src/heatmap.cpp

/* Copyright 2025 Mike Becker. All rights reserved.
*
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "heatmap.h"

#include <charconv>
#include <ranges>
#include <chrono>

namespace chrono = std::chrono;

void fm::heatmap::add(const settings &settings, const std::string &log) {
    using std::string_view_literals::operator ""sv;
    const std::string repo_key = m_separate ? m_current_repo : "All Repositories";

    for (auto line: std::views::split(log, "\n"sv)) {
        if (line.empty()) continue;

        // split the line by delimiter
        // this needs to be so crappy, because C++ split does not have a max-split parameter
        const auto line_view = std::string_view{line};
        const auto pos_delim1 = line_view.find('#', 0);
        const auto pos_delim2 = line_view.find('#', pos_delim1 + 1);
        const auto pos_delim3 = line_view.find('#', pos_delim2 + 1);
        const auto pos_delim4 = line_view.find('#', pos_delim3 + 1);

        std::string_view hash_view{line_view.substr(0, pos_delim1)};
        std::string author{line_view.substr(pos_delim1+1, pos_delim2 - pos_delim1 - 1)};
        std::string_view date_view{line_view.substr(pos_delim2+1, pos_delim3 - pos_delim2 - 1)};
        std::string_view tags_view{line_view.substr(pos_delim3+1, pos_delim4 - pos_delim3 - 1)};
        std::string_view summary_view{line_view.substr(pos_delim4+1)};

        int year = 0;
        unsigned int month = 0, day = 0;
        auto date_parts = std::views::split(date_view, "-"sv)
                          | std::views::transform([](auto r) { return std::string_view(r); })
                          | std::ranges::to<std::vector>();
        std::from_chars(date_parts[0].begin(), date_parts[0].end(), year);
        std::from_chars(date_parts[1].begin(), date_parts[1].end(), month);
        std::from_chars(date_parts[2].begin(), date_parts[2].end(), day);
        auto &[summaries, tags] =
                m_heatmap[repo_key][author][chrono::year_month_day{
                    chrono::year{year}, chrono::month{month}, chrono::day{day}
                }];
        summaries[m_current_repo].emplace_back(hash_view, summary_view);
        // special case: if the (only) tag is "tip", we do not add it
        if (!tags_view.empty() && tags_view != "tip") {
            tags[m_current_repo].emplace_back(hash_view, tags_view);
        }
    }
}

std::array<fm::commit_summary, 12> fm::heatmap::commits_per_month(
    const std::string& repo,
    const std::string& author,
    chrono::year year
) const {
    std::array<commit_summary, 12> result{};
    for (auto &&[ymd, commits]: m_heatmap.at(repo).at(author)) {
        if (ymd.year() != year) continue;
        commit_summary &cs = result[static_cast<unsigned int>(ymd.month()) - 1];
        for (auto &&[reponame, summaries]: commits.summaries) {
            cs.commits[reponame] += summaries.size();
        }
        for (auto &&[reponame, tags]: commits.tags) {
            if (tags.empty()) continue;
            std::string tag_list = tags.at(0).message;
            for (unsigned i = 1; i < tags.size(); ++i) {
                tag_list.append(", ");
                tag_list.append(tags.at(i).message);
            }
            cs.tags_with_date[reponame].emplace_back(
                    std::format("{} on {}-{:02}-{:02}",
                                tag_list,
                                static_cast<int>(ymd.year()),
                                static_cast<unsigned>(ymd.month()),
                                static_cast<unsigned>(ymd.day())));
        }
    }
    return result;
}