///<reference path="../../headers/common.d.ts" />

import moment = require('moment');
import _ = require('lodash');
import angular = require('angular');

var spans = {
  's': {display: 'second'},
  'm': {display: 'minute'},
  'h': {display: 'hour'},
  'd': {display: 'day'},
  'w': {display: 'week'},
  'M': {display: 'month'},
  'y': {display: 'year'},
};

var rangeOptions = [
  { from: 'now/d',    to: 'now/d',    display: 'Today',                 section: 0 },
  { from: 'now/w',    to: 'now/w',    display: 'This week',             section: 0 },
  { from: 'now/d',    to: 'now',      display: 'The day so far',        section: 0 },
  { from: 'now/w',    to: 'now',      display: 'Week to date',          section: 0 },
  { from: 'now/M',    to: 'now/M',    display: 'This month',            section: 0 },
  { from: 'now/y',    to: 'now/y',    display: 'This year',             section: 0 },

  { from: 'now-1d/d', to: 'now-1d/d', display: 'Yesterday',             section: 1 },
  { from: 'now-2d/d', to: 'now-2d/d', display: 'Day before yesterday',  section: 1 },
  { from: 'now-7d/d', to: 'now-7d/d', display: 'This day last week',    section: 1 },
  { from: 'now-1w/w', to: 'now-1w/w', display: 'Previous week',         section: 1 },
  { from: 'now-1M/M', to: 'now-1M/M', display: 'Previous month',        section: 1 },
  { from: 'now-1y/y', to: 'now-1y/y', display: 'Previous year',         section: 1 },

  { from: 'now-5m',   to: 'now',      display: 'Last 5 minutes',        section: 2 },
  { from: 'now-15m',  to: 'now',      display: 'Last 15 minutes',       section: 2 },
  { from: 'now-30m',  to: 'now',      display: 'Last 30 minutes',       section: 2 },
  { from: 'now-1h',   to: 'now',      display: 'Last 1 hour',           section: 2 },
  { from: 'now-4h',   to: 'now',      display: 'Last 4 hours',          section: 2 },
  { from: 'now-12h',  to: 'now',      display: 'Last 12 hours',         section: 2 },
  { from: 'now-24h',  to: 'now',      display: 'Last 24 hours',         section: 2 },
  { from: 'now-7d',   to: 'now',      display: 'Last 7 days',           section: 2 },

  { from: 'now-30d',  to: 'now',      display: 'Last 30 days',          section: 3 },
  { from: 'now-60d',  to: 'now',      display: 'Last 60 days',          section: 3 },
  { from: 'now-90d',  to: 'now',      display: 'Last 90 days',          section: 3 },
  { from: 'now-6M',   to: 'now',      display: 'Last 6 months',         section: 3 },
  { from: 'now-1y',   to: 'now',      display: 'Last 1 year',           section: 3 },
  { from: 'now-2y',   to: 'now',      display: 'Last 2 years',          section: 3 },
  { from: 'now-5y',   to: 'now',      display: 'Last 5 years',          section: 3 },
];

var rangeIndex = {};
_.each(rangeOptions, function (frame) {
  rangeIndex[frame.from + ' to ' + frame.to] = frame;
});

  function getRelativeTimesList(timepickerSettings) {
    return _.map(timepickerSettings.time_options, function(duration: string) {
      return describeTextRange(duration);
    });
  }

  // handles expressions like
  // 5m
  // 5m to now/d
  // now/d to now
  // now/d
  // if no to <expr> then to now is assumed
  function describeTextRange(expr: string) {
    let rangeExpr = 'now-' + expr + ' to now';
    if (expr.indexOf('now') === 0) {
      rangeExpr = expr + ' to now';
    }

    let opt = rangeIndex[rangeExpr];
    if (opt) {
      return opt;
    }

    opt = {from: 'now-' + expr, to: 'now', display: 'Parse error'};

    if (/^\d+\w$/.test(expr)) {
      let unit = expr[expr.length - 1];
      let amount = parseInt(expr.substring(0, expr.length - 1));
      let span = spans[unit];
      if (span) {
        opt.display = 'Last ' + amount + ' ' + span.display;
        if (amount > 1) {
          opt.display += 's';
        }
      }
    }

    return opt;
  }

  function describeTimeRange(range) {
    var option = rangeIndex[range.from.toString() + ' to ' + range.to.toString()];
    if (option) {
      return option.display;
    }
    return "NA";
  }

export = {
  getRelativeTimesList: getRelativeTimesList,
  describeTextRange: describeTextRange,
  describeTimeRange: describeTimeRange,
}