
	format = int			--Data format (PixelFormat type)\
}\
```\n\n---\n" )
apiFile:write( "\n> RenderTexture = Userdata\n\
RenderTexture, fbo for texture rendering\
```\
renderTextureData = {\
	id = unsigned int,		--OpenGL texture id\
	texture = Texture,		--Texture base width\
	depth = Texture,		--Texture base height\
}\
```\n\n---\n" )
apiFile:write( "\n> Font = Userdata\n\
Font, font texture and GlyphInfo array data\n\n---\n" )
apiFile:write( "\n> Camera2D = Userdata\n\
Camera2D, defines position/orientation in 2d space\n\n---\n" )
apiFile:write( "\n> Camera3D = Userdata\n\
Camera, defines position/orientation in 3d space\n\n---\n" )
apiFile:write( "\n> Mesh = Userdata\n\
Mesh, vertex data and vao/vbo\n\
```\
meshData = {\
	vertices = Vector3{},		--Vertex position (XYZ - 3 components per vertex) (shader-location = 0)\
	texcoords = Vector2{},		--Vertex texture coordinates (UV - 2 components per vertex) (shader-location = 1)\
	texcoords2 = Vector2{},		--Vertex texture second coordinates (UV - 2 components per vertex) (shader-location = 5)\
	normals = Vector3{},		--Vertex normals (XYZ - 3 components per vertex) (shader-location = 2)\
	tangents = Vector4{},		--Vertex tangents (XYZW - 4 components per vertex) (shader-location = 4)\
	colors = Color{},			--Vertex colors (RGBA - 4 components per vertex) (shader-location = 3)\
	indices = int{}				--Vertex indices (in case vertex data comes indexed)\
}\
```\n\n---\n" )
apiFile:write( "\n> Material = Userdata\n\
Material, includes shader and maps\n\
```\
materialData = {\
	shader = Shader,\
	maps = {									--Material maps array (MAX_MATERIAL_MAPS)\
		{\
    		MATERIAL_MAP_*,						--Example MATERIAL_MAP_ALBEDO\
			{\
    			texture = Texture,				--Material map texture\
        		color = Color,					--Material map color\
        		value = float,					--Material map value\
      		},\
    	},\
    	...\
  	},\
  	params = { float, float, float, float }		--Material generic parameters (if required)\
}\
```\n\n---\n" )
apiFile:write( "\n> Model = Userdata\n\
Model, meshes, materials and animation data\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\
Ray, ray for raycasting\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\
RayCollision, ray hit information\n\n---\n" )
apiFile:write( "\n> BoundingBox = { { 0.0, 0.0, 0.0 }, { 1.0, 1.0, 1.0 } } or { min = { 0.0, 0.0, 0.0 }, max = { 1.0, 1.0, 1.0 } }\n\
BoundingBox\n\n---\n" )
apiFile:write( "\n> GlyphInfo = { value = int, offsetX = int, offsetY = int, advanceX = int, image = Image }\n\
GlyphInfo, font characters glyphs info\n\n---\n" )
apiFile:write( "\n> Wave = Userdata\n\
Wave, audio wave data\n\n---\n" )
apiFile:write( "\n> Sound = Userdata\n\
Sound\n\n---\n" )
apiFile:write( "\n> Music = Userdata\n\
Music, audio stream, anything longer than ~10 seconds should be streamed\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\
NPatchInfo, n-patch layout info\n\n---\n" )
apiFile:write( "\n> ModelAnimations = Userdata\n\
ModelAnimation\n\n---\n" )
apiFile:write( "\n> Buffer = Buffer userdata\n\
Data buffer for C primitive types. Type should be one of the Buffer types.\n\n---\n" )

-- Events.

apiFile:write( "\n## Events\n" )
apiFile:write( "\nContent of event table received by RL.event.\n" )
apiFile:write( "\n### Window events\n" )
apiFile:write( "\n---\n> { type: RL.EVENT_WINDOW_SIZE, int width, int height }\n\n WindowSize Callback, runs when window is resized.\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_WINDOW_MAXIMIZE, int maximized }\n\n Window Maximize Callback, runs when window is maximized.\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_WINDOW_ICONYFY, int iconified }\n\n WindowIconify Callback, runs when window is minimized/restored.\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_WINDOW_FOCUS, int focused }\n\n WindowFocus Callback, runs when window get/lose focus.\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_WINDOW_DROP, int count, string{} paths }\n\n Window Drop Callback, runs when drop files into window.\n\n---\n" )
apiFile:write( "\n### Input events\n" )
apiFile:write( "\n---\n> { type: RL.EVENT_KEY, int key, int scancode, int action, int mods }\n\n Keyboard Callback, runs on key pressed.\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_CHAR, int key }\n\n Char Key Callback, runs on key pressed (get char value).\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_MOUSE_BUTTON, int button, int action, int mods }\n\n Mouse Button Callback, runs on mouse button pressed.\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_MOUSE_CURSOR_POS, number x, number y }\n\n Cursor Position Callback, runs on mouse move.\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_MOUSE_SCROLL, number xoffset, number yoffset }\n\n Srolling Callback, runs on mouse wheel.\n\n---\n" )
apiFile:write( "\n> { type RL.EVENT_CURSOR_ENTER, int enter }\n\n Cursor Enter Callback, cursor enters client area.\n\n---\n" )

if separate then
	apiFile:close()
end

-- Globals.

local srcFile = io.open( "../src/lua_core.c", "r" )
local writing = false
local globalVariableCount = 0

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 )
			local value = RL[ globalName ]
			local comment = lineSplit[6] -- First split after //

			if comment ~= nil then
				local i = 7

				while lineSplit[i] ~= nil do
					comment = comment.." "..lineSplit[i]
					i = i + 1
				end
				luaApiFile:write( "---"..comment.."\n" )
			end
			
			globalVariableCount = globalVariableCount + 1

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

			if comment ~= nil then
				apiFile:write( comment.."\n\n" )
			end

			apiFile:write( "---\n\n" )
		end
	end

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

srcFile:close()

-- Functions.

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

local functionCount = 0

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 )
				functionCount = functionCount + 1
			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

print( "Parsed:\n"..globalVariableCount.." Global variables\n"..functionCount.." Functions" )