import 'codemirror/addon/mode/simple';
import {
    org_cycle, org_shifttab, org_metaleft, org_metaright, org_meta_return, org_metaup,
    org_metadown, org_insert_todo_heading, org_shiftleft, org_shiftright, fold, unfold,
    isFold, org_set_fold, org_shiftmetaleft, org_shiftmetaright
} from './emacs-org';
import { pathBuilder, dirname } from '../../../helpers/';
let CodeMirror = window.CodeMirror;

CodeMirror.__mode = 'orgmode';

CodeMirror.defineSimpleMode("orgmode", {
    start: [
        {regex: /^(\*\s)(TODO|DOING|WAITING|NEXT|PENDING|)(CANCELLED|CANCELED|CANCEL|DONE|REJECTED|STOP|STOPPED|)(\s+\[\#[A-C]\]\s+|)(.*?)(?:(\s{10,}|))(\:[\S]+\:|)$/, token: ["header level1 org-level-star","header level1 org-todo","header level1 org-done", "header level1 org-priority", "header level1", "header level1 void", "header level1 comment"]},
        {regex: /^(\*{1,}\s)(TODO|DOING|WAITING|NEXT|PENDING|)(CANCELLED|CANCELED|CANCEL|DEFERRED|DONE|REJECTED|STOP|STOPPED|)(\s+\[\#[A-C]\]\s+|)(.*?)(?:(\s{10,}|))(\:[\S]+\:|)$/, token: ["header org-level-star","header org-todo","header org-done", "header org-priority", "header", "header void", "header comment"]},
        {regex: /(\+[^\+]+\+)/, token: ["strikethrough"]},
        {regex: /(\*[^\*]+\*)/, token: ["strong"]},
        {regex: /(\/[^\/]+\/)/, token: ["em"]},
        {regex: /(\_[^\_]+\_)/, token: ["link"]},
        {regex: /(\~[^\~]+\~)/, token: ["comment"]},
        {regex: /(\=[^\=]+\=)/, token: ["comment"]},
        {regex: /\[\[[^\[\]]+\]\[[^\[\]]+\]\]/, token: "org-url"}, // links
        {regex: /\[\[[^\[\]]+\]\]/, token: "org-image"}, // image
        {regex: /\[[xX\s\-\_]\]/, token: 'qualifier org-toggle'}, // checkbox
        {regex: /\#\+BEGIN_[A-Z]*/, token: "comment", next: "env"}, // comments
        {regex: /:?[A-Z_]+\:.*/, token: "comment"}, // property drawers
        {regex: /(\#\+[a-zA-Z_]*)(\:.*)/, token: ["keyword", 'qualifier']}, // environments
        {regex: /(CLOCK\:|SHEDULED\:|DEADLINE\:)(\s.+)/, token: ["comment", "keyword"]}
    ],
    env: [
        {regex: /.*?\#\+END_[A-Z]*/, token: "comment", next: "start"},
        {regex: /.*/, token: "comment"}
    ]
});
CodeMirror.registerHelper("fold", "orgmode", function(cm, start) {
    // init
    const levelToMatch = headerLevel(start.line);

    // no folding needed
    if(levelToMatch === null) return;

    // find folding limits
    const lastLine = cm.lastLine();
    let end = start.line;
    while(end < lastLine){
        end += 1;
        let level = headerLevel(end);
        if(level && level <= levelToMatch) {
            end = end - 1;
            break;
        };
    }

    return {
        from: CodeMirror.Pos(start.line, cm.getLine(start.line).length),
        to: CodeMirror.Pos(end, cm.getLine(end).length)
    };

    function headerLevel(lineNo) {
        var line = cm.getLine(lineNo);
        var match = /^\*+/.exec(line);
        if(match && match.length === 1 && /header/.test(cm.getTokenTypeAt(CodeMirror.Pos(lineNo, 0)))){
            return match[0].length;
        }
        return null;
    }
});
CodeMirror.registerGlobalHelper("fold", "drawer", function(mode) {
    return mode.name === 'orgmode' ? true : false;
}, function(cm, start) {
    const drawer = isBeginningOfADrawer(start.line);
    if(drawer === false) return;

    // find folding limits
    const lastLine = cm.lastLine();
    let end = start.line;
    while(end < lastLine){
        end += 1;
        if(isEndOfADrawer(end)){
            break;
        }
    }

    return {
        from: CodeMirror.Pos(start.line, cm.getLine(start.line).length),
        to: CodeMirror.Pos(end, cm.getLine(end).length)
    };

    function isBeginningOfADrawer(lineNo) {
        var line = cm.getLine(lineNo);
        var match = /^\:.*\:$/.exec(line);
        if(match && match.length === 1 && match[0] !== ':END:'){
            return true;
        }
        return false;
    }
    function isEndOfADrawer(lineNo){
        var line = cm.getLine(lineNo);
        return line.trim() === ':END:' ? true : false;
    }
});


CodeMirror.registerHelper("orgmode", "init", (editor, fn) => {
    editor.setOption("extraKeys", {
        "Tab": function(cm) { org_cycle(cm); },
        "Shift-Tab": function(cm){ fn('shifttab', org_shifttab(cm)); },
        "Alt-Left": function(cm){ org_metaleft(cm); },
        "Alt-Right": function(cm){ org_metaright(cm); },
        "Alt-Enter": function(cm){ org_meta_return(cm); },
        "Alt-Up": function(cm){ org_metaup(cm); },
        "Alt-Down": function(cm){ org_metadown(cm); },
        "Shift-Alt-Left": function(cm){ org_shiftmetaleft(cm); },
        "Shift-Alt-Right": function(cm){ org_shiftmetaright(cm); },
        "Shift-Alt-Enter": function(cm){ org_insert_todo_heading(cm); },
        "Shift-Left": function(cm){ org_shiftleft(cm); },
        "Shift-Right": function(cm){ org_shiftright(cm); }
    });
    fn('shifttab', org_set_fold(editor));

    editor.on('mousedown', toggleHandler);
    editor.on('touchstart', toggleHandler);
    editor.on('gutterClick', foldLine);

