//
// Copyright (c) 2008-2015 the Urho3D project.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

#include "../../Core/CoreEvents.h"
#include "../../Core/Profiler.h"
#include "../../Engine/Engine.h"
#include "../../Graphics/Graphics.h"
#include "../../Graphics/Renderer.h"
#include "../../IO/Log.h"
#include "Font.h"
#include "Text.h"
#include "SystemUI.h"
#include "UIElement.h"
#include "DebugHud.h"

#include "../../DebugNew.h"

namespace Atomic
{

namespace SystemUI
{

static const char* qualityTexts[] =
{
    "Low",
    "Med",
    "High"
};

static const char* shadowQualityTexts[] =
{
    "16bit Low",
    "24bit Low",
    "16bit High",
    "24bit High"
};

static const float FPS_UPDATE_INTERVAL = 0.5f;

DebugHud::DebugHud(Context* context) :
    Object(context),
    profilerMaxDepth_(M_MAX_UNSIGNED),
    profilerInterval_(1000),
    useRendererStats_(true),
    mode_(DEBUGHUD_SHOW_NONE),
    fpsTimeSinceUpdate_(FPS_UPDATE_INTERVAL),
    fpsFramesSinceUpdate_(0),
    fps_(0)
{
    SystemUI* ui = GetSubsystem<SystemUI>();
    UIElement* uiRoot = ui->GetRoot();

    layout_ = new UIElement(context_);
    uiRoot->AddChild(layout_);

    layout_->SetSize(uiRoot->GetSize());

    statsText_ = new Text(context_);
    statsText_->SetAlignment(HA_LEFT, VA_TOP);
    statsText_->SetPriority(100);
    statsText_->SetVisible(false);
    layout_->AddChild(statsText_);

    modeText_ = new Text(context_);
    modeText_->SetAlignment(HA_LEFT, VA_BOTTOM);
    modeText_->SetPriority(100);
    modeText_->SetVisible(false);
    layout_->AddChild(modeText_);

    profilerText_ = new Text(context_);
    profilerText_->SetAlignment(HA_RIGHT, VA_TOP);
    profilerText_->SetPriority(100);
    profilerText_->SetVisible(false);
    layout_->AddChild(profilerText_);

    SubscribeToEvent(E_POSTUPDATE, ATOMIC_HANDLER(DebugHud, HandlePostUpdate));
}

DebugHud::~DebugHud()
{
    statsText_->Remove();
    modeText_->Remove();
    profilerText_->Remove();
}

void DebugHud::SetExtents(bool useRootExtents, const IntVector2& position, const IntVector2& size)
{
    if (useRootExtents)
    {
        SystemUI* ui = GetSubsystem<SystemUI>();
        UIElement* uiRoot = ui->GetRoot();

        layout_->SetPosition(IntVector2::ZERO);
        layout_->SetSize(uiRoot->GetSize());
    }
    else
    {
        layout_->SetPosition(position);
        layout_->SetSize(size);
    }
}

void DebugHud::Update(float timeStep)
{
    Graphics* graphics = GetSubsystem<Graphics>();
    Renderer* renderer = GetSubsystem<Renderer>();
    if (!renderer || !graphics)
        return;

    // Ensure UI-elements are not detached
    if (!layout_->GetParent())
    {
        SystemUI* ui = GetSubsystem<SystemUI>();
        UIElement* uiRoot = ui->GetRoot();
        uiRoot->AddChild(layout_);
    }

    if (statsText_->IsVisible())
    {
        fpsTimeSinceUpdate_ += timeStep;
        ++fpsFramesSinceUpdate_;
        if (fpsTimeSinceUpdate_ > FPS_UPDATE_INTERVAL)
        {
            fps_ = (int)(fpsFramesSinceUpdate_ / fpsTimeSinceUpdate_);
            fpsFramesSinceUpdate_ = 0;
            fpsTimeSinceUpdate_ = 0;
        }

        unsigned primitives, batches;
        if (!useRendererStats_)
        {
            primitives = graphics->GetNumPrimitives();
            batches = graphics->GetNumBatches();
        }
        else
        {
            primitives = renderer->GetNumPrimitives();
            batches = renderer->GetNumBatches();
        }

        String stats;

        unsigned singlePassPrimitives = graphics->GetSinglePassPrimitives();
        unsigned editorPrimitives = graphics->GetNumPrimitives() - renderer->GetNumPrimitives();

        if (singlePassPrimitives)
            stats.AppendWithFormat("FPS %d\nTriangles (All passes) %u\nTriangles (Single pass) %u\nTriangles (Editor) %u\n", 
                fps_, 
                primitives, 
                singlePassPrimitives, 
                editorPrimitives);
        else
            stats.AppendWithFormat("FPS %d\nTriangles %u\n", fps_, primitives);
                    
        stats.AppendWithFormat("Batches %u\nViews %u\nLights %u\nShadowmaps %u\nOccluders %u",
            batches,
            renderer->GetNumViews(),
            renderer->GetNumLights(true),
            renderer->GetNumShadowMaps(true),
            renderer->GetNumOccluders(true));

        if (!appStats_.Empty())
        {
            stats.Append("\n");
            for (HashMap<String, String>::ConstIterator i = appStats_.Begin(); i != appStats_.End(); ++i)
                stats.AppendWithFormat("\n%s %s", i->first_.CString(), i->second_.CString());
        }

        statsText_->SetText(stats);
    }

    if (modeText_->IsVisible())
    {
        String mode;
        mode.AppendWithFormat("Tex:%s Mat:%s Spec:%s Shadows:%s Size:%i Quality:%s Occlusion:%s Instancing:%s API:%s",
            qualityTexts[renderer->GetTextureQuality()],
            qualityTexts[renderer->GetMaterialQuality()],
            renderer->GetSpecularLighting() ? "On" : "Off",
            renderer->GetDrawShadows() ? "On" : "Off",
            renderer->GetShadowMapSize(),
            shadowQualityTexts[renderer->GetShadowQuality()],
            renderer->GetMaxOccluderTriangles() > 0 ? "On" : "Off",
            renderer->GetDynamicInstancing() ? "On" : "Off",
            graphics->GetApiName().CString());

        modeText_->SetText(mode);
    }

    Profiler* profiler = GetSubsystem<Profiler>();
    if (profiler)
    {
        if (profilerTimer_.GetMSec(false) >= profilerInterval_)
        {
            profilerTimer_.Reset();

            if (profilerText_->IsVisible())
            {
                String profilerOutput = profiler->PrintData(false, false, profilerMaxDepth_);
                profilerText_->SetText(profilerOutput);
            }

            profiler->BeginInterval();
        }
    }
}

void DebugHud::SetDefaultStyle(XMLFile* style)
{
    if (!style)
        return;

    statsText_->SetDefaultStyle(style);
    statsText_->SetStyle("DebugHudText");
    modeText_->SetDefaultStyle(style);
    modeText_->SetStyle("DebugHudText");
    profilerText_->SetDefaultStyle(style);
    profilerText_->SetStyle("DebugHudText");
}

void DebugHud::SetMode(unsigned mode)
{
    statsText_->SetVisible((mode & DEBUGHUD_SHOW_STATS) != 0);
    modeText_->SetVisible((mode & DEBUGHUD_SHOW_MODE) != 0);
    profilerText_->SetVisible((mode & DEBUGHUD_SHOW_PROFILER) != 0);

    mode_ = mode;
}

void DebugHud::CycleMode()
{
    switch (mode_)
    {
    case DEBUGHUD_SHOW_NONE:
        SetMode(DEBUGHUD_SHOW_STATS);
        break;
    case DEBUGHUD_SHOW_STATS:
        SetMode(DEBUGHUD_SHOW_MODE);
        break;
    case DEBUGHUD_SHOW_MODE:
        SetMode(DEBUGHUD_SHOW_PROFILER);
        break;
    case DEBUGHUD_SHOW_PROFILER:
        SetMode(DEBUGHUD_SHOW_ALL);
        break;
    case DEBUGHUD_SHOW_ALL:
    default:
        SetMode(DEBUGHUD_SHOW_NONE);
        break;
    }
}

void DebugHud::SetProfilerMaxDepth(unsigned depth)
{
    profilerMaxDepth_ = depth;
}

void DebugHud::SetProfilerInterval(float interval)
{
    profilerInterval_ = (unsigned)Max((int)(interval * 1000.0f), 0);
}

void DebugHud::SetUseRendererStats(bool enable)
{
    useRendererStats_ = enable;
}

void DebugHud::Toggle(unsigned mode)
{
    SetMode(GetMode() ^ mode);
}

void DebugHud::ToggleAll()
{
    Toggle(DEBUGHUD_SHOW_ALL);
}

XMLFile* DebugHud::GetDefaultStyle() const
{
    return statsText_->GetDefaultStyle(false);
}

float DebugHud::GetProfilerInterval() const
{
    return (float)profilerInterval_ / 1000.0f;
}

void DebugHud::SetAppStats(const String& label, const Variant& stats)
{
    SetAppStats(label, stats.ToString());
}

void DebugHud::SetAppStats(const String& label, const String& stats)
{
    bool newLabel = !appStats_.Contains(label);
    appStats_[label] = stats;
    if (newLabel)
        appStats_.Sort();
}

bool DebugHud::ResetAppStats(const String& label)
{
    return appStats_.Erase(label);
}

void DebugHud::ClearAppStats()
{
    appStats_.Clear();
}

void DebugHud::HandlePostUpdate(StringHash eventType, VariantMap& eventData)
{
    using namespace PostUpdate;

    Update(eventData[P_TIMESTEP].GetFloat());
}

}

}