var Botkit = require('botkit');
var controller = Botkit.slackbot({
    json_file_store: process.argv[3]
});
var bot = controller.spawn({
    token: process.argv[2]
})
var problems = [
    {"title": "Travelling salesman problem", "wiki_title": "Travelling_salesman_problem"},
    {"title": "Knapsack problem", "wiki_title": "Knapsack_problem"},
    {"title": "Bin packing problem", "wiki_title": "Bin_packing_problem"},
    {"title": "Partition problem", "wiki_title": "Parition_problem"},
    {"title": "Longest path problem", "wiki_title": "Longest_path_problem"},
    {"title": "Longest common subsequence problem"},
    {"title": "Art gallery problem"},
    {"title": "Route inspection problem"},
    {"title": "Calculated minimum spanning tree"}
]

var last_index = -1;
var test_channel_id = "C0NEYDD16";

bot.startRTM(function(err,bot,payload) {
    if (err) {
        throw new Error('Could not connect to Slack');
    }
});

function createData(id) {
    return {id: id, bot_calls: 0};
};

function incrementKey(id, key, amount, scope) {
    controller.storage[scope].get(id, function(err,data) {
        if (!data) {
            console.log("Initializing " + scope + " data");
            data = createData(id);
        }
        console.log("Current " + scope + " data:",data);
        console.log("Incrementing mentions to " + (data[key] + amount));
        data[key] = data[key] + amount
        controller.storage[scope].save(data);
    });
}

controller.hears(["np"],["direct_message","direct_mention","mention","ambient"],function(bot,message) {
    console.log(message.user + " mentioned \"np\"");

    // Increment the logged amount of mentions
    if (message.channel != test_channel_id) {
        incrementKey(message.channel, "bot_calls", 1, "channels");
        incrementKey(message.team, "bot_calls", 1, "teams");
        incrementKey(message.user, "bot_calls", 1, "users");
    } else {
        console.log("Message was from test channel! Mention counters will not be increased.");
    }

    // Decide what to do
    if (Math.random() < 0.9) {
        var index = Math.floor(Math.random() * problems.length);
        var base_url = "https://en.wikipedia.org/wiki/";
        var problem, title, wiki_title;

        // Ensure that the same problem won't get posted twice
        while (index == last_index && problems.length > 1) {
            index = Math.floor(Math.random() * problems.length);
        }

        // Find the problem metadata
        problem = problems[index];
        title = problem.title;
        wiki_title = title.replace(/ /g,"_");

        // Reply with the chosen problem
        bot.reply(message,"Have you heard about the _" + title + "_? That is an NP-complete problem!\nSee " + base_url + wiki_title + " for more info!");
        last_index = index;
    } else {
        bot.say(
            {
                text: '<@U0NEAMJS3|jonbot>, what do you think about NP-complete problems?',
                channel: message.channel
            }
        );
    }

    // React with appropriate emoji
    bot.api.reactions.add({
        timestamp: message.ts,
        channel: message.channel,
        name: "mount_fuji",
    },function(err, res) {
        if (err) {
            bot.botkit.log('Failed to add reaction emoji');
        }
    });
});