    // fold everything except headers by default
    editor.operation(function() {
        for (var i = 0; i < editor.lineCount() ; i++) {
            if(/header/.test(editor.getTokenTypeAt(CodeMirror.Pos(i, 0))) === false){
                fold(editor, CodeMirror.Pos(i, 0));
            }
        }
    });
    return CodeMirror.orgmode.destroy.bind(this, editor);
});

CodeMirror.registerHelper("orgmode", "destroy", (editor) => {
    editor.off('mousedown', toggleHandler);
    editor.off('touchstart', toggleHandler);
    editor.off('gutterClick', foldLine);
});

function foldLine(cm, line){
    const cursor = {line: line, ch: 0};
    isFold(cm, cursor) ? unfold(cm, cursor) : fold(cm, cursor);
}


let widgets = [];
function toggleHandler(cm, e){
    const position = cm.coordsChar({
        left: e.clientX || (e.targetTouches && e.targetTouches[0].clientX),
        top: e.clientY || (e.targetTouches && e.targetTouches[0].clientY)
    }, "page"),
          token = cm.getTokenAt(position);

    _disableSelection();
    if(/org-level-star/.test(token.type)){
        _preventIfShould();
        _foldHeadline();
        _disableSelection();
    }else if(/org-toggle/.test(token.type)){
        _preventIfShould();
        _toggleCheckbox();
        _disableSelection();
    }else if(/org-todo/.test(token.type)){
        _preventIfShould();
        _toggleTodo();
        _disableSelection();
    }else if(/org-done/.test(token.type)){
        _preventIfShould();
        _toggleDone();
        _disableSelection();
    }else if(/org-priority/.test(token.type)){
        _preventIfShould();
        _togglePriority();
        _disableSelection();
    }else if(/org-url/.test(token.type)){
        _disableSelection();
        _navigateLink();
    }else if(/org-image/.test(token.type)){
        _disableSelection();
        _toggleImageWidget();
    }

    function _preventIfShould(){
        if('ontouchstart' in window) e.preventDefault();
    }
    function _disableSelection(){
        cm.on('beforeSelectionChange', _onSelectionChangeHandler);
        function _onSelectionChangeHandler(cm, obj){
            obj.update([{
                anchor: position,
                head: position
            }]);
            cm.off('beforeSelectionChange', _onSelectionChangeHandler);
        }
    }

    function _foldHeadline(){
        const line = position.line;
        if(line >= 0){
            const cursor = {line: line, ch: 0};
            isFold(cm, cursor) ? unfold(cm, cursor) : fold(cm, cursor);
        }
    }

    function _toggleCheckbox(){
        const line = position.line;
        const content = cm.getRange({line: line, ch: token.start}, {line: line, ch: token.end});
        let new_content = content === "[X]" || content === "[x]" ? "[ ]" : "[X]";
        cm.replaceRange(new_content, {line: line, ch: token.start}, {line: line, ch: token.end});
    }

    function _toggleTodo(){
        const line = position.line;
        cm.replaceRange("DONE", {line: line, ch: token.start}, {line: line, ch: token.end});
    }

    function _toggleDone(){
        const line = position.line;
        cm.replaceRange("TODO", {line: line, ch: token.start}, {line: line, ch: token.end});
    }

    function _togglePriority(){
        const PRIORITIES = [" [#A] ", " [#B] ", " [#C] ", " [#A] "];
        const line = position.line;
        const content = cm.getRange({line: line, ch: token.start}, {line: line, ch: token.end});
        let new_content = PRIORITIES[PRIORITIES.indexOf(content) + 1];
        cm.replaceRange(new_content, {line: line, ch: token.start}, {line: line, ch: token.end});
    }

    function _toggleImageWidget(){
        let exist = !!widgets
            .filter((line) => line === position.line)[0];

        if(exist === false){
            if(!token.string.match(/\[\[(.*)\]\]/)) return null;
            let $node = _buildImage(RegExp.$1);
            const widget = cm.addLineWidget(position.line, $node, {coverGutter: false});
            widgets.push(position.line);
            $node.addEventListener('click', closeWidget);

            function closeWidget(){
                widget.clear();
                $node.removeEventListener('click', closeWidget);
                widgets = widgets.filter((line) => line !== position.line);
            }
        }
        function _buildImage(src){
            let $el = document.createElement("div");
            let $img = document.createElement("img");

            if(/^https?\:\/\//.test(src)){
                $img.src = src;
            }else{
                const root_path = dirname(window.location.pathname.replace(/^\/view/, ''));
                const img_path = src;
                $img.src = "/api/files/cat?path="+encodeURIComponent(pathBuilder(root_path, img_path));
            }
            $el.appendChild($img);
            return $el;
        }
        return null;
    }

    function _navigateLink(){
        token.string.match(/\[\[(.*?)\]\[/);
        const link = RegExp.$1;
        if(!link) return;

        if(/^https?\:\/\//.test(link)){
            window.open(link);
        }else{
            const root_path = dirname(window.location.pathname.replace(/^\/view/, ''));
            const link_path = link;
            window.open("/view"+pathBuilder(root_path, link_path));
        }
    }
}


export default CodeMirror;