/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

#pragma once

#include <cmath>
#include <fabric/graphics/Color.h>
#include <fabric/graphics/Geometry.h>
#include <folly/Optional.h>

namespace facebook {
namespace react {

struct Transform {
  std::array<Float, 16> matrix {{
    1, 0, 0, 0,
    0, 1, 0, 0,
    0, 0, 1, 0,
    0, 0, 0, 1
  }};

  static Transform Identity() {
    return {};
  }

  static Transform Perspective(const Float &perspective) {
    auto transform = Transform {};
    transform.matrix[11] = -1.0 / perspective;
    return transform;
  }

  static Transform Scale(const Float &factorX, const Float &factorY, const Float &factorZ) {
    auto transform = Transform {};
    transform.matrix[0] = factorX;
    transform.matrix[5] = factorY;
    transform.matrix[10] = factorZ;
    return transform;
  }

  static Transform Translate(const Float &x, const Float &y, const Float &z) {
    auto transform = Transform {};
    transform.matrix[12] = x;
    transform.matrix[13] = y;
    transform.matrix[14] = z;
    return transform;
  }

  static Transform Skew(const Float &x, const Float &y) {
    auto transform = Transform {};
    transform.matrix[4] = std::tan(x);
    transform.matrix[1] = std::tan(y);
    return transform;
  }

  static Transform RotateX(const Float &radians) {
    auto transform = Transform {};
    transform.matrix[5] = std::cos(radians);
    transform.matrix[6] = std::sin(radians);
    transform.matrix[9] = -std::sin(radians);
    transform.matrix[10] = std::cos(radians);
    return transform;
  }

  static Transform RotateY(const Float &radians) {
    auto transform = Transform {};
    transform.matrix[0] = std::cos(radians);
    transform.matrix[2] = -std::sin(radians);
    transform.matrix[8] = std::sin(radians);
    transform.matrix[10] = std::cos(radians);
    return transform;
  }

  static Transform RotateZ(const Float &radians) {
    auto transform = Transform {};
    transform.matrix[0] = std::cos(radians);
    transform.matrix[1] = std::sin(radians);
    transform.matrix[4] = -std::sin(radians);
    transform.matrix[5] = std::cos(radians);
    return transform;
  }

  static Transform Rotate(const Float &x, const Float &y, const Float &z) {
    auto transform = Transform {};
    if (x != 0) { transform = transform * Transform::RotateX(x); }
    if (y != 0) { transform = transform * Transform::RotateY(y); }
    if (z != 0) { transform = transform * Transform::RotateZ(z); }
    return transform;
  }

  bool operator ==(const Transform& rhs) const {
    for (auto i = 0; i < 16; i++) {
      if (matrix[i] != rhs.matrix[i]) {
        return false;
      }
    }
    return true;
  }

  bool operator !=(const Transform& rhs) const {
    return !(*this == rhs);
  }

  Transform operator *(const Transform& rhs) const {
    if (*this == Transform::Identity()) {
      return rhs;
    }

    const auto &lhs = *this;
    auto result = Transform {};

    auto lhs00 = lhs.matrix[0], lhs01 = lhs.matrix[1], lhs02 = lhs.matrix[2], lhs03 = lhs.matrix[3],
    lhs10 = lhs.matrix[4], lhs11 = lhs.matrix[5], lhs12 = lhs.matrix[6], lhs13 = lhs.matrix[7],
    lhs20 = lhs.matrix[8], lhs21 = lhs.matrix[9], lhs22 = lhs.matrix[10], lhs23 = lhs.matrix[11],
    lhs30 = lhs.matrix[12], lhs31 = lhs.matrix[13], lhs32 = lhs.matrix[14], lhs33 = lhs.matrix[15];

    auto rhs0 = rhs.matrix[0], rhs1 = rhs.matrix[1], rhs2 = rhs.matrix[2], rhs3 = rhs.matrix[3];
    result.matrix[0] = rhs0 * lhs00 + rhs1 * lhs10 + rhs2 * lhs20 + rhs3 * lhs30;
    result.matrix[1] = rhs0 * lhs01 + rhs1 * lhs11 + rhs2 * lhs21 + rhs3 * lhs31;
    result.matrix[2] = rhs0 * lhs02 + rhs1 * lhs12 + rhs2 * lhs22 + rhs3 * lhs32;
    result.matrix[3] = rhs0 * lhs03 + rhs1 * lhs13 + rhs2 * lhs23 + rhs3 * lhs33;

    rhs0 = rhs.matrix[4]; rhs1 = rhs.matrix[5]; rhs2 = rhs.matrix[6]; rhs3 = rhs.matrix[7];
    result.matrix[4] = rhs0 * lhs00 + rhs1 * lhs10 + rhs2 * lhs20 + rhs3 * lhs30;
    result.matrix[5] = rhs0 * lhs01 + rhs1 * lhs11 + rhs2 * lhs21 + rhs3 * lhs31;
    result.matrix[6] = rhs0 * lhs02 + rhs1 * lhs12 + rhs2 * lhs22 + rhs3 * lhs32;
    result.matrix[7] = rhs0 * lhs03 + rhs1 * lhs13 + rhs2 * lhs23 + rhs3 * lhs33;

    rhs0 = rhs.matrix[8]; rhs1 = rhs.matrix[9]; rhs2 = rhs.matrix[10]; rhs3 = rhs.matrix[11];
    result.matrix[8] = rhs0 * lhs00 + rhs1 * lhs10 + rhs2 * lhs20 + rhs3 * lhs30;
    result.matrix[9] = rhs0 * lhs01 + rhs1 * lhs11 + rhs2 * lhs21 + rhs3 * lhs31;
    result.matrix[10] = rhs0 * lhs02 + rhs1 * lhs12 + rhs2 * lhs22 + rhs3 * lhs32;
    result.matrix[11] = rhs0 * lhs03 + rhs1 * lhs13 + rhs2 * lhs23 + rhs3 * lhs33;

    rhs0 = rhs.matrix[12]; rhs1 = rhs.matrix[13]; rhs2 = rhs.matrix[14]; rhs3 = rhs.matrix[15];
    result.matrix[12] = rhs0 * lhs00 + rhs1 * lhs10 + rhs2 * lhs20 + rhs3 * lhs30;
    result.matrix[13] = rhs0 * lhs01 + rhs1 * lhs11 + rhs2 * lhs21 + rhs3 * lhs31;
    result.matrix[14] = rhs0 * lhs02 + rhs1 * lhs12 + rhs2 * lhs22 + rhs3 * lhs32;
    result.matrix[15] = rhs0 * lhs03 + rhs1 * lhs13 + rhs2 * lhs23 + rhs3 * lhs33;

    return result;
  }
};

enum class PointerEventsMode {
  Auto,
  None,
  BoxNone,
  BoxOnly
};

enum class BorderStyle {
  Solid,
  Dotted,
  Dashed
};

template <typename T>
struct CascadedRectangleEdges {
  using Counterpart = RectangleEdges<T>;
  using OptionalT = folly::Optional<T>;

  OptionalT left {};
  OptionalT top {};
  OptionalT right {};
  OptionalT bottom {};
  OptionalT start {};
  OptionalT end {};
  OptionalT horizontal {};
  OptionalT vertical {};
  OptionalT all {};

  Counterpart resolve(bool isRTL, T defaults) const {
    const auto leading = isRTL ? end : start;
    const auto trailing = isRTL ? start : end;
    const auto horizontalOrAllOrDefault = horizontal.value_or(all.value_or(defaults));
    const auto verticalOrAllOrDefault = vertical.value_or(all.value_or(defaults));

    return Counterpart {
      .left = left.value_or(leading.value_or(horizontalOrAllOrDefault)),
      .right = right.value_or(trailing.value_or(horizontalOrAllOrDefault)),
      .top = top.value_or(verticalOrAllOrDefault),
      .bottom = bottom.value_or(verticalOrAllOrDefault)
    };
  }

  bool operator==(const CascadedRectangleEdges<T> &rhs) const {
    return
      std::tie(this->left, this->top, this->right, this->bottom, this->start, this->end, this->horizontal, this->vertical, this->all) ==
      std::tie(rhs.left, rhs.top, rhs.right, rhs.bottom, rhs.start, rhs.end, rhs.horizontal, rhs.vertical, rhs.all);
  }

  bool operator!=(const CascadedRectangleEdges<T> &rhs) const {
    return !(*this == rhs);
  }
};

template <typename T>
struct CascadedRectangleCorners {
  using Counterpart = RectangleCorners<T>;
  using OptionalT = folly::Optional<T>;

  OptionalT topLeft {};
  OptionalT topRight {};
  OptionalT bottomLeft {};
  OptionalT bottomRight {};
  OptionalT topStart {};
  OptionalT topEnd {};
  OptionalT bottomStart {};
  OptionalT bottomEnd {};
  OptionalT all {};

  Counterpart resolve(bool isRTL, T defaults) const {
    const auto topLeading = isRTL ? topEnd : topStart;
    const auto topTrailing = isRTL ? topStart : topEnd;
    const auto bottomLeading = isRTL ? bottomEnd : bottomStart;
    const auto bottomTrailing = isRTL ? bottomStart : bottomEnd;

    return Counterpart {
      .topLeft = topLeft.value_or(topLeading.value_or(all.value_or(defaults))),
      .topRight = topRight.value_or(topTrailing.value_or(all.value_or(defaults))),
      .bottomLeft = bottomLeft.value_or(topLeading.value_or(all.value_or(defaults))),
      .bottomRight = bottomRight.value_or(topTrailing.value_or(all.value_or(defaults)))
    };
  }

  bool operator==(const CascadedRectangleCorners<T> &rhs) const {
    return
      std::tie(this->topLeft, this->topRight, this->bottomLeft, this->bottomRight, this->topStart, this->topEnd, this->bottomStart, this->bottomEnd, this->all) ==
      std::tie(rhs.topLeft, rhs.topRight, rhs.bottomLeft, rhs.bottomRight, rhs.topStart, rhs.topEnd, rhs.bottomStart, rhs.bottomEnd, rhs.all);
  }

  bool operator!=(const CascadedRectangleCorners<T> &rhs) const {
    return !(*this == rhs);
  }
};

using BorderWidths = RectangleEdges<Float>;
using BorderStyles = RectangleEdges<BorderStyle>;
using BorderColors = RectangleEdges<SharedColor>;
using BorderRadii = RectangleCorners<Float>;

using CascadedBorderWidths = CascadedRectangleEdges<Float>;
using CascadedBorderStyles = CascadedRectangleEdges<BorderStyle>;
using CascadedBorderColors = CascadedRectangleEdges<SharedColor>;
using CascadedBorderRadii = CascadedRectangleCorners<Float>;

struct BorderMetrics {
  BorderColors borderColors {};
  BorderWidths borderWidths {};
  BorderRadii borderRadii {};
  BorderStyles borderStyles {};

  bool operator==(const BorderMetrics &rhs) const {
    return
      std::tie(this->borderColors, this->borderWidths, this->borderRadii, this->borderStyles) ==
      std::tie(rhs.borderColors, rhs.borderWidths, rhs.borderRadii, rhs.borderStyles);
  }

  bool operator!=(const BorderMetrics &rhs) const {
    return !(*this == rhs);
  }
};

} // namespace react
} // namespace facebook