// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/ozone/platform/drm/gpu/drm_gpu_display_manager.h"

#include "ui/display/types/gamma_ramp_rgb_entry.h"
#include "ui/ozone/common/display_util.h"
#include "ui/ozone/platform/drm/common/drm_util.h"
#include "ui/ozone/platform/drm/gpu/drm_device.h"
#include "ui/ozone/platform/drm/gpu/drm_device_manager.h"
#include "ui/ozone/platform/drm/gpu/drm_display.h"
#include "ui/ozone/platform/drm/gpu/screen_manager.h"

namespace ui {

namespace {

class DisplayComparator {
 public:
  explicit DisplayComparator(const DrmDisplay* display)
      : drm_(display->drm()),
        crtc_(display->crtc()),
        connector_(display->connector()) {}

  DisplayComparator(const scoped_refptr<DrmDevice>& drm,
                    uint32_t crtc,
                    uint32_t connector)
      : drm_(drm), crtc_(crtc), connector_(connector) {}

  bool operator()(const DrmDisplay* other) const {
    return drm_ == other->drm() && connector_ == other->connector() &&
           crtc_ == other->crtc();
  }

 private:
  scoped_refptr<DrmDevice> drm_;
  uint32_t crtc_;
  uint32_t connector_;
};

bool FindMatchingMode(const std::vector<drmModeModeInfo> modes,
                      const DisplayMode_Params& mode_params,
                      drmModeModeInfo* mode) {
  for (const drmModeModeInfo& m : modes) {
    DisplayMode_Params params = CreateDisplayModeParams(m);
    if (mode_params.size == params.size &&
        mode_params.refresh_rate == params.refresh_rate &&
        mode_params.is_interlaced == params.is_interlaced) {
      *mode = m;
      return true;
    }
  }

  return false;
}

}  // namespace

DrmGpuDisplayManager::DrmGpuDisplayManager(ScreenManager* screen_manager,
                                           DrmDeviceManager* drm_device_manager)
    : screen_manager_(screen_manager), drm_device_manager_(drm_device_manager) {
}

DrmGpuDisplayManager::~DrmGpuDisplayManager() {
}

std::vector<DisplaySnapshot_Params> DrmGpuDisplayManager::GetDisplays() {
  ScopedVector<DrmDisplay> old_displays(displays_.Pass());
  std::vector<DisplaySnapshot_Params> params_list;

  const DrmDeviceVector& devices = drm_device_manager_->GetDrmDevices();
  // Unique identifier used to create the display id.
  size_t index = 0;
  for (const auto& drm : devices) {
    ScopedVector<HardwareDisplayControllerInfo> display_infos =
        GetAvailableDisplayControllerInfos(drm->get_fd());
    for (auto* display_info : display_infos) {
      auto it = std::find_if(
          old_displays.begin(), old_displays.end(),
          DisplayComparator(drm, display_info->crtc()->crtc_id,
                            display_info->connector()->connector_id));
      if (it != old_displays.end()) {
        displays_.push_back(*it);
        old_displays.weak_erase(it);
      } else {
        displays_.push_back(new DrmDisplay(screen_manager_, drm));
      }

      params_list.push_back(displays_.back()->Update(display_info, index++));
    }
  }

  NotifyScreenManager(displays_.get(), old_displays.get());
  return params_list;
}

bool DrmGpuDisplayManager::TakeDisplayControl() {
  const DrmDeviceVector& devices = drm_device_manager_->GetDrmDevices();
  for (const auto& drm : devices) {
    if (!drm->SetMaster()) {
      LOG(ERROR) << "Failed to take control of the display";
      return false;
    }
  }

  return true;
}

bool DrmGpuDisplayManager::RelinquishDisplayControl() {
  const DrmDeviceVector& devices = drm_device_manager_->GetDrmDevices();
  for (const auto& drm : devices) {
    if (!drm->DropMaster()) {
      LOG(ERROR) << "Failed to relinquish control of the display";
      return false;
    }
  }

  return true;
}

bool DrmGpuDisplayManager::ConfigureDisplay(
    int64_t display_id,
    const DisplayMode_Params& mode_param,
    const gfx::Point& origin) {
  DrmDisplay* display = FindDisplay(display_id);
  if (!display) {
    LOG(ERROR) << "There is no display with ID " << display_id;
    return false;
  }

  drmModeModeInfo mode;
  bool mode_found = FindMatchingMode(display->modes(), mode_param, &mode);
  if (!mode_found) {
    // If the display doesn't have the mode natively, then lookup the mode from
    // other displays and try using it on the current display (some displays
    // support panel fitting and they can use different modes even if the mode
    // isn't explicitly declared).
    for (DrmDisplay* other : displays_) {
      mode_found = FindMatchingMode(other->modes(), mode_param, &mode);
      if (mode_found)
        break;
    }
  }

  if (!mode_found) {
    LOG(ERROR) << "Failed to find mode: size=" << mode_param.size.ToString()
               << " is_interlaced=" << mode_param.is_interlaced
               << " refresh_rate=" << mode_param.refresh_rate;
    return false;
  }

  return display->Configure(&mode, origin);
}

bool DrmGpuDisplayManager::DisableDisplay(int64_t display_id) {
  DrmDisplay* display = FindDisplay(display_id);
  if (!display) {
    LOG(ERROR) << "There is no display with ID " << display_id;
    return false;
  }

  return display->Configure(nullptr, gfx::Point());
}

bool DrmGpuDisplayManager::GetHDCPState(int64_t display_id, HDCPState* state) {
  DrmDisplay* display = FindDisplay(display_id);
  if (!display) {
    LOG(ERROR) << "There is no display with ID " << display_id;
    return false;
  }

  return display->GetHDCPState(state);
}

bool DrmGpuDisplayManager::SetHDCPState(int64_t display_id, HDCPState state) {
  DrmDisplay* display = FindDisplay(display_id);
  if (!display) {
    LOG(ERROR) << "There is no display with ID " << display_id;
    return false;
  }

  return display->SetHDCPState(state);
}

void DrmGpuDisplayManager::SetGammaRamp(
    int64_t display_id,
    const std::vector<GammaRampRGBEntry>& lut) {
  DrmDisplay* display = FindDisplay(display_id);
  if (!display) {
    LOG(ERROR) << "There is no display with ID " << display_id;
    return;
  }

  display->SetGammaRamp(lut);
}

DrmDisplay* DrmGpuDisplayManager::FindDisplay(int64_t display_id) {
  for (DrmDisplay* display : displays_)
    if (display->display_id() == display_id)
      return display;

  return nullptr;
}

void DrmGpuDisplayManager::NotifyScreenManager(
    const std::vector<DrmDisplay*>& new_displays,
    const std::vector<DrmDisplay*>& old_displays) const {
  for (size_t i = 0; i < old_displays.size(); ++i) {
    const std::vector<DrmDisplay*>::const_iterator it =
        std::find_if(new_displays.begin(), new_displays.end(),
                     DisplayComparator(old_displays[i]));

    if (it == new_displays.end()) {
      screen_manager_->RemoveDisplayController(old_displays[i]->drm(),
                                               old_displays[i]->crtc());
    }
  }

  for (size_t i = 0; i < new_displays.size(); ++i) {
    const std::vector<DrmDisplay*>::const_iterator it =
        std::find_if(old_displays.begin(), old_displays.end(),
                     DisplayComparator(new_displays[i]));

    if (it == old_displays.end()) {
      screen_manager_->AddDisplayController(new_displays[i]->drm(),
                                            new_displays[i]->crtc(),
                                            new_displays[i]->connector());
    }
  }
}

}  // namespace ui