#include "funcs.h"

extern float deltaTime;
extern float lastX, lastY;
extern const float mouseSensitivity = 0.08f;
extern float zoom;

glm::vec3 camPos = glm::vec3(0.0f, 0.0f, 3.0f);
glm::vec3 camDir = glm::vec3(0.0f, 0.0f, -1.0f);
glm::vec3 camUp = glm::vec3(0.0f, 1.0f, 0.0f);
float yaw=-90.0f, pitch=0.0f, roll=0.0f;
bool firstMouse = true;

void framebuffer_size_callback(GLFWwindow* window, int width, int height) {
    glViewport(0, 0, width, height);
}

void mouse_callback(GLFWwindow*, double xpos, double ypos) {
    if (firstMouse) {
        lastX = xpos;
        lastY = ypos;
        firstMouse = false;
    }

    float xOffset = xpos - lastX;
    float yOffset = lastY - ypos;
    lastX = xpos;
    lastY = ypos;
    xOffset *= mouseSensitivity;
    yOffset *= mouseSensitivity;

    yaw += xOffset;
    pitch += yOffset;
    pitch = (pitch > 89.0f)?89.0f: ((pitch < -89.0f)?-89.0f:pitch );
    camDir.x = cos(glm::radians(yaw)) * cos(glm::radians(pitch));
    camDir.y = sin(glm::radians(pitch));
    camDir.z = sin(glm::radians(yaw)) * cos(glm::radians(pitch));
    camDir = glm::normalize(camDir);
}

void scroll_callback(GLFWwindow*, double xOffset, double yOffset) {
    zoom -= (float)yOffset;
    if (zoom < 1.0f) {
        zoom = 1.0f;
    } else if ( zoom > 45.0f) {
        zoom = 45.0f;
    }
}

void processInput(GLFWwindow* window) {
    float camSpeed = 3.5f * deltaTime;
    if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS) {
        glfwSetWindowShouldClose(window, true);
    }
    if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS) {
        camPos += camSpeed * camDir;
    }
    if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS) {
        camPos -= camSpeed * camDir;
    }
    if (glfwGetKey(window, GLFW_KEY_A) == GLFW_PRESS) {
        camPos -= camSpeed * glm::cross(camDir, camUp);
    }
    if (glfwGetKey(window, GLFW_KEY_D) == GLFW_PRESS) {
        camPos += camSpeed * glm::cross(camDir, camUp);
    }
    if (glfwGetKey(window, GLFW_KEY_SPACE) == GLFW_PRESS) {
        camPos += camSpeed * camUp;
    }
    if (glfwGetKey(window, GLFW_KEY_LEFT_SHIFT) == GLFW_PRESS) {
        camPos -= camSpeed * camUp;
    }
}