/*
 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include "TimelineTrack.h"
#include "Profile.h"
#include "TimelineView.h"
#include <LibGUI/Painter.h>
#include <LibGfx/Font.h>
#include <LibGfx/Palette.h>

namespace Profiler {

TimelineTrack::TimelineTrack(TimelineView& view, Profile& profile, Process const& process)
    : m_view(view)
    , m_profile(profile)
    , m_process(process)
{
    set_fill_with_background_color(true);
    set_background_role(Gfx::ColorRole::Base);
    set_fixed_height(40);
    set_fixed_width(m_profile.length_in_ms() / 10);
    set_frame_thickness(1);
}

TimelineTrack::~TimelineTrack()
{
}

void TimelineTrack::paint_event(GUI::PaintEvent& event)
{
    GUI::Frame::paint_event(event);

    GUI::Painter painter(*this);
    painter.add_clip_rect(event.rect());

    const u64 start_of_trace = m_profile.first_timestamp();
    const u64 end_of_trace = start_of_trace + m_profile.length_in_ms();

    const auto clamp_timestamp = [start_of_trace, end_of_trace](u64 timestamp) -> u64 {
        return min(end_of_trace, max(timestamp, start_of_trace));
    };

    float column_width = (float)frame_inner_rect().width() / (float)m_profile.length_in_ms();
    float frame_height = (float)frame_inner_rect().height() / (float)m_profile.deepest_stack_depth();

    for (auto& event : m_profile.events()) {
        if (event.pid != m_process.pid)
            continue;

        if (!m_process.valid_at(event.timestamp))
            continue;

        u64 t = clamp_timestamp(event.timestamp) - start_of_trace;
        int x = (int)((float)t * column_width);
        int cw = max(1, (int)column_width);

        int column_height = frame_inner_rect().height() - (int)((float)event.frames.size() * frame_height);

        bool in_kernel = event.in_kernel;
        Color color = in_kernel ? Color::from_rgb(0xc25e5a) : Color::from_rgb(0x5a65c2);
        for (int i = 1; i <= cw; ++i)
            painter.draw_line({ x + i, frame_thickness() + column_height }, { x + i, height() - frame_thickness() * 2 }, color);
    }

    u64 normalized_start_time = clamp_timestamp(min(m_view.select_start_time(), m_view.select_end_time()));
    u64 normalized_end_time = clamp_timestamp(max(m_view.select_start_time(), m_view.select_end_time()));
    u64 normalized_hover_time = clamp_timestamp(m_view.hover_time());

    int select_start_x = (int)((float)(normalized_start_time - start_of_trace) * column_width);
    int select_end_x = (int)((float)(normalized_end_time - start_of_trace) * column_width);
    int select_hover_x = (int)((float)(normalized_hover_time - start_of_trace) * column_width);
    painter.fill_rect({ select_start_x, frame_thickness(), select_end_x - select_start_x, height() - frame_thickness() * 2 }, Color(0, 0, 0, 60));
    painter.fill_rect({ select_hover_x, frame_thickness(), 1, height() - frame_thickness() * 2 }, Color::NamedColor::Black);
}

u64 TimelineTrack::timestamp_at_x(int x) const
{
    float column_width = (float)frame_inner_rect().width() / (float)m_profile.length_in_ms();
    float ms_into_profile = (float)x / column_width;
    return m_profile.first_timestamp() + (u64)ms_into_profile;
}

void TimelineTrack::mousedown_event(GUI::MouseEvent& event)
{
    if (event.button() != GUI::MouseButton::Left)
        return;

    m_view.set_selecting({}, true);
    m_view.set_select_start_time({}, timestamp_at_x(event.x()));
    m_view.set_select_end_time({}, m_view.select_start_time());
    m_profile.set_timestamp_filter_range(m_view.select_start_time(), m_view.select_end_time());
    update();
}

void TimelineTrack::mousemove_event(GUI::MouseEvent& event)
{
    m_view.set_hover_time({}, timestamp_at_x(event.x()));

    if (m_view.is_selecting()) {
        m_view.set_select_end_time({}, m_view.hover_time());
        m_profile.set_timestamp_filter_range(m_view.select_start_time(), m_view.select_end_time());
    }

    update();
}

void TimelineTrack::mouseup_event(GUI::MouseEvent& event)
{
    if (event.button() != GUI::MouseButton::Left)
        return;

    m_view.set_selecting({}, false);
    if (m_view.select_start_time() == m_view.select_end_time())
        m_profile.clear_timestamp_filter_range();
}

}