/*
 * tonalmine: per-user appearance (mode + color palette).
 *
 * Redmine loads this file in <head>, so the saved choice is applied before the page renders
 * (no flash of the default colors). The picker is added to the profile menu and the mobile
 * flyout. The choice is stored per browser in localStorage.
 */
(function () {
  // Ids must match PALETTES in tools/palettes/build_palettes.mjs (the build checks this).
  var PALETTES = [
    ['purple', 'Purple', '#6750A4'],
    ['blue', 'Blue', '#0061A4'],
    ['green', 'Green', '#386A20'],
    ['orange', 'Orange', '#8B5000']
  ];
  var MODES = [['auto', 'Auto'], ['light', 'Light'], ['dark', 'Dark']];
  var CONTRASTS = [['standard', 'Standard'], ['medium', 'Medium'], ['high', 'High']];
  var KEY = 'tonalmine';
  var CUSTOM_SEL = ':root[data-palette="custom"]';
  var root = document.documentElement;

  function load() {
    try { return JSON.parse(localStorage.getItem(KEY)) || {}; } catch (e) { return {}; }
  }

  function save(prefs) {
    try { localStorage.setItem(KEY, JSON.stringify(prefs)); } catch (e) { /* private mode: applies to this page only */ }
  }

  function apply(prefs) {
    if (prefs.palette && prefs.palette !== PALETTES[0][0]) root.setAttribute('data-palette', prefs.palette);
    else root.removeAttribute('data-palette');
    if (prefs.mode === 'light' || prefs.mode === 'dark') root.setAttribute('data-mode', prefs.mode);
    else root.removeAttribute('data-mode');
    if (prefs.contrast === 'medium' || prefs.contrast === 'high') root.setAttribute('data-contrast', prefs.contrast);
    else root.removeAttribute('data-contrast');
    // The custom palette's rules are generated once (see withScheme) and kept with the prefs.
    if (prefs.palette === 'custom' && prefs.css) {
      var style = document.getElementById('nm-custom-palette');
      if (!style) {
        style = document.createElement('style');
        style.id = 'nm-custom-palette';
        document.head.appendChild(style);
      }
      style.textContent = prefs.css;
    }
  }

  // The scheme generator (scheme.js, ~90 KB) is only loaded when someone picks a custom color.
  // Redmine serves theme assets under digested names only, so its URL comes from the CSS
  // variable --nm-scheme-js (Redmine rewrites url() in CSS to the digested path).
  var schemeScript;
  function withScheme(done) {
    if (window.tonalmineScheme) return done(window.tonalmineScheme);
    if (!schemeScript) {
      var url = getComputedStyle(root).getPropertyValue('--nm-scheme-js').match(/url\(["']?([^"')]+)/)[1];
      schemeScript = document.createElement('script');
      schemeScript.src = url;
      document.head.appendChild(schemeScript);
    }
    schemeScript.addEventListener('load', function () { done(window.tonalmineScheme); });
  }

  var prefs = load();
  apply(prefs);

  function button(attr, value, label, pressed, extra) {
    return '<button type="button" ' + attr + '="' + value + '" aria-pressed="' + pressed + '"' + (extra || '') + '>' + label + '</button>';
  }

  function pickerHtml() {
    var mode = prefs.mode || 'auto';
    var contrast = prefs.contrast || 'standard';
    var palette = prefs.palette || PALETTES[0][0];
    return '<div class="nm-appearance">' +
      '<div class="nm-appearance__title">Appearance</div>' +
      '<div class="nm-segmented" role="group" aria-label="Mode">' +
      MODES.map(function (m) { return button('data-nm-mode', m[0], m[1], m[0] === mode); }).join('') +
      '</div>' +
      '<div class="nm-appearance__title">Contrast</div>' +
      '<div class="nm-segmented" role="group" aria-label="Contrast">' +
      CONTRASTS.map(function (c) { return button('data-nm-contrast', c[0], c[1], c[0] === contrast); }).join('') +
      '</div>' +
      '<div class="nm-swatches" role="group" aria-label="Color">' +
      PALETTES.map(function (p) {
        return button('data-nm-palette', p[0], '', p[0] === palette,
          ' class="nm-swatch" title="' + p[1] + '" aria-label="' + p[1] + '" style="--nm-swatch: ' + p[2] + '"');
      }).join('') +
      '<label class="nm-swatch nm-swatch--custom" data-nm-palette="custom" aria-pressed="' + (palette === 'custom') + '"' +
      (prefs.seed ? ' style="--nm-swatch: ' + prefs.seed + '"' : '') + ' title="Custom color">' +
      '<input type="color" data-nm-custom value="' + (prefs.seed || PALETTES[0][2].toLowerCase()) + '" aria-label="Custom color"></label>' +
      '</div></div>';
  }

  function sync() {
    document.querySelectorAll('[data-nm-mode]').forEach(function (b) {
      b.setAttribute('aria-pressed', String(b.getAttribute('data-nm-mode') === (prefs.mode || 'auto')));
    });
    document.querySelectorAll('[data-nm-contrast]').forEach(function (b) {
      b.setAttribute('aria-pressed', String(b.getAttribute('data-nm-contrast') === (prefs.contrast || 'standard')));
    });
    document.querySelectorAll('[data-nm-palette]').forEach(function (b) {
      b.setAttribute('aria-pressed', String(b.getAttribute('data-nm-palette') === (prefs.palette || PALETTES[0][0])));
    });
  }

  document.addEventListener('click', function (event) {
    var target = event.target.closest('[data-nm-mode], [data-nm-contrast], [data-nm-palette]');
    if (!target) return;
    if (target.hasAttribute('data-nm-mode')) prefs.mode = target.getAttribute('data-nm-mode');
    else if (target.hasAttribute('data-nm-contrast')) prefs.contrast = target.getAttribute('data-nm-contrast');
    // The custom swatch opens the color dialog; it only selects the palette once a color was picked.
    else if (target.getAttribute('data-nm-palette') !== 'custom' || prefs.css) prefs.palette = target.getAttribute('data-nm-palette');
    save(prefs);
    apply(prefs);
    sync();
  });

  document.addEventListener('input', function (event) {
    if (!event.target.matches('[data-nm-custom]')) return;
    var seed = event.target.value;
    withScheme(function (scheme) {
      prefs.palette = 'custom';
      prefs.seed = seed;
      prefs.css = scheme.paletteCss(CUSTOM_SEL, seed);
      save(prefs);
      apply(prefs);
      sync();
      document.querySelectorAll('[data-nm-custom]').forEach(function (input) {
        input.value = seed;
        input.parentNode.style.setProperty('--nm-swatch', seed);
      });
    });
  });

  document.addEventListener('DOMContentLoaded', function () {
    var menu = document.querySelector('#account .dropdown-content .dropdown-divider');
    if (menu) menu.insertAdjacentHTML('afterend', pickerHtml() + '<div class="dropdown-divider"></div>');
    var flyout = document.querySelector('.js-flyout-menu');
    if (flyout) flyout.insertAdjacentHTML('beforeend', pickerHtml());
  });
})();