#include <raylib.h>
#include <raymath.h>
#include <cmath>
#include <vector>

Vector2 newPoint(Vector2 start, float len, float angleD){
  float angleR = (angleD * PI) / 180; // radian
  return {start.x + len * cos(angleR), start.y - len * sin(angleR)};
}

void drawBranch(Vector2 startV, Vector2 endV, Color startC, Color endC, int startR, int endR){
  float fstep = 0.05;
  for (float i = 0; i < 1.05; i += fstep)
  {
    Vector2 point = Vector2Lerp(startV, endV, i);
    Color color = ColorLerp(startC, endC, i);
    int size = Lerp(startR, endR, i);
    DrawCircleV(point, size, color);
  }
}

constexpr float screenWidth = 800;
constexpr float screenHeight = 800;

constexpr float len = 300;
constexpr float angleD = 100;
constexpr Vector2 start = {screenWidth / 2, screenHeight - 100};
constexpr float radius = 20;
constexpr float radiusS = 80;
constexpr float radiusE = 60;
constexpr Color colorS = RED;
constexpr Color colorE = GREEN;

typedef void (*slika)();

int idx = 0;

std::vector<slika> v_slik = {
    []()
    {
      DrawCircleV(start, radius, BLACK);
    },

    []()
    {
      Vector2 end = {start.x, start.y - len};
      DrawCircleV(start, radius, BLACK);
      DrawLineEx(start, end, 10, BLACK);
    },

    []()
    {
      Vector2 end = newPoint(start, len, angleD);
      DrawCircleV(start, radius, BLACK);
      DrawLineEx(start, end, 10, BLACK);
      DrawCircleV(end, radius, BLACK);
      DrawCircleSectorLines(start, len / 3, 360 - angleD, 360, 30, BLACK);
    },

    []()
    {
      Vector2 end = newPoint(start, len, angleD);
      DrawCircleV(start, radius, BLACK);
      DrawLineEx(start, end, 10, BLACK);
      DrawCircleV(end, radius, BLACK);
      DrawCircleLinesV(start, radiusS, BLACK);
      DrawCircleLinesV(end, radiusE, BLACK);
    },

    []()
    {
      Vector2 end = newPoint(start, len, angleD);
      DrawLineEx(start, end, 10, BLACK);
      DrawCircleV(start, radiusS, colorS);
      DrawCircleV(end, radiusE, colorE);
    },

    []()
    {
      Vector2 end = newPoint(start, len, angleD);
      drawBranch(start, end, colorS, colorE, radiusS, radiusE);
    },

    []()
    {
      Vector2 p = newPoint(start, len, angleD);
      drawBranch(start, p, colorS, colorE, radiusS, radiusE);
      Vector2 p1 = newPoint(p, len, 135);
      Vector2 p2 = newPoint(p, len, 90);
      Vector2 p3 = newPoint(p, len, 45);
      DrawLineEx(p, p1, 10, BLACK);
      DrawLineEx(p, p2, 10, BLACK);
      DrawLineEx(p, p3, 10, BLACK);
      DrawCircleV(p, radius, BLACK);
      DrawCircleV(p1, radius, BLACK);
      DrawCircleV(p2, radius, BLACK);
      DrawCircleV(p3, radius, BLACK);
    },

    []()
    {
      Vector2 p = newPoint(start, len, angleD);
      drawBranch(start, p, colorS, colorE, radiusS, radiusE);
      Vector2 p1 = newPoint(p, len, 135);
      Vector2 p2 = newPoint(p, len, 90);
      Vector2 p3 = newPoint(p, len, 45);
      drawBranch(p, p1, colorE, BLUE, radiusE, 50);
      drawBranch(p, p2, colorE, ORANGE, radiusE, 50);
      drawBranch(p, p3, colorE, PURPLE, radiusE, 50);
    },

  };

int main(int argc, char *argv[])
{
  InitWindow(screenWidth, screenHeight, "Slike");
  SetTargetFPS(60);

  while (!WindowShouldClose())
  {
    BeginDrawing();
    if (IsKeyPressed(KEY_S))
    {
      TakeScreenshot(TextFormat("slika%.2d.png", idx));
    }
    if (IsKeyPressed(KEY_N))
    {
      idx++;
      if (idx >= v_slik.size())
        idx = v_slik.size() - 1;
    }
    if (IsKeyPressed(KEY_P))
    {
      idx--;
      if (idx < 0)
        idx = 0;
    }
    ClearBackground(WHITE);
    v_slik[idx]();
  
    EndDrawing();
  }


  CloseWindow();
  return 0;
}