/*
 *  nextpnr -- Next Generation Place and Route
 *
 *  Copyright (C) 2018  Miodrag Milanovic <miodrag@symbioticeda.com>
 *  Copyright (C) 2018  Serge Bazanski <q3k@symbioticeda.com>
 *
 *  Permission to use, copy, modify, and/or distribute this software for any
 *  purpose with or without fee is hereby granted, provided that the above
 *  copyright notice and this permission notice appear in all copies.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

#include "treemodel.h"
#include "log.h"

NEXTPNR_NAMESPACE_BEGIN

namespace TreeModel {

// converts 'aa123bb432' -> ['aa', '123', 'bb', '432']
std::vector<QString> IdList::alphaNumSplit(const QString &str)
{
    std::vector<QString> res;
    QString current_part;

    bool number = true;
    for (const auto c : str) {
        if (current_part.size() == 0 && res.size() == 0) {
            current_part.push_back(c);
            number = c.isNumber();
            continue;
        }

        if (number != c.isNumber()) {
            number = c.isNumber();
            res.push_back(current_part);
            current_part.clear();
        }

        current_part.push_back(c);
    }

    res.push_back(current_part);

    return res;
}

void IdList::updateElements(Context *ctx, std::vector<IdStringList> elements)
{
    bool changed = false;

    // For any elements that are not yet in managed_, created them.
    std::unordered_set<IdStringList> element_set;
    for (auto elem : elements) {
        element_set.insert(elem);
        auto existing = managed_.find(elem);
        if (existing == managed_.end()) {
            auto item = new IdStringItem(ctx, elem, this, child_type_);
            managed_.emplace(elem, std::unique_ptr<IdStringItem>(item));
            changed = true;
        }
    }

    // For any elements that are in managed_ but not in new, delete them.
    auto it = managed_.begin();
    while (it != managed_.end()) {
        if (element_set.count(it->first) != 0) {
            ++it;
        } else {
            it = managed_.erase(it);
            changed = true;
        }
    }

    // Return early if there are no changes.
    if (!changed)
        return;

    // Rebuild children list.
    children_.clear();
    for (auto &pair : managed_) {
        if (element_set.count(pair.first) != 0) {
            children_.push_back(pair.second.get());
        }
    }

    // Sort new children
    std::sort(children_.begin(), children_.end(), [&](const Item *a, const Item *b) {
        auto parts_a = alphaNumSplit(a->name());
        auto parts_b = alphaNumSplit(b->name());

        for (size_t i = 0; i < parts_a.size() && i < parts_b.size(); i++) {
            auto &part_a = parts_a.at(i);
            auto &part_b = parts_b.at(i);

            bool a_is_number, b_is_number;
            int a_number = part_a.toInt(&a_is_number);
            int b_number = part_b.toInt(&b_is_number);

            // If both parts are numbers, compare numerically.
            // If they're equal, continue to next part.
            if (a_is_number && b_is_number) {
                if (a_number != b_number) {
                    return a_number < b_number;
                } else {
                    continue;
                }
            }

            // For different alpha/nonalpha types, make numeric parts appear
            // first.
            if (a_is_number != b_is_number) {
                return a_is_number;
            }

            // If both parts are numbers, compare lexically.
            // If they're equal, continue to next part.
            if (part_a == part_b) {
                continue;
            }
            return part_a < part_b;
        }

        // One string is equal to or a subset of the other, compare length.
        return parts_a.size() < parts_b.size();
    });
}

void IdList::search(QList<Item *> &results, QString text, int limit)
{
    for (const auto &child : children_) {
        if (limit != -1 && results.size() > limit)
            return;

        if (child->name().contains(text))
            results.push_back(child);
    }
}

Model::Model(QObject *parent) : QAbstractItemModel(parent), root_(new Item("Elements", nullptr)) {}

Model::~Model() {}

void Model::loadData(Context *ctx, std::unique_ptr<Item> data)
{
    beginResetModel();
    ctx_ = ctx;
    root_ = std::move(data);
    endResetModel();
}

void Model::updateElements(std::vector<IdStringList> elements)
{
    if (!ctx_)
        return;

    beginResetModel();
    root_->updateElements(ctx_, elements);
    endResetModel();
}

int Model::rowCount(const QModelIndex &parent) const { return nodeFromIndex(parent)->count(); }

int Model::columnCount(const QModelIndex &parent) const { return 1; }

QModelIndex Model::index(int row, int column, const QModelIndex &parent) const
{
    Item *node = nodeFromIndex(parent);
    if (row >= node->count())
        return QModelIndex();

    return createIndex(row, column, node->child(row));
}

QModelIndex Model::parent(const QModelIndex &child) const
{
    Item *parent = nodeFromIndex(child)->parent();
    if (parent == root_.get())
        return QModelIndex();
    Item *node = parent->parent();
    return createIndex(node->indexOf(parent), 0, parent);
}

QVariant Model::data(const QModelIndex &index, int role) const
{
    if (index.column() != 0)
        return QVariant();
    if (role != Qt::DisplayRole)
        return QVariant();
    Item *node = nodeFromIndex(index);
    return node->name();
}

QVariant Model::headerData(int section, Qt::Orientation orientation, int role) const
{
    Q_UNUSED(section);
    if (orientation == Qt::Horizontal && role == Qt::DisplayRole)
        return QString("Items");

    return QVariant();
}

Item *Model::nodeFromIndex(const QModelIndex &idx) const
{
    if (idx.isValid())
        return (Item *)idx.internalPointer();
    return root_.get();
}

Qt::ItemFlags Model::flags(const QModelIndex &index) const
{
    Item *node = nodeFromIndex(index);
    return Qt::ItemIsEnabled | (node->type() != ElementType::NONE ? Qt::ItemIsSelectable : Qt::NoItemFlags);
}

void Model::fetchMore(const QModelIndex &parent)
{
    if (ctx_ == nullptr)
        return;

    std::lock_guard<std::mutex> lock_ui(ctx_->ui_mutex);
    std::lock_guard<std::mutex> lock(ctx_->mutex);

    nodeFromIndex(parent)->fetchMore();
}

bool Model::canFetchMore(const QModelIndex &parent) const { return nodeFromIndex(parent)->canFetchMore(); }

QList<QModelIndex> Model::search(QString text)
{
    const int limit = 500;
    QList<Item *> list;
    root_->search(list, text, limit);

    QList<QModelIndex> res;
    for (auto i : list) {
        res.push_back(indexFromNode(i));
    }
    return res;
}

}; // namespace TreeModel

NEXTPNR_NAMESPACE_END
