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// TODO: proper backwards search - implement our own component?
//     : implement our own highlighter?
//     : frameset pages
//     : <ESC> should cancel search highlighting in 'incsearch' mode and jump
//       back to the presearch page location - can probably use the same
//       solution as marks
//     : 'linksearch' searches should highlight link matches only
//     : changing any search settings should also update the search state including highlighting
//     : incremental searches shouldn't permanently update search modifiers

// make sure you only create this object when the "liberator" object is ready
function Search() //{{{
{
    ////////////////////////////////////////////////////////////////////////////////
    ////////////////////// PRIVATE SECTION /////////////////////////////////////////
    /////////////////////////////////////////////////////////////////////////////{{{

    // FIXME:
    //var self = this;               // needed for callbacks since "this" is the "liberator" object in a callback
    var found = false;               // true if the last search was successful
    var backwards = false;           // currently searching backwards
    var searchString = "";           // current search string (without modifiers)
    var searchPattern = "";          // current search string (includes modifiers)
    var lastSearchPattern = "";      // the last searched pattern (includes modifiers)
    var lastSearchString = "";       // the last searched string (without modifiers)
    var lastSearchBackwards = false; // like "backwards", but for the last search, so if you cancel a search with <esc> this is not set
    var caseSensitive = false;       // search string is case sensitive
    var linksOnly = false;           // search is limited to link text only

    // Event handlers for search - closure is needed
    liberator.registerCallback("change", modes.SEARCH_FORWARD, function (command) { search.searchKeyPressed(command); });
    liberator.registerCallback("submit", modes.SEARCH_FORWARD, function (command) { search.searchSubmitted(command); });
    liberator.registerCallback("cancel", modes.SEARCH_FORWARD, function () { search.searchCanceled(); });
    // TODO: allow advanced myModes in register/triggerCallback
    liberator.registerCallback("change", modes.SEARCH_BACKWARD, function (command) { search.searchKeyPressed(command); });
    liberator.registerCallback("submit", modes.SEARCH_BACKWARD, function (command) { search.searchSubmitted(command); });
    liberator.registerCallback("cancel", modes.SEARCH_BACKWARD, function () { search.searchCanceled(); });

    // set searchString, searchPattern, caseSensitive, linksOnly
    function processUserPattern(pattern)
    {
        //// strip off pattern terminator and offset
        //if (backwards)
        //    pattern = pattern.replace(/\?.*/, "");
        //else
        //    pattern = pattern.replace(/\/.*/, "");

        searchPattern = pattern;

        // links only search - \l wins if both modifiers specified
        if (/\\l/.test(pattern))
            linksOnly = true;
        else if (/\L/.test(pattern))
            linksOnly = false;
        else if (options["linksearch"])
            linksOnly = true;
        else
            linksOnly = false;

        // strip links-only modifiers
        pattern = pattern.replace(/(\\)?\\[lL]/g, function ($0, $1) { return $1 ? $0 : ""; });

        // case sensitivity - \c wins if both modifiers specified
        if (/\c/.test(pattern))
            caseSensitive = false;
        else if (/\C/.test(pattern))
            caseSensitive = true;
        else if (options["ignorecase"] && options["smartcase"] && /[A-Z]/.test(pattern))
            caseSensitive = true;
        else if (options["ignorecase"])
            caseSensitive = false;
        else
            caseSensitive = true;

        // strip case-sensitive modifiers
        pattern = pattern.replace(/(\\)?\\[cC]/g, function ($0, $1) { return $1 ? $0 : ""; });

        // remove any modifer escape \
        pattern = pattern.replace(/\\(\\[cClL])/g, "$1");

        searchString = pattern;
    }

    /* Stolen from toolkit.jar in Firefox, for the time being. The private
     * methods were unstable, and changed. The new version is not remotely
     * compatible with what we do.
     *   The following only applies to this object, and may not be
     * necessary, or accurate, but, just in case:
     *   The Original Code is mozilla.org viewsource frontend.
     *
     *   The Initial Developer of the Original Code is
     *   Netscape Communications Corporation.
     *   Portions created by the Initial Developer are Copyright (C) 2003
     *   the Initial Developer. All Rights Reserved.
     *
     *   Contributor(s):
     *       Blake Ross <blake@cs.stanford.edu> (Original Author)
     *       Masayuki Nakano <masayuki@d-toybox.com>
     *       Ben Basson <contact@cusser.net>
     *       Jason Barnabe <jason_barnabe@fastmail.fm>
     *       Asaf Romano <mano@mozilla.com>
     *       Ehsan Akhgari <ehsan.akhgari@gmail.com>
     *       Graeme McCutcheon <graememcc_firefox@graeme-online.co.uk>
     */
    var highlightObj = {
        search: function (aWord, matchCase)
        {
            var finder = Components.classes["@mozilla.org/embedcomp/rangefind;1"]
                                   .createInstance()
                                   .QueryInterface(Components.interfaces.nsIFind);
            if (matchCase !== undefined)
                finder.caseSensitive = matchCase;

