(function() {
  if (window.WeReadApi) { return; }

  function bridge() {
    return window.RDEpubReaderBridge || null;
  }

  function sharedThemeCSS(theme) {
    if (!theme) { return ''; }
    var backgroundColor = theme.backgroundColor || 'transparent';
    var textColor = theme.textColor || 'inherit';
    return [
      ':root {',
      '  color-scheme: light;',
      '}',
      'html, body {',
      '  background: ' + backgroundColor + ' !important;',
      '  color: ' + textColor + ' !important;',
      '}',
      'a {',
      '  -webkit-tap-highlight-color: transparent;',
      '}'
    ].join('\n');
  }

  window.WeReadApi = {
    applySharedTheme: function(theme) {
      var css = sharedThemeCSS(theme);
      if (window.RDInjectedCSS) {
        window.RDInjectedCSS.setStyle('ss-reader-theme', css, {
          includeFrames: !!(theme && theme.includeFrames)
        });
      }
      return true;
    },
    applyPagination: function(styleText) {
      return !!(bridge() && bridge().applyPagination(styleText));
    },
    setPageMetrics: function(pageCount, pageStride) {
      return !!(bridge() && bridge().setPageMetrics(pageCount, pageStride));
    },
    scrollToPage: function(pageIndex) {
      return !!(bridge() && bridge().scrollToPage(pageIndex));
    },
    scrollToLocation: function(location, fallbackPageIndex) {
      return !!(bridge() && bridge().scrollToLocation(location, fallbackPageIndex));
    },
    setHighlights: function(items) {
      return !!(bridge() && bridge().setHighlights(items));
    },
    clearHighlights: function() {
      return !!(bridge() && bridge().clearHighlights());
    },
    setSearchPresentation: function(payload) {
      return !!(bridge() && bridge().setSearchPresentation(payload));
    },
    resolveDecorations: function() {
      return bridge() ? bridge().resolveDecorations() : { highlights: [], search: [] };
    },
    reportProgression: function(fragment) {
      return !!(bridge() && bridge().reportProgression(fragment));
    },
    selectionPayload: function() {
      return bridge() ? bridge().selectionPayload() : null;
    }
  };
})();