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/**
* Allows for one click modification of section headings when viewing a page
* add the following line to your .js file to use it:
  importScript( 'User:The Evil IP address/hdedit.js' ); // Backlink: [[User:The Evil IP address/hdedit.js]]
* @author Janko Hoener (The Evil IP address)
* @version 1.1.1
*/
mw.loader.load('mediawiki.api');
window.hdedit = {
	
    openeditform: function ($e) {
        hdedit.anchor = $e.attr('id');
        hdedit.pagename = mw.config.get('wgPageName');
        hdedit.api = new mw.Api();
        hdedit.api.get( {
                action: 'parse',
                page: this.pagename,
                prop: 'sections',
                format: 'json'
        }).done( function (data) {
        	error = false;
        	error_msg = '';
            $.each(data.parse.sections, function (i, v) {
                    if (v.anchor == hdedit.anchor) {
                    	if (v.index !== '') {
                        	hdedit.index = v.index;
                    	}
                    	else {
                    		error = true;
                    		error_msg = 'This section cannot be edited automatically '  
                