const fs = require('fs');
const _ = require('underscore');

let storylines = {};
fs.readdirSync('./game/scenario/storylines').forEach(file => {
  require(`./storylines/${file}`)(storylines);
});

function l(context) {
  return _.keys(storylines);
}

function v(context) {
  return new Promise((resolve, reject) => {
    let ok = true;
    console.info(`[${context.id}] Verifying map integrity...`);
    let uniques = _.chain(context.scenario.map.locations)
      .map(location => location.id)
      .uniq().value();
    if(uniques.length !== context.scenario.map.locations.length) {
      console.error(`[${context.id}] ID collision detected`);
      reject(new Error("ID Collision in map data"));
    }
    _.each(context.scenario.map.connections, connection => {
      if(!_.contains(uniques, connection.locations[0])) {
        console.error(`[${context.id}] Invalid connection detected [${connection.locations[0]}]`);
        ok = false;
      } else if(!_.contains(uniques, connection.locations[1])) {
        console.error(`[${context.id}] Invalid connection detected [${connection.locations[1]}]`);
        ok = false;
      }
    });
    if(ok) {
      console.info(`[${context.id}] ... Verified map integrity`);
      resolve(context);
    } else {
      reject(new Error("Invalid map data"));
    }
  });
}

function i(context) {
  return new Promise((resolve, reject) => {
    if(!context.scenario) {
      if(context.storyline) {
        if(_.has(storylines, context.storyline)) {
          storylines[context.storyline].initialize(context)
            .then(context => {
              context.state.scenario = context.scenario;
              v(context)
                .then(context => {
                  context.message.reply(`Initiated scenario \`[${context.storyline}]\``)
                    .then(() => {
                      context.stateChanged = true;
                      resolve(context);
                    })
                    .catch(err => reject(err))
                })
                .catch(err => reject(err));
            })
            .catch(err => reject(err));
        } else {
          console.warn(`[${context.id}] No such storyline named ${context.storyline}.`)
          reject(new Error(`No such storyline named ${context.storyline}.`));
        }
      } else {
        console.error(`[${context.id}] Missing storyline context`);
        reject(new Error(`Invalid context`));
      }
    } else {
      console.warn(`[${context.id}] Scenario already initiated.`);
      reject(new Error(`Scenario already initiated.`));
    }
  });
}

module.exports = {
  init: i,
  list: l
}