#include "canvas/BackGround.hpp"
#include "Math.hpp"

#include "raylib.h"
#include "rlgl.h"
#include "raymath.h"
#include "external/stb_perlin.h"

// Public
void BackGround::init(int size)
{
  this->size = size;
}

void BackGround::newGen()
{
  ClearBackground(backGroundColor);
  starts();
  moon();
  mounten(20, 0.3, (int)(mounten1 * size), (int)(mounten2 * size), backMountenColor);
  mounten(21, 0.3, (int)(mounten2 * size), (int)(mounten3 * size), ColorLerp(backMountenColor, frontMountenColor, colorRatio1));
  mounten(23, 0.3, (int)(mounten3 * size), (int)(mounten4 * size), ColorLerp(backMountenColor, frontMountenColor, colorRatio2));
}

void BackGround::starts()
{
  rlSetTexture(texShapes.id);
  rlBegin(RL_TRIANGLES);
  rlNormal3f(0.0f, 0.0f, 1.0f);

  bool star = true;

  for (size_t i = 1; i <= numOfStarts; i++)
  {
    int x = GetRandomValue(0, size);
    int y = GetRandomValue(0, size);
    int weight = GetRandomValue(1, 3);

    float alph = ((float)GetRandomValue(10, 200)) / 255.0f;
    Color color = ColorLerp(backGroundColor, starColor, alph);

    rlColor4ub(color.r, color.g, color.b, color.a);
    if (star)
    {
      // topLeft
      rlVertex2f(x, y);
      // bottomLeft
      rlVertex2f(x, y + weight);
      // topRight
      rlVertex2f(x + weight, y);
    }
    else
    {
      // bottomRight
      rlVertex2f(x + weight, y + weight);
      // topRight
      rlVertex2f(x + weight, y);
      // bottomLeft
      rlVertex2f(x, y + weight);
    }
    star = !star;
  }
  rlEnd();
  rlSetTexture(0);
}

void BackGround::moon()
{
  int xpos = GetRandomValue(100, size - 100);
  int ypos = GetRandomValue(100, (int)(maxYPosOfMoon * size));
  int r = GetRandomValue((int)(minSizeOfMoon * size), (int)(maxSizeOfMoon * size));
  int ring1 = (float)r * bigRingRatio;
  int ring2 = (float)r * smallRingRatio;

  DrawCircle(xpos, ypos, r + ring1, ColorLerp(backGroundColor, moonColor, bigRingBlend));
  DrawCircle(xpos, ypos, r + ring2, ColorLerp(backGroundColor, moonColor, smallRingBlend));
  DrawCircle(xpos, ypos, r, moonColor);
}

void BackGround::mounten(size_t mountenSegments, float scale, int min, int max, Color color)
{
  // get random offset in the perlin noise
  int offsetX = GetRandomValue(20, 1000);
  int offsetY = GetRandomValue(20, 1000);

  int x = 0;
  int diff = size / (mountenSegments - 1);

  float nx = (float)offsetX * scale;
  float p = stb_perlin_fbm_noise3(nx, offsetY, 1.0f, 2.0f, 0.5f, 6);
  p = (p + 1.0f) / 2.0f;
  int y = Lerp(min, max, p);

  rlSetTexture(texShapes.id);
  rlBegin(RL_TRIANGLES);
  rlNormal3f(0.0f, 0.0f, 1.0f);
  rlColor4ub(color.r, color.g, color.b, color.a);

  for (size_t i = 1; i <= mountenSegments; i++)
  {
    // topLeft
    rlVertex2f(x, y);
    // bottomLeft
    rlVertex2f(x, size);

    nx = (float)(i + offsetX) * scale;
    p = stb_perlin_fbm_noise3(nx, offsetY, 1.0f, 2.0f, 0.5f, 6);
    p = (p + 1.0f) / 2.0f;
    y = Lerp(min, max, p);
    x += diff;
    // topRight
    rlVertex2f(x, y);

    // bottomRight
    rlVertex2f(x, size);
    // topRight
    rlVertex2f(x, y);

    rlVertex2f(x - diff, size);
  }
  rlEnd();
  rlSetTexture(0);
}