import org.lwjgl.glfw.GLFW.*
import org.lwjgl.glfw.GLFWErrorCallback
import org.lwjgl.opengl.GL
import org.lwjgl.system.MemoryStack
import org.lwjgl.system.MemoryStack.stackPush
import org.lwjgl.glfw.GLFW.glfwPollEvents
import java.awt.SystemColor.window
import org.lwjgl.glfw.GLFW.glfwSwapBuffers
import org.lwjgl.opengl.GL11
import org.lwjgl.opengl.GL11.*
import org.lwjgl.opengl.GL15.*
import org.lwjgl.opengl.GL20
import org.lwjgl.opengl.GL30.*
import kotlin.math.sin
import org.lwjgl.glfw.GLFW.glfwPollEvents
import java.awt.SystemColor.window
import org.lwjgl.glfw.GLFW.glfwSwapBuffers


class App(var width: Int, var height: Int) {
    private val window: Long

    init {
        GLFWErrorCallback.createPrint(System.err).set()
        if (!glfwInit()) throw IllegalStateException("Unable to initialize GLFW")
        glfwWindowHint(GLFW_RESIZABLE, GLFW_TRUE)

        glfwDefaultWindowHints()
        glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3)
        glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2)
        glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE)
        glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GLFW_TRUE)

        window = glfwCreateWindow(width, height, "Amazing test game", 0, 0)
        if (window <= 0) throw IllegalStateException("Unable to create GLFW window")

        glfwSetKeyCallback(window) { window, key, _, action, _ ->
            if (key == GLFW_KEY_ESCAPE && action == GLFW_RELEASE) {
                glfwSetWindowShouldClose(window, true)
            }
        }
        val videoMod = glfwGetVideoMode(glfwGetPrimaryMonitor())!!

        glfwSetWindowPos(window, (videoMod.width() - width) / 2, (videoMod.height() - height) / 2)
        glfwMakeContextCurrent(window)
        glfwSwapInterval(1)
        glfwShowWindow(window)

    }

    fun loop1() {


    }

    fun loop() {
        GL.createCapabilities()
        val vao = glGenVertexArrays()
        stackPush().use {
            val vertices = it.mallocFloat(3 * 6)
            vertices.put(-0.6f).put(-0.4f).put(0f).put(1f).put(0f).put(0f)
            vertices.put(0.6f).put(-0.4f).put(0f).put(0f).put(1f).put(0f)
            vertices.put(0f).put(0.6f).put(0f).put(0f).put(0f).put(1f)
            vertices.flip()
            val vbo = glGenBuffers()

			glBindVertexArray(vao)
            glBindBuffer(GL_ARRAY_BUFFER, vbo)
            glBufferData(GL_ARRAY_BUFFER, vertices, GL_STATIC_DRAW)
        	val floatSize = 4

        	val posAttrib = glGetAttribLocation(shaderProgram, "position")
        	glVertexAttribPointer(posAttrib, 3, GL_FLOAT, false, 6 * floatSize, 0)
        	glEnableVertexAttribArray(posAttrib)

        	val colAttrib = glGetAttribLocation(shaderProgram, "color")
        	glVertexAttribPointer(colAttrib, 3, GL_FLOAT, false, 6 * floatSize, 3L * floatSize)
        	glEnableVertexAttribArray(colAttrib)

        }

        val vertexShader = GL20.glCreateShader(GL20.GL_VERTEX_SHADER)
        GL20.glShaderSource(vertexShader, ClassLoader.getSystemResource("shaders/test.vert").readText())
        GL20.glCompileShader(vertexShader)

        val fragShader = GL20.glCreateShader(GL20.GL_FRAGMENT_SHADER)
        GL20.glShaderSource(fragShader, ClassLoader.getSystemResource("shaders/test.frag").readText())
        GL20.glCompileShader(fragShader)

        val vertStatus = GL20.glGetShaderi(vertexShader, GL20.GL_COMPILE_STATUS)
        if (vertStatus != GL11.GL_TRUE) throw RuntimeException(GL20.glGetProgramInfoLog(vertexShader))

        val fragStatus = GL20.glGetShaderi(fragShader, GL20.GL_COMPILE_STATUS)
        if (fragStatus != GL11.GL_TRUE) throw RuntimeException(GL20.glGetProgramInfoLog(fragShader))
        val shaderProgram = glCreateProgram()
        GL20.glAttachShader(shaderProgram, fragShader)
        GL20.glAttachShader(shaderProgram, vertexShader)
        glBindFragDataLocation(shaderProgram, 0, "fragColor")
        GL20.glLinkProgram(shaderProgram)
        val status = glGetProgrami(shaderProgram, GL_LINK_STATUS)
        if (status != GL_TRUE) {
            throw RuntimeException(glGetProgramInfoLog(shaderProgram))
        }





        while (!glfwWindowShouldClose(window)) {
            glClear(GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT)
            glUseProgram(shaderProgram)
            glBindVertexArray(vao)
            glDrawArrays(GL_TRIANGLES, 0, 3)
            glfwPollEvents()
            glfwSwapBuffers(window)
        }

    }
}