/* Adapted from 'nicetitles' at http://www.kryogenix.org/code/browser/nicetitle/ */

addEvent(window, "load", makeNiceTitles);

var XHTMLNS = "http://www.w3.org/1999/xhtml";
var CURRENT_NICE_TITLE;
var browser = new Browser();

function getDate (dir) {
    if (dir == "birth") {
        return "1983";
    }
    if (dir == "cat01") {
        return "May/June 1983";
    } if (dir == "cat02") {
        return "Mid 1983";
    } else if (dir == "catlast") {
        return "Late 1983";
    } else {
        // One-month gap at issue 94, so increment the issue number to make up for it
        if (dir >= 94) { dir++; }
        var month = dir % 12;
        var year = 1984  + ((dir - month) / 12);
        month = [ "January", "February", "March", "April", "May", "June", "July",
                  "August", "September", "October", "November", "December"] [month];
        return month + " " + year;
    }
}

function makeNiceTitles() {

    if (!document.createElement || !document.getElementsByTagName) return;
    // add namespace methods to HTML DOM; this makes the script work in both
    // HTML and XML contexts.
    if(!document.createElementNS)
    {
        document.createElementNS = function(ns,elt) {
            return document.createElement(elt);
        }
    }
    if( !document.links )
    {
        document.links = document.getElementsByTagName("a");
    }
    for (var ti=0;ti<document.links.length;ti++) {
        var lnk = document.links[ti];
        if (lnk.getAttribute("class") == "issue" || lnk.className == "issue" ||
            lnk.getAttribute("class") == "birth" || lnk.className == "birth") {
            lnk.setAttribute("nicetitle",lnk.title);
            lnk.removeAttribute("title");
            addEvent(lnk,"mouseover",showNiceTitle);
            addEvent(lnk,"mouseout",hideNiceTitle);
            addEvent(lnk,"focus",showNiceTitle);
            addEvent(lnk,"blur",hideNiceTitle);
        }
    }
}

function findPosition( oLink ) {
  if( oLink.offsetParent ) {
    for( var posX = 0, posY = 0; oLink.offsetParent; oLink = oLink.offsetParent ) {
      posX += oLink.offsetLeft;
      posY += oLink.offsetTop;
    }
    return [ posX, posY ];
  } else {
    return [ oLink.x, oLink.y ];
  }
}

function showNiceTitle(e) {
    if (CURRENT_NICE_TITLE) hideNiceTitle(CURRENT_NICE_TITLE);
    if (!document.getElementsByTagName) return;
    if (window.event && window.event.srcElement) {
        lnk = window.event.srcElement;
    } else if (e && e.target) {
        lnk = e.target;
    }
    if (!lnk) return;
    if (lnk.nodeType == 3) {
        // lnk is a textnode -- ascend parents until we hit a link
        lnk = getParent(lnk,"A");
    }
    if (!lnk) return;

    // Get the issue number from the link URL
    var issue = lnk.href;
    // Find the index of the last "/" (../index.htm) and
    // get rid of it and everything following
    if (issue.lastIndexOf("/") > -1) {
         issue = issue.substring (0, issue.lastIndexOf("/"));
        if (issue.lastIndexOf("/") > -1) {
             issue = issue.substring (1+issue.lastIndexOf("/"));
        }
    }
    var thumbnail = issue;
    // Cover thumbnail is crashxx.jpg unless this is a catalogue
    if (issue.indexOf ("cat") < 0) {
        thumbnail = "crash"+issue;
    }
    thumbnail = "thumbnails/covers/" + thumbnail + ".jpg";
    if (issue == "birth") {
        thumbnail = "birth/thumbnails/birth_1.jpg";
    }

    nicetitle = lnk.getAttribute("nicetitle");
    
    var d = document.createElementNS(XHTMLNS,"div");
    d.className = "nicetitle";

    month = document.createTextNode(getDate (issue));
    pmonth = document.createElementNS(XHTMLNS,"p");
    pmonth.className = "issue";
    pmonth.appendChild(month);
    d.appendChild(pmonth);

    img = document.createElementNS(XHTMLNS,"img");
    img.src = thumbnail;
    img.width=100;
    img.height=146;
    d.appendChild(img);

    tnt = document.createTextNode(nicetitle);
    pat = document.createElementNS(XHTMLNS,"p");
    pat.className = "titletext";
    pat.appendChild(tnt);
    d.appendChild(pat);

    STD_WIDTH = 120;
    w = STD_WIDTH;
    mpos = findPosition(lnk);
    mx = mpos[0];
    my = mpos[1];

    d.style.left = (mx+15) + 'px';
    d.style.top = (my+35) + 'px';
    if (window.innerWidth && ((mx+w) > window.innerWidth)) {
        d.style.left = (window.innerWidth - w - 25) + "px";
    }
    if (document.body.scrollWidth && ((mx+w) > document.body.scrollWidth)) {
        d.style.left = (document.body.scrollWidth - w - 25) + "px";
    }
    
    document.getElementsByTagName("body")[0].appendChild(d);
    
    CURRENT_NICE_TITLE = d;
}

function hideNiceTitle(e) {
    if (!document.getElementsByTagName) return;
    if (CURRENT_NICE_TITLE) {
        document.getElementsByTagName("body")[0].removeChild(CURRENT_NICE_TITLE);
        CURRENT_NICE_TITLE = null;
    }
}

// Add an eventListener to browsers that can do it somehow.
// Originally by the amazing Scott Andrew.
function addEvent(obj, evType, fn){
  if (obj.addEventListener){
    obj.addEventListener(evType, fn, false);
    return true;
  } else if (obj.attachEvent){
	var r = obj.attachEvent("on"+evType, fn);
    return r;
  } else {
	return false;
  }
}

function getParent(el, pTagName) {
	if (el == null) return null;
	else if (el.nodeType == 1 && el.tagName.toLowerCase() == pTagName.toLowerCase())	// Gecko bug, supposed to be uppercase
		return el;
	else
		return getParent(el.parentNode, pTagName);
}

function getMousePosition(event) {
  if (browser.isIE) {
    x = window.event.clientX + document.documentElement.scrollLeft
      + document.body.scrollLeft;
    y = window.event.clientY + document.documentElement.scrollTop
      + document.body.scrollTop;
  }
  if (browser.isNS) {
    x = event.clientX + window.scrollX;
    y = event.clientY + window.scrollY;
  }
  return [x,y];
}

// Determine browser and version.

function Browser() {
// blah, browser detect, but mouse-position stuff doesn't work any other way
  var ua, s, i;

  this.isIE    = false;
  this.isNS    = false;
  this.version = null;

  ua = navigator.userAgent;

  s = "MSIE";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isIE = true;
    this.version = parseFloat(ua.substr(i + s.length));
    return;
  }

  s = "Netscape6/";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isNS = true;
    this.version = parseFloat(ua.substr(i + s.length));
    return;
  }

  // Treat any other "Gecko" browser as NS 6.1.
  s = "Gecko";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isNS = true;
    this.version = 6.1;
    return;
  }
}