// Released under the MIT/X11 license
// http://www.opensource.org/licenses/mit-license.php

/**
 * returns content of the system clipboard
 * @return string with the content of the clipboard or "" if empty.
 * originally from
 * https://developer.mozilla.org/en/Using_the_Clipboard
 *
 */
// TODO to-be-replaced by
// var contents = jetpack.clipboard.get();
// http://hsivonen.iki.fi/kesakoodi/clipboard/
// https://wiki.mozilla.org/Labs/Jetpack/JEP/10

function getClipboard() {
   var clip = Cc["@mozilla.org/widget/clipboard;1"].
       getService(Ci.nsIClipboard);
   if (!clip) {
        throw new Error("No access to the clipboard!");
    }
   return clip;
}

function createTransferable() {
   var trans = Cc["@mozilla.org/widget/transferable;1"].
    createInstance(Ci.nsITransferable);
   if (!trans) {
    throw new Error("No access to the transfer object during the set of clipboard!");
   }
   return trans;
}

var getMethod = exports.get = function getMethod( flavor ) {
    var pastetext = "", mimeType = "", stuff = {};
    var len = 0, clipId = 0, clip = {}, trans = {};

    // flavor argument is optional
    if (flavor === undefined) {
        flavor = "plain";
    }
    
    if (flavor === "plain") {
        mimeType = "text/unicode";
    } else if (favor === "html") {
        mimeType = "text/html";
    } else {
        throw new Error("Unsupported flavor '" + flavor + "'!");
    }

    clip = getClipboard();
    
    trans = createTransferable();

    trans.addDataFlavor(mimeType);
    clip.getData(trans, clip.kGlobalClipboard);

    var str       = {};
    var strLength = {};

    trans.getTransferData(mimeType, str, strLength);

    if (str) {
        str = str.value.QueryInterface(Ci.nsISupportsString);
        pastetext = str.data.substring(0, strLength.value / 2);
    }
    return pastetext;
};

var setMethod = exports.set = function setMethod(content, flavor) {
    var mimeType = "", stuff = {};
    var len = 0, clipId = 0, clip = {}, trans = {};
    
    // flavor argument is optional
    if (flavor === undefined) {
        flavor = "plain";
    }
    
    if (flavor === "plain") {
        mimeType = "text/unicode";
    } else if (favor === "html") {
        mimeType = "text/html";
    } else {
        throw new Error("Unsupported flavor '" + flavor + "'!");
    }

    stuff = Cc["@mozilla.org/supports-string;1"].  
        createInstance(Ci.nsISupportsString);
    if (!stuff) {
        return false;
    }  
    stuff.data = content;
    len = content.length * 2;  

    clip = getClipboard();
    
    trans = createTransferable();

    trans.addDataFlavor(mimeType);
    trans.setTransferData(mimeType, stuff, content.length * 2);
    
    clip.setData(trans, null, clip.kGlobalClipboard);
    return true;
};

function createSupportsWString() {
    return Cc["@mozilla.org/supports-wstring;1"].
        createInstance(Ci.nsISupportsWString);
}

var flavorsMethod = exports.getCurrentFlavors = function flavorsMethod() {
    // currently the only possible flavors in Jetpack-prototype are "plain" and
    // "html", i.e., "text/plain" (or text/unicode?) and "text/html" (or
    // application/xml+xhtml?)
    var possibleTypes = {
        "text/unicode": "plain",
        "text/plain": "plain",
        "text/html": "html"
    };
    var flavourArray = [];

    for (mime in possibleTypes) {
        var kSuppString = createSupportsWString();
        kSuppString.data = mime;
        // FIXME Missing some kind of if (mime in flavors) ...
        flavourArray.add(possibleTypes[mime]);
    }
    return flavourArray;
};