/**
   This file contains the client-side implementation of fossil's /chat
   application. 
*/
window.fossil.onPageLoad(function(){
  const F = window.fossil, D = F.dom;
  const E1 = function(selector){
    const e = document.querySelector(selector);
    if(!e) throw new Error("missing required DOM element: "+selector);
    return e;
  };
  /**

        document.querySelector('body > div.header'),
        document.querySelector('body > div.mainmenu'),
        document.querySelector('body > #hbdrop'),
        document.querySelector('body > div.footer')
      ];
      f.contentArea = E1('div.content');
    }

    const resized = function(){
      const wh = window.innerHeight,
            com = document.body.classList.contains('chat-only-mode');
      var ht;
      var extra = 0;
      if(com){
        ht = wh;
      }else{
        f.elemsToCount.forEach((e)=>e ? extra += D.effectiveHeight(e) : false);
        ht = wh - extra;

    cs.e.btnClearFilter.addEventListener('click',function(){
      D.addClass(this,'hidden');
      cs.clearFilters();
    }, false);
    return cs;
  })()/*Chat initialization*/;

  /**
     An experiment in history navigation: when a message numref is
     clicked, we push the origin message onto the history and
     set up the back button to return to that message.
  */
  if(0) window.onpopstate = function(event){
    console.debug("onpopstate event",event.state, event);
    if(event.state && event.state.msgId){
      const e = Chat.setCurrentView(Chat.e.viewMessages).
            querySelector('.message-widget[data-msgid="'+event.state.msgId+'"]');
      console.debug("Popping history back to",event.state, e);
      if(e){
        Chat.MessageWidget.scrollToMessageElem(e);
        //F.page.setPageTitle("Fossil Chat #"+event.state.msgId);
        return;
      }
    }
    Chat.scrollMessagesTo(1);
  };

  const findParentWithClass = function(e, className){
    while(e && !e.classList.contains(className)){
      e = e.parentNode;
    }
    return e;
  };
  
  /** To be passed each MessageWidget's top-level DOM element
      after initial processing of the message, to set up
      hashtag references. */
  const setupHashtags = function f(elem){
    if(!f.$click){
      f.$click = function(ev){
        /* Click handler for hashtags */

        const tag = ev.target.dataset.numtag;
        if(tag){
          const e = Chat.e.viewMessages.querySelector(
            '.message-widget[data-msgid="'+tag+'"]'
          );
          if(e){
            Chat.MessageWidget.scrollToMessageElem(e);
            //Set up window.history() state...
            const p = 1 ? false : findParentWithClass(ev.target, 'message-widget');
            if(p){
              const state = {msgId: p.dataset.msgid};
              console.debug("Pushing history for msgid", state);
              const rc = window.history.pushState(state, "?");
              console.debug("History length =",window.history.length, rc);
            }
          }else{
            F.toast.warning("Message #"+tag+" not found in loaded messages.");
          }
        }
      };
    }
    elem.querySelectorAll('[data-hashtag]').forEach(function(e){

    /** Assumes that e is a MessageWidget element, ensures that
        Chat.e.viewMessages is visible, scrolls the message,
        and animates it a bit to make it more visible. */
    cf.scrollToMessageElem = function(e){
      if(e.firstElementChild){
        Chat.setCurrentView(Chat.e.viewMessages);
        e.scrollIntoView(false);
        Chat.animate(e, 'anim-fade-out-in');
      }
    };
    return cf;
  })()/*MessageWidget*/;

  const BlobXferState = (function(){/*drag/drop bits...*/
    /* State for paste and drag/drop */

    document.querySelectorAll('#chat-edit-buttons button').forEach(function(e){
      e.addEventListener('click',flip, false);
    });
  }
  setTimeout( ()=>Chat.inputFocus(), 0 );
  Chat.animate.$disabled = false;
  F.page.chat = Chat/* enables testing the APIs via the dev tools */;
});