            var range;
            while ((range = finder.Find(aWord,
                                        this.searchRange,
                                        this.startPt,
                                        this.endPt)))
                yield range;
        },

        highlightDoc: function highlightDoc(win, aWord)
        {
            Array.forEach(win.frames, function (frame) highlightObj.highlightDoc(frame, aWord));

            var doc = win.document;
            if (!doc || !(doc instanceof HTMLDocument))
                return;

            if (!aWord)
            {
                let elems = highlightObj.getSpans(doc);
                for (let i = elems.snapshotLength; --i >= 0;)
                {
                    let elem = elems.snapshotItem(i);
                    let docfrag = doc.createDocumentFragment();
                    let next = elem.nextSibling;
                    let parent = elem.parentNode;

                    let child;
                    while (child = elem.firstChild)
                        docfrag.appendChild(child);

                    parent.removeChild(elem);
                    parent.insertBefore(docfrag, next);
                    parent.normalize();
                }
                return;
            }

            var baseNode = <span highlight="Search"/>
            baseNode = util.xmlToDom(baseNode, window.content.document);

            var body = doc.body;
            var count = body.childNodes.length;
            this.searchRange = doc.createRange();
            this.startPt = doc.createRange();
            this.endPt = doc.createRange();

            this.searchRange.setStart(body, 0);
            this.searchRange.setEnd(body, count);

            this.startPt.setStart(body, 0);
            this.startPt.setEnd(body, 0);
            this.endPt.setStart(body, count);
            this.endPt.setEnd(body, count);

            liberator.interrupted = false;
            let n = 0;
            for (let retRange in this.search(aWord, caseSensitive))
            {
                // Highlight
                var nodeSurround = baseNode.cloneNode(true);
                var node = this.highlight(retRange, nodeSurround);
                this.startPt = node.ownerDocument.createRange();
                this.startPt.setStart(node, node.childNodes.length);
                this.startPt.setEnd(node, node.childNodes.length);
                if (n++ % 20 == 0)
                    liberator.threadYield(true);
                if (liberator.interrupted)
                    break;
            }
        },

        highlight: function highlight(aRange, aNode)
        {
            var startContainer = aRange.startContainer;
            var startOffset = aRange.startOffset;
            var endOffset = aRange.endOffset;
            var docfrag = aRange.extractContents();
            var before = startContainer.splitText(startOffset);
            var parent = before.parentNode;
            aNode.appendChild(docfrag);
            parent.insertBefore(aNode, before);
            return aNode;
        },

        getSpans: function (doc) buffer.evaluateXPath("//*[@liberator:highlight='Search']", doc)
    };

    /////////////////////////////////////////////////////////////////////////////}}}
    ////////////////////// OPTIONS /////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////////////////{{{

    options.add(["hlsearch", "hls"],
        "Highlight previous search pattern matches",
        "boolean", "false",
        {
            setter: function (value)
            {
                if (value)
                    search.highlight();
                else
                    search.clear();

                return value;
            }
        });

    options.add(["ignorecase", "ic"],
        "Ignore case in search patterns",
        "boolean", true);

    options.add(["incsearch", "is"],
        "Show where the search pattern matches as it is typed",
        "boolean", true);

    options.add(["linksearch", "lks"],
        "Limit the search to hyperlink text",
        "boolean", false);

    options.add(["smartcase", "scs"],
        "Override the 'ignorecase' option if the pattern contains uppercase characters",
        "boolean", true);

    /////////////////////////////////////////////////////////////////////////////}}}
    ////////////////////// MAPPINGS ////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////////////////{{{

    var myModes = config.browserModes;
    myModes = myModes.concat([modes.CARET]);

    mappings.add(myModes,
        ["/"], "Search forward for a pattern",
        function () { search.openSearchDialog(modes.SEARCH_FORWARD); });

    mappings.add(myModes,
        ["?"], "Search backwards for a pattern",
        function () { search.openSearchDialog(modes.SEARCH_BACKWARD); });

    mappings.add(myModes,
        ["n"], "Find next",
        function () { search.findAgain(false); });

    mappings.add(myModes,
        ["N"], "Find previous",
        function () { search.findAgain(true); });

    mappings.add(myModes.concat([modes.CARET, modes.TEXTAREA]), ["*"],
        "Find word under cursor",
        function ()
        {
            search.searchSubmitted(buffer.getCurrentWord(), false);
            search.findAgain();
        });

    mappings.add(myModes.concat([modes.CARET, modes.TEXTAREA]), ["#"],
        "Find word under cursor backwards",
        function ()
        {
            search.searchSubmitted(buffer.getCurrentWord(), true);
            search.findAgain();
        });

    /////////////////////////////////////////////////////////////////////////////}}}
    ////////////////////// COMMANDS ////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////////////////{{{

    commands.add(["noh[lsearch]"],
        "Remove the search highlighting",
        function () { search.clear(); },
        { argCount: "0" });

    /////////////////////////////////////////////////////////////////////////////}}}
    ////////////////////// PUBLIC SECTION //////////////////////////////////////////
    /////////////////////////////////////////////////////////////////////////////{{{

    return {

        // Called when the search dialog is asked for
        // If you omit "mode", it will default to forward searching
        openSearchDialog: function (mode)
        {
            if (mode == modes.SEARCH_BACKWARD)
            {
                commandline.open("?", "", modes.SEARCH_BACKWARD);
                backwards = true;
            }
            else
            {
                commandline.open("/", "", modes.SEARCH_FORWARD);
                backwards = false;
            }

            // TODO: focus the top of the currently visible screen
        },

        // Finds text in a page
        // TODO: backwards seems impossible i fear :(
        find: function (str, backwards)
        {
            let fastFind = getBrowser().fastFind;

            processUserPattern(str);

            fastFind.caseSensitive = caseSensitive;
            found = fastFind.find(searchString, linksOnly) != Components.interfaces.nsITypeAheadFind.FIND_NOTFOUND;

            if (!found)
                setTimeout(function () commandline.error = "E486: Pattern not found: " + searchPattern, 0);

            return found;
        },

        // Called when the current search needs to be repeated
        findAgain: function (reverse)
        {
            // this hack is needed to make n/N work with the correct string, if
            // we typed /foo<esc> after the original search.  Since searchString is
            // readonly we have to call find() again to update it.
            if (getBrowser().fastFind.searchString != lastSearchString)
                this.find(lastSearchString, false);

            let up = reverse ? !lastSearchBackwards : lastSearchBackwards;
            let result = getBrowser().fastFind.findAgain(up, linksOnly);

            if (result == Components.interfaces.nsITypeAheadFind.FIND_NOTFOUND)
            {
                commandline.error = "E486: Pattern not found: " + lastSearchPattern;
            }
            else if (result == Components.interfaces.nsITypeAheadFind.FIND_WRAPPED)
            {
                // hack needed, because wrapping causes a "scroll" event which clears
                // our command line
                setTimeout(function () {
                    if (up)
                        commandline.echo("search hit TOP, continuing at BOTTOM",
                            commandline.HL_WARNINGMSG, commandline.APPEND_TO_MESSAGES | commandline.FORCE_SINGLELINE);
                    else
                        commandline.echo("search hit BOTTOM, continuing at TOP",
                            commandline.HL_WARNINGMSG, commandline.APPEND_TO_MESSAGES | commandline.FORCE_SINGLELINE);
                }, 0);
            }
            else
            {
                commandline.status = (up ? "?" : "/") + lastSearchPattern;

                if (options["hlsearch"])
                    this.highlight(lastSearchString);
            }
        },

        // Called when the user types a key in the search dialog. Triggers a find attempt if 'incsearch' is set
        searchKeyPressed: function (command)
        {
            if (options["incsearch"])
                this.find(command, backwards);
        },

        // Called when the enter key is pressed to trigger a search
        // use forcedBackward if you call this function directly
        searchSubmitted: function (command, forcedBackward)
        {
            if (typeof forcedBackward === "boolean")
                backwards = forcedBackward;

            // use the last pattern if none specified
            if (!command)
                command = lastSearchPattern;

            if (!options["incsearch"] || !found)
            {
                this.clear();
                this.find(command, backwards);
            }

            lastSearchBackwards = backwards;
            //lastSearchPattern = command.replace(backwards ? /\?.*/ : /\/.*/, ""); // XXX
            lastSearchPattern = command;
            lastSearchString = searchString;

            // TODO: move to find() when reverse incremental searching is kludged in
            // need to find again for reverse searching
            if (backwards)
                setTimeout(function () { search.findAgain(false); }, 0);

            if (options["hlsearch"])
                this.highlight(searchString);

            modes.reset();
        },

        // Called when the search is canceled - for example if someone presses
        // escape while typing a search
        searchCanceled: function ()
        {
            this.clear();
            // TODO: code to reposition the document to the place before search started
        },

        // FIXME: thunderbird incompatible
        // this is not dependent on the value of 'hlsearch'
        highlight: function (text)
        {
            if (config.name == "Muttator")
                return;

            // already highlighted?
            if (highlightObj.getSpans(content.document).snapshotLength > 0)
                return;

            if (!text)
                text = lastSearchString;

            highlightObj.highlightDoc(window.content, text);

            // recreate selection since _highlightDoc collapses the selection backwards
            getBrowser().fastFind.findAgain(false, linksOnly);

            // TODO: remove highlighting from non-link matches (HTML - A/AREA with href attribute; XML - Xlink [type="simple"])
        },

        clear: function ()
        {
            highlightObj.highlightDoc(window.content);
            // need to manually collapse the selection if the document is not
            // highlighted
            getBrowser().fastFind.collapseSelection();
        }

    };
    //}}}
}; //}}}

// vim: set fdm=marker sw=4 ts=4 et: