#include "timeline.h"
#include "note.h"

#include <SFML/Graphics/RenderTarget.hpp>
#include <iostream>

Timeline::Timeline()
{
    // BPM of METEOR is 170.
    // Length is 1:14
    // I calculated that the time between beats is about 1412162 microseconds

    _timeline.reserve(1000);

    microsec starting_beat_offset = 372162;
    int amount_of_beats = 209;
    microsec interval = 1412162;
    microsec note_input_offset = 412162;
    microsec bpm_iterator = starting_beat_offset;
    microsec bpm_end = starting_beat_offset + (interval * amount_of_beats);
    _visibility_offset = note_input_offset * 3;

    Note::resetPrecisionQualifier(note_input_offset / 3);

    while (bpm_iterator < bpm_end)
    {
        _timeline.emplace_back(new Note(bpm_iterator, note_input_offset));
        bpm_iterator += interval;
    }

    _timeline[0]->setPosition({200, 200});
    _timeline[1]->setPosition({250, 200});
    _timeline[2]->setPosition({300, 200});
    _timeline[3]->setPosition({350, 200});
    _timeline[4]->setPosition({400, 200});
    _timeline[5]->setPosition({450, 200});
    _timeline[6]->setPosition({200, 300});
    _timeline[7]->setPosition({250, 300});
    _timeline[8]->setPosition({300, 300});
    _timeline[9]->setPosition({350, 300});
    _timeline[10]->setPosition({400, 300});
    _timeline[11]->setPosition({450, 300});

    _active_note = nullptr;
    _last_visible_note = _timeline.end();
    _top_note = _timeline.begin();

    prepareNotesToDraw(0);
}

void Timeline::prepareNotesToDraw(const microsec &music_offset)
{
    auto note_iterator = _top_note;

    while (((*note_iterator)->offset() - _visibility_offset) >= music_offset)
        ++note_iterator;

    _last_visible_note = note_iterator;
}

Timeline::~Timeline()
{
    clear();
}

void Timeline::clear()
{
    for (auto note : _timeline)
        delete note;

    _timeline.clear();
    _top_note = _timeline.end();
    _last_visible_note = _timeline.end();
    _active_note = nullptr;

    Note::resetPrecisionQualifier();
}

static sf::RectangleShape createNoteGlyph(const std::vector<Note*>::const_iterator& note_to_draw)
{                              // Temporary solution
    sf::RectangleShape ret;
    const auto position = (*note_to_draw)->position();
    ret.setPosition(position.x, position.y);
    ret.setFillColor(sf::Color(255, 100, 0));
    ret.setSize({10.f, 10.f});
    return ret;
}

void Timeline::draw(sf::RenderTarget& target, sf::RenderStates states) const  // Temporary solution
{
    if (_last_visible_note == _timeline.end() || _top_note > _last_visible_note)
        return;

    auto note_to_draw = _top_note;
    while (note_to_draw != (_last_visible_note + 1))
    {
        target.draw(createNoteGlyph(note_to_draw), states);
        ++note_to_draw;
    }
}

void Timeline::update(const microsec &music_offset)
{
    checkCurrentActiveNote(music_offset);
    checkForNextActiveNote(music_offset);
    prepareNotesToDraw(music_offset);
}

void Timeline::checkCurrentActiveNote(const microsec &music_offset)
{
    if (_active_note && !_active_note->isActive(music_offset))
    {
        _active_note = nullptr;
        ++_top_note;
    }
}

void Timeline::checkForNextActiveNote(const microsec &music_offset)
{
    if (!_active_note && (*_top_note)->isActive(music_offset))
    {
        std::cout << "New active note: " << music_offset << '\n';
        _active_note = *_top_note;
    }
}

const Note* Timeline::fetchActiveNote(const microsec &music_offset) noexcept
{
    std::cout << "Clicked at: " << music_offset << '\n';
    update(music_offset);
    return _active_note;
}