// Copyright 2016 The University of North Carolina at Chapel Hill
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Please send all BUG REPORTS to <pavel@cs.unc.edu>.
// <http://gamma.cs.unc.edu/FasTC/>

#include "gtest/gtest.h"
#include "FasTC/Pixel.h"

TEST(Pixel, DefaultConstructor) {
  FasTC::Pixel p;
  EXPECT_EQ(p.R(), 0);
  EXPECT_EQ(p.G(), 0);
  EXPECT_EQ(p.B(), 0);
  EXPECT_EQ(p.A(), 0);

  uint8 depth[4];
  p.GetBitDepth(depth);

  for(int i = 0; i < 4; i++) {
    EXPECT_EQ(depth[i], 8);
  }
}

TEST(Pixel, FourWideConstructor) {
  FasTC::Pixel p(1, 2, 3, 4);
  EXPECT_EQ(p.R(), 2);
  EXPECT_EQ(p.G(), 3);
  EXPECT_EQ(p.B(), 4);
  EXPECT_EQ(p.A(), 1);

  uint8 depth[4];
  p.GetBitDepth(depth);

  for(int i = 0; i < 4; i++) {
    EXPECT_EQ(depth[i], 8);
  }

  FasTC::Pixel q(0, 6, -2, 5, 4);
  EXPECT_EQ(q.R(), 6);
  EXPECT_EQ(q.G(), -2);
  EXPECT_EQ(q.B(), 5);
  EXPECT_EQ(q.A(), 0);

  q.GetBitDepth(depth);

  for(int i = 0; i < 4; i++) {
    EXPECT_EQ(depth[i], 4);
  }
}

TEST(Pixel, FromBitsAndAssociatedConstructor) {
  const uint8 bits[8] = { 0xA8, 0xB3, 0x7C, 0x21, 0xBD, 0xD4, 0x09, 0x92 };
  FasTC::Pixel ps[2];
  ps[0] = FasTC::Pixel(bits);
  ps[1].FromBits(bits);

  for(int i = 0; i < 2; i++) {
    FasTC::Pixel &p = ps[i];

    EXPECT_EQ(p.A(), 0xA8);
    EXPECT_EQ(p.R(), 0xB3);
    EXPECT_EQ(p.G(), 0x7C);
    EXPECT_EQ(p.B(), 0x21);

    uint8 depth[4];
    p.GetBitDepth(depth);
    for(int j = 0; j < 4; j++) {
      EXPECT_EQ(depth[j], 8);
    }
  }

  const uint8 depth1[4] = { 3, 2, 0, 8 };
  ps[0] = FasTC::Pixel(bits + 3, depth1);
  ps[1].FromBits(bits + 3, depth1);

  for(int i = 0; i < 2; i++) {
    FasTC::Pixel &p = ps[i];

    EXPECT_EQ(p.A(), 0x01);
    EXPECT_EQ(p.R(), 0x00);
    EXPECT_EQ(p.G(), 0xFF);
    EXPECT_EQ(p.B(), 0x37);

    uint8 depth[4];
    p.GetBitDepth(depth);

    EXPECT_EQ(depth[0], 3);
    EXPECT_EQ(depth[1], 2);
    EXPECT_EQ(depth[2], 0);
    EXPECT_EQ(depth[3], 8);
  }


  const uint8 depth2[4] = { 5, 6, 2, 4 };
  ps[0] = FasTC::Pixel(bits + 4, depth2, 2);
  ps[1].FromBits(bits + 4, depth2, 2);

  for(int i = 0; i < 2; i++) {
    FasTC::Pixel &p = ps[i];

    EXPECT_EQ(p.A(), 0x1E);
    EXPECT_EQ(p.R(), 0x3A);
    EXPECT_EQ(p.G(), 0x02);
    EXPECT_EQ(p.B(), 0x00);

    uint8 depth[4];
    p.GetBitDepth(depth);

    EXPECT_EQ(depth[0], 5);
    EXPECT_EQ(depth[1], 6);
    EXPECT_EQ(depth[2], 2);
    EXPECT_EQ(depth[3], 4);
  }
}

TEST(Pixel, ToBits) {
  FasTC::Pixel p;

  uint8 bitDepth[4] = { 2, 8, 1, 7 };
  p.ChangeBitDepth(bitDepth);

  p.A() = 0x2;
  p.R() = 0x56;
  p.G() = 0;
  p.B() = 0x4F;

  uint8 bits[3];
  memset(bits, 0, sizeof(bits));
  p.ToBits(bits, sizeof(bits));

  EXPECT_EQ(bits[0], 0x4F);
  EXPECT_EQ(bits[1], 0x56);
  EXPECT_EQ(bits[2], 0x2);

  memset(bits, 0, sizeof(bits));
  p.ToBits(bits, 3, 2);
  EXPECT_EQ(bits[0], 0x3C);
  EXPECT_EQ(bits[1], 0x59);
  EXPECT_EQ(bits[2], 0x09);
}

TEST(Pixel, ChangeChannelBitDepth) {
  uint8 val = 0x43;
  uint8 depth = 7;

  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 8), 0x87);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 7), 0x43);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 6), 0x22);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 2), 0x2);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 0), 0xFF);

  val = 0x3;
  depth = 3;

  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 8), 0x6D);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 6), 0x1B);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 3), 0x03);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 2), 0x02);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 0), 0xFF);
}

TEST(Pixel, ChangeChannelBitDepthFromZero) {
  uint8 val = 0x43;
  uint8 depth = 0;

  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 8), 0xFF);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 7), 0x7F);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 6), 0x3F);
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 2), 0x03);

  // Shouldn't change it...
  EXPECT_EQ(FasTC::Pixel::ChangeBitDepth(val, depth, 0), 0x43);
}

TEST(Pixel, ChangePixelBitDepth) {
  const uint8 bits[4] = { 0x86, 0xC0, 0x0, 0x0 };
  const uint8 depth[4] = {7, 3, 0, 0};
  FasTC::Pixel p(bits, depth);

  const uint8 newDepth[4] = { 8, 8, 8, 8 };
  p.ChangeBitDepth(newDepth);

  EXPECT_EQ(p.A(), 0x87);
  EXPECT_EQ(p.R(), 0x6D);
  EXPECT_EQ(p.G(), 0xFF);
  EXPECT_EQ(p.B(), 0xFF);

  uint8 outDepth[4];
  p.GetBitDepth(outDepth);

  for(uint32 i = 0; i < 4; i++) {
    EXPECT_EQ(outDepth[i], 8);
  }
}

TEST(Pixel, PackRGBA) {
  const uint8 bits[4] = { 0x86, 0xC0, 0x0, 0x0 };
  const uint8 depth[4] = {7, 3, 0, 0};
  FasTC::Pixel p(bits, depth);

  uint32 val = p.Pack();
  EXPECT_EQ(val, 0x87FFFF6D);
}

TEST(Pixel, UnpackRGBA) {
  uint32 rgba = 0x4619B3FE;
  FasTC::Pixel p;

  p.Unpack(rgba);
  EXPECT_EQ(p.A(), 0x46);
  EXPECT_EQ(p.B(), 0x19);
  EXPECT_EQ(p.G(), 0xB3);
  EXPECT_EQ(p.R(), 0xFE);

  p = FasTC::Pixel(rgba);
  EXPECT_EQ(p.A(), 0x46);
  EXPECT_EQ(p.B(), 0x19);
  EXPECT_EQ(p.G(), 0xB3);
  EXPECT_EQ(p.R(), 0xFE);

  p = FasTC::Pixel();
  uint8 newBitDepth[4] = { 3, 5, 2, 1 };  // A R G B
  p.ChangeBitDepth(newBitDepth);
  p.Unpack(rgba);

  EXPECT_EQ(p.A(), 0x2);
  EXPECT_EQ(p.B(), 0x0);
  EXPECT_EQ(p.G(), 0x3);
  EXPECT_EQ(p.R(), 0x1f);
}

TEST(Pixel, ScaleColor) {
  FasTC::Pixel p;
  uint8 newBitDepth[4] = { 3, 5, 2, 1 };  // A R G B
  p.ChangeBitDepth(newBitDepth);
  
  p.R() = 1;
  p.G() = 2;
  p.B() = 3;
  p.A() = 4;

  FasTC::Pixel sp = p * 3;
  FasTC::Pixel ps = 3 * p;

  EXPECT_EQ(sp.R(), 3); EXPECT_EQ(ps.R(), 3);
  EXPECT_EQ(sp.G(), 6); EXPECT_EQ(ps.G(), 6);
  EXPECT_EQ(sp.B(), 9); EXPECT_EQ(ps.B(), 9);
  EXPECT_EQ(sp.A(), 12); EXPECT_EQ(ps.A(), 12);

  uint8 bd[4];
  sp.GetBitDepth(bd);
  for(uint32 i = 0; i < 4; i++) {
    EXPECT_EQ(bd[i], newBitDepth[i]);
  }

  ps.GetBitDepth(bd);
  for(uint32 i = 0; i < 4; i++) {
    EXPECT_EQ(bd[i], newBitDepth[i]);
  }
}

TEST(Pixel, ByteClamp) {
  FasTC::Pixel p(256, 3, -2, 10);
  p.ClampByte();
  EXPECT_EQ(p.A(), 255);
  EXPECT_EQ(p.R(), 3);
  EXPECT_EQ(p.G(), 0);
  EXPECT_EQ(p.B(), 10);
}


TEST(YCoCgPixel, Conversion) {

  FasTC::Pixel p;
  p.R() = 127;
  p.G() = 127;
  p.B() = 127;
  p.A() = 255;

  FasTC::YCoCgPixel yp (p);
  EXPECT_EQ(yp.Y(), 127);
  EXPECT_EQ(yp.Co(), 128);
  EXPECT_EQ(yp.Cg(), 128);
}

TEST(YCoCgPixel, ConvertBack) {
  FasTC::Pixel p;

  p.R() = 241;
  p.G() = 22;
  p.B() = 102;
  p.A() = 124;

  FasTC::YCoCgPixel yp (p);
  FasTC::Pixel bp = yp.ToRGBA();

  for(int i = 0; i < 4; i++) {
    EXPECT_NEAR(p[i], bp[i], 1);
  }
}