/**
 * ABC Tier Scoring Engine
 */
(function () {
  'use strict';

  var App = window.BenchmarkApp;

  /**
   * Find sub-tier index for a given value against an industry threshold array.
   * The first threshold the value meets or exceeds → that index.
   */
  function findSubTierIndex(value, thresholdArray) {
    for (var i = 0; i < thresholdArray.length; i++) {
      if (value >= thresholdArray[i]) return i;
    }
    return thresholdArray.length - 1;
  }

  function indexToScore(index) {
    if (index <= 2) return 3; // A+, A, A-
    if (index <= 5) return 2; // B+, B, B-
    return 1;                 // C+, C, C-
  }

  function indexToTierLetter(index) {
    if (index <= 2) return 'A';
    if (index <= 5) return 'B';
    return 'C';
  }

  /**
   * Calculate ABC tier scoring for parsed params.
   * @param {Object} params — parsed params from params.js
   * @returns {Object} scoring result
   */
  App.calculateScoring = function (params) {
    var industry = params.industry;
    var thresholds = App.THRESHOLDS[industry];
    var labels = thresholds.labels;

    // Convert slugs to numeric values
    var values = {
      revenue: App.REVENUE_MAP[params.revenue],
      budget:  App.BUDGET_MAP[params.budget],
      asins:   params.asins,
      growth:  App.GROWTH_MAP[params.growth]
    };

    // Score each metric
    var metrics = {};
    var metricNames = ['revenue', 'budget', 'asins', 'growth'];

    for (var i = 0; i < metricNames.length; i++) {
      var name = metricNames[i];
      var idx = findSubTierIndex(values[name], thresholds[name]);
      metrics[name] = {
        value: values[name],
        subTierIndex: idx,
        subTier: labels[idx],
        tierLetter: indexToTierLetter(idx),
        score: indexToScore(idx)
      };
    }

    // Weighted score
    var weightedScore =
      metrics.revenue.score * 0.40 +
      metrics.budget.score  * 0.35 +
      metrics.asins.score   * 0.15 +
      metrics.growth.score  * 0.10;

    // Final tier
    var tier;
    if (weightedScore >= 2.5) tier = 'A';
    else if (weightedScore >= 1.7) tier = 'B';
    else tier = 'C';

    // Sub-tier from revenue for "YOU" marker position
    var subTier = metrics.revenue.subTier;

    return {
      tier: tier,
      subTier: subTier,
      subTierIndex: metrics.revenue.subTierIndex,
      weightedScore: Math.round(weightedScore * 100) / 100,
      metrics: metrics
    };
  };
})();