module main

import gg
import time
import math

const size = 700
const scale = 50.0

struct Context {
mut:
    gg &gg.Context = unsafe { nil }
}

fn main() {
    mut context := &Context{}
    context.gg = gg.new_context(
        width:         size
        height:        size
        font_size:     20
        user_data:     context
        window_title:  'Graph builder'
        create_window: true
        frame_fn:      frame
        resizable:     true
        bg_color:      gg.white
    )
    context.gg.run()
}

fn frame(mut ctx Context) {
    ctx.gg.begin()
    ctx.draw()
    ctx.gg.end()
}

@[live]
fn (ctx &Context) draw() {
    s := gg.window_size()
    mut w := s.width
    mut h := s.height
    if gg.high_dpi() {
        w /= 2
        h /= 2
    }
    ctx.gg.draw_line(0, h / 2, w, h / 2, gg.gray) // x axis
    ctx.gg.draw_line(w / 2, 0, w / 2, h, gg.gray) // y axis
    atime := f64(time.ticks() / 10)
    stime := math.sin(2.0 * math.pi * f64(time.ticks() % 6000) / 6000)
    mut y := 0.0
    blue := gg.Color{
        r: 100
        g: 100
        b: 200
    }
    red := gg.Color{
        r: 200
        g: 100
        b: 100
    }
    y = 1.0
    max := f32(w) / (2 * scale)
    min := -max
    for x := min; x <= max; x += 0.01 {
        // y = x*x + 2
        // y = x * x + stime * stime
        // y = stime
        // y = stime * h
        y = stime * 1.0 * math.sin(x + stime + atime / 32) * ((h / 256) + x)
        // y = (stime * x) * x + stime
        // y = (x + 3) * (x + 3) / stime + stime*2.5
        // y = math.sqrt(30.0 - x * x) * stime
        // y -= (stime-0.5) + stime
        // ctx.gg.draw_rect_filled(f32((w/2) + x * scale), f32((h/2) - y * scale), 2, 2, blue)
        ctx.gg.draw_rect_filled(f32((w / 2) + x * scale), f32((h / 2) - y * scale), 2,
            (f32(y) * scale), blue)
        ctx.gg.draw_rect_filled(f32((w / 2) + x * scale), f32((h / 2) + y * scale), 2,

            (f32(y) * scale) + 32, red)
    }
}