#include "selfdrive/ui/paint.h"

#include <cassert>

#ifdef __APPLE__
#include <OpenGL/gl3.h>
#define NANOVG_GL3_IMPLEMENTATION
#define nvgCreate nvgCreateGL3
#else
#include <GLES3/gl3.h>
#define NANOVG_GLES3_IMPLEMENTATION
#define nvgCreate nvgCreateGLES3
#endif

#define NANOVG_GLES3_IMPLEMENTATION
#include <nanovg_gl.h>
#include <nanovg_gl_utils.h>

#include "selfdrive/hardware/hw.h"

static void draw_chevron(UIState *s, float x, float y, float sz, NVGcolor fillColor, NVGcolor glowColor) {
  // glow
  float g_xo = sz/5;
  float g_yo = sz/10;
  nvgBeginPath(s->vg);
  nvgMoveTo(s->vg, x+(sz*1.35)+g_xo, y+sz+g_yo);
  nvgLineTo(s->vg, x, y-g_xo);
  nvgLineTo(s->vg, x-(sz*1.35)-g_xo, y+sz+g_yo);
  nvgClosePath(s->vg);
  nvgFillColor(s->vg, glowColor);
  nvgFill(s->vg);

  // chevron
  nvgBeginPath(s->vg);
  nvgMoveTo(s->vg, x+(sz*1.25), y+sz);
  nvgLineTo(s->vg, x, y);
  nvgLineTo(s->vg, x-(sz*1.25), y+sz);
  nvgClosePath(s->vg);
  nvgFillColor(s->vg, fillColor);
  nvgFill(s->vg);
}

static void draw_lead(UIState *s, const cereal::RadarState::LeadData::Reader &lead_data, const vertex_data &vd) {
  // Draw lead car indicator
  auto [x, y] = vd;

  float fillAlpha = 0;
  float speedBuff = 10.;
  float leadBuff = 40.;
  float d_rel = lead_data.getDRel();
  float v_rel = lead_data.getVRel();
  if (d_rel < leadBuff) {
    fillAlpha = 255*(1.0-(d_rel/leadBuff));
    if (v_rel < 0) {
      fillAlpha += 255*(-1*(v_rel/speedBuff));
    }
    fillAlpha = (int)(fmin(fillAlpha, 255));
  }

  float sz = std::clamp((25 * 30) / (d_rel / 3 + 30), 15.0f, 30.0f) * 2.35;
  x = std::clamp(x, 0.f, s->fb_w - sz / 2);
  y = std::fmin(s->fb_h - sz * .6, y);
  draw_chevron(s, x, y, sz, nvgRGBA(201, 34, 49, fillAlpha), COLOR_YELLOW);
}

static void ui_draw_line(UIState *s, const line_vertices_data &vd, NVGcolor *color, NVGpaint *paint) {
  if (vd.cnt == 0) return;

  const vertex_data *v = &vd.v[0];
  nvgBeginPath(s->vg);
  nvgMoveTo(s->vg, v[0].x, v[0].y);
  for (int i = 1; i < vd.cnt; i++) {
    nvgLineTo(s->vg, v[i].x, v[i].y);
  }
  nvgClosePath(s->vg);
  if (color) {
    nvgFillColor(s->vg, *color);
  } else if (paint) {
    nvgFillPaint(s->vg, *paint);
  }
  nvgFill(s->vg);
}

static void ui_draw_vision_lane_lines(UIState *s) {
  const UIScene &scene = s->scene;
  NVGpaint track_bg;
  if (!scene.end_to_end) {
    // paint lanelines
    for (int i = 0; i < std::size(scene.lane_line_vertices); i++) {
      NVGcolor color = nvgRGBAf(1.0, 1.0, 1.0, scene.lane_line_probs[i]);
      ui_draw_line(s, scene.lane_line_vertices[i], &color, nullptr);
    }

