// Copyright (c) 2017-2025, University of Cincinnati, developed by Henry Schreiner
// under NSF AWARD 1414736 and by the respective contributors.
// All rights reserved.
//
// SPDX-License-Identifier: BSD-3-Clause

// Code inspired by discussion from https://github.com/CLIUtils/CLI11/issues/1149

#include <CLI/CLI.hpp>
#include <iostream>
#include <limits>
#include <string>
#include <vector>
#include <utility>

// Levenshtein distance function code generated by chatgpt
int levenshteinDistance(const std::string &s1, const std::string &s2) {
    size_t len1 = s1.size(), len2 = s2.size();
    std::vector<std::vector<int>> dp(len1 + 1, std::vector<int>(len2 + 1));

    for(size_t i = 0; i <= len1; ++i)
        dp[i][0] = static_cast<int>(i);
    for(size_t j = 0; j <= len2; ++j)
        dp[0][j] = static_cast<int>(j);

    for(size_t i = 1; i <= len1; ++i) {
        for(size_t j = 1; j <= len2; ++j) {
            int cost = (s1[i - 1] == s2[j - 1]) ? 0 : 1;
            dp[i][j] = (std::min)({
                dp[i - 1][j] + 1,        // deletion
                dp[i][j - 1] + 1,        // insertion
                dp[i - 1][j - 1] + cost  // substitution
            });
        }
    }

    return dp[len1][len2];
}

// Finds the closest string from a list (modified from chat gpt code)
std::pair<std::string, int> findClosestMatch(const std::string &input, const std::vector<std::string> &candidates) {
    std::string closest;
    int minDistance = (std::numeric_limits<int>::max)();

    for(const auto &candidate : candidates) {
        int distance = levenshteinDistance(input, candidate);
        if(distance < minDistance) {
            minDistance = distance;
            closest = candidate;
        }
    }

    return {closest, minDistance};
}

/** This example demonstrates the use of `prefix_command` on a subcommand
to capture all subsequent arguments along with an alias to make it appear as a regular options.

All the values after the "sub" or "--sub" are available in the remaining() method.
*/
int main(int argc, const char *argv[]) {

    int value{0};
    CLI::App app{"cose string App"};
    app.add_option("-v", value, "value");

    app.add_subcommand("install", "");
    app.add_subcommand("upgrade", "");
    app.add_subcommand("remove", "");
    app.add_subcommand("test", "");
    app.allow_extras(true);

    app.parse_complete_callback([&app]() {
        auto extras = app.remaining();
        if(extras.empty()) {
            return;
        }
        auto subs = app.get_subcommands(nullptr);
        std::vector<std::string> list;
        for(const auto *sub : subs) {
            if(!sub->get_name().empty()) {
                list.push_back(sub->get_name());
            }
            auto aliases = sub->get_aliases();
            if(!aliases.empty()) {
                list.insert(list.end(), aliases.begin(), aliases.end());
            }
        }
        for(auto &extra : extras) {
            if(extra.front() != '-') {
                auto closest = findClosestMatch(extra, list);
                if(closest.second <= 3) {
                    std::cout << "unmatched commands " << extra << ", closest match is " << closest.first << "\n";
                }
            }
        }
    });
    CLI11_PARSE(app, argc, argv);
    return 0;
}