/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * 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.
 */

#define LOG_TAG "hwc-platform"

#include "drmresources.h"
#include "platform.h"

#include <cutils/log.h>

namespace android {

std::vector<DrmPlane *> Planner::GetUsablePlanes(
    DrmCrtc *crtc, std::vector<DrmPlane *> *primary_planes,
    std::vector<DrmPlane *> *overlay_planes) {
  std::vector<DrmPlane *> usable_planes;
  std::copy_if(primary_planes->begin(), primary_planes->end(),
               std::back_inserter(usable_planes),
               [=](DrmPlane *plane) { return plane->GetCrtcSupported(*crtc); });
  std::copy_if(overlay_planes->begin(), overlay_planes->end(),
               std::back_inserter(usable_planes),
               [=](DrmPlane *plane) { return plane->GetCrtcSupported(*crtc); });
  return usable_planes;
}

std::tuple<int, std::vector<DrmCompositionPlane>> Planner::ProvisionPlanes(
    std::map<size_t, DrmHwcLayer *> &layers, bool use_squash_fb, DrmCrtc *crtc,
    std::vector<DrmPlane *> *primary_planes,
    std::vector<DrmPlane *> *overlay_planes) {
  std::vector<DrmCompositionPlane> composition;
  std::vector<DrmPlane *> planes =
      GetUsablePlanes(crtc, primary_planes, overlay_planes);
  if (planes.empty()) {
    ALOGE("Display %d has no usable planes", crtc->display());
    return std::make_tuple(-ENODEV, std::vector<DrmCompositionPlane>());
  }

  // If needed, reserve the squash plane at the highest z-order
  DrmPlane *squash_plane = NULL;
  if (use_squash_fb) {
    if (!planes.empty()) {
      squash_plane = planes.back();
      planes.pop_back();
    } else {
      ALOGI("Not enough planes to reserve for squash fb");
    }
  }

  // If needed, reserve the precomp plane at the next highest z-order
  DrmPlane *precomp_plane = NULL;
  if (layers.size() > planes.size()) {
    if (!planes.empty()) {
      precomp_plane = planes.back();
      planes.pop_back();
      composition.emplace_back(DrmCompositionPlane::Type::kPrecomp,
                               precomp_plane, crtc);
    } else {
      ALOGE("Not enough planes to reserve for precomp fb");
    }
  }

  // Go through the provisioning stages and provision planes
  for (auto &i : stages_) {
    int ret = i->ProvisionPlanes(&composition, layers, crtc, &planes);
    if (ret) {
      ALOGE("Failed provision stage with ret %d", ret);
      return std::make_tuple(ret, std::vector<DrmCompositionPlane>());
    }
  }

  if (squash_plane)
    composition.emplace_back(DrmCompositionPlane::Type::kSquash, squash_plane,
                             crtc);

  return std::make_tuple(0, std::move(composition));
}

int PlanStageProtected::ProvisionPlanes(
    std::vector<DrmCompositionPlane> *composition,
    std::map<size_t, DrmHwcLayer *> &layers, DrmCrtc *crtc,
    std::vector<DrmPlane *> *planes) {
  int ret;
  int protected_zorder = -1;
  for (auto i = layers.begin(); i != layers.end();) {
    if (!i->second->protected_usage()) {
      ++i;
      continue;
    }

    ret = Emplace(composition, planes, DrmCompositionPlane::Type::kLayer, crtc,
                  i->first);
    if (ret)
      ALOGE("Failed to dedicate protected layer! Dropping it.");

    protected_zorder = i->first;
    i = layers.erase(i);
  }

  if (protected_zorder == -1)
    return 0;

  // Add any layers below the protected content to the precomposition since we
  // need to punch a hole through them.
  for (auto i = layers.begin(); i != layers.end();) {
    // Skip layers above the z-order of the protected content
    if (i->first > static_cast<size_t>(protected_zorder)) {
      ++i;
      continue;
    }

    // If there's no precomp layer already queued, queue one now.
    DrmCompositionPlane *precomp = GetPrecomp(composition);
    if (precomp) {
      precomp->source_layers().emplace_back(i->first);
    } else {
      if (!planes->empty()) {
        DrmPlane *precomp_plane = planes->back();
        planes->pop_back();
        composition->emplace_back(DrmCompositionPlane::Type::kPrecomp,
                                  precomp_plane, crtc, i->first);
      } else {
        ALOGE("Not enough planes to reserve for precomp fb");
      }
    }
    i = layers.erase(i);
  }
  return 0;
}

int PlanStagePrecomp::ProvisionPlanes(
    std::vector<DrmCompositionPlane> *composition,
    std::map<size_t, DrmHwcLayer *> &layers, DrmCrtc *crtc,
    std::vector<DrmPlane *> *planes) {
  DrmCompositionPlane *precomp = GetPrecomp(composition);
  if (!precomp || precomp->source_layers().empty())
    return 0;

  // Find lowest zorder out of precomp layers
  size_t precomp_zorder = *std::min_element(
      precomp->source_layers().begin(), precomp->source_layers().end(),
      [](size_t a, size_t b) { return a < b; });

  // if there are any remaining layers on top of any of the precomp layers,
  // add them to precomp to avoid blending issues since precomp is always at
  // highest zorder
  for (auto i = layers.begin(); i != layers.end();) {
    if (i->first < precomp_zorder) {
      i++;
      continue;
    }
    precomp->source_layers().emplace_back(i->first);
    i = layers.erase(i);
  }

  return 0;
}

int PlanStageGreedy::ProvisionPlanes(
    std::vector<DrmCompositionPlane> *composition,
    std::map<size_t, DrmHwcLayer *> &layers, DrmCrtc *crtc,
    std::vector<DrmPlane *> *planes) {
  // Fill up the remaining planes
  for (auto i = layers.begin(); i != layers.end(); i = layers.erase(i)) {
    int ret = Emplace(composition, planes, DrmCompositionPlane::Type::kLayer,
                      crtc, i->first);
    // We don't have any planes left
    if (ret == -ENOENT)
      break;
    else if (ret)
      ALOGE("Failed to emplace layer %zu, dropping it", i->first);
  }

  // Put the rest of the layers in the precomp plane
  DrmCompositionPlane *precomp = GetPrecomp(composition);
  if (precomp) {
    for (auto i = layers.begin(); i != layers.end(); i = layers.erase(i))
      precomp->source_layers().emplace_back(i->first);
  }

  return 0;
}
}