    // paint road edges
    for (int i = 0; i < std::size(scene.road_edge_vertices); i++) {
      NVGcolor color = nvgRGBAf(1.0, 0.0, 0.0, std::clamp<float>(1.0 - scene.road_edge_stds[i], 0.0, 1.0));
      ui_draw_line(s, scene.road_edge_vertices[i], &color, nullptr);
    }
    track_bg = nvgLinearGradient(s->vg, s->fb_w, s->fb_h, s->fb_w, s->fb_h * .4,
                                          COLOR_WHITE, COLOR_WHITE_ALPHA(0));
  } else {
    track_bg = nvgLinearGradient(s->vg, s->fb_w, s->fb_h, s->fb_w, s->fb_h * .4,
                                          COLOR_RED, COLOR_RED_ALPHA(0));
  }
  // paint path
  ui_draw_line(s, scene.track_vertices, nullptr, &track_bg);
}

// Draw all world space objects.
static void ui_draw_world(UIState *s) {
  nvgScissor(s->vg, 0, 0, s->fb_w, s->fb_h);

  // Draw lane edges and vision/mpc tracks
  ui_draw_vision_lane_lines(s);

  // Draw lead indicators if openpilot is handling longitudinal
  if (s->scene.longitudinal_control) {
    auto lead_one = (*s->sm)["radarState"].getRadarState().getLeadOne();
    auto lead_two = (*s->sm)["radarState"].getRadarState().getLeadTwo();
    if (lead_one.getStatus()) {
      draw_lead(s, lead_one, s->scene.lead_vertices[0]);
    }
    if (lead_two.getStatus() && (std::abs(lead_one.getDRel() - lead_two.getDRel()) > 3.0)) {
      draw_lead(s, lead_two, s->scene.lead_vertices[1]);
    }
  }
  nvgResetScissor(s->vg);
}

static void ui_draw_vision_header(UIState *s) {
  NVGpaint gradient = nvgLinearGradient(s->vg, 0, header_h - (header_h / 2.5), 0, header_h,
                                        nvgRGBAf(0, 0, 0, 0.45), nvgRGBAf(0, 0, 0, 0));
  nvgBeginPath(s->vg);
  nvgRect(s->vg, 0, 0, s->fb_w, header_h);
  nvgFillPaint(s->vg, gradient);
  nvgFill(s->vg);
}

static void ui_draw_vision(UIState *s) {
  const UIScene *scene = &s->scene;
  // Draw augmented elements
  if (scene->world_objects_visible) {
    ui_draw_world(s);
  }
  // TODO: move this to Qt
  ui_draw_vision_header(s);
}

void ui_draw(UIState *s, int w, int h) {
  // Update intrinsics matrix after possible wide camera toggle change
  if (s->fb_w != w || s->fb_h != h) {
    ui_resize(s, w, h);
  }
  glEnable(GL_BLEND);
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  nvgBeginFrame(s->vg, s->fb_w, s->fb_h, 1.0f);
  ui_draw_vision(s);
  nvgEndFrame(s->vg);
  glDisable(GL_BLEND);
}

void ui_nvg_init(UIState *s) {
  // on EON, we enable MSAA
  s->vg = Hardware::EON() ? nvgCreate(0) : nvgCreate(NVG_ANTIALIAS | NVG_STENCIL_STROKES | NVG_DEBUG);
  assert(s->vg);
}

void ui_resize(UIState *s, int width, int height) {
  s->fb_w = width;
  s->fb_h = height;

  auto intrinsic_matrix = s->wide_camera ? ecam_intrinsic_matrix : fcam_intrinsic_matrix;
  float zoom = ZOOM / intrinsic_matrix.v[0];
  if (s->wide_camera) {
    zoom *= 0.5;
  }

  // Apply transformation such that video pixel coordinates match video
  // 1) Put (0, 0) in the middle of the video
  // 2) Apply same scaling as video
  // 3) Put (0, 0) in top left corner of video
  s->car_space_transform.reset();
  s->car_space_transform.translate(width / 2, height / 2 + y_offset)
      .scale(zoom, zoom)
      .translate(-intrinsic_matrix.v[2], -intrinsic_matrix.v[5]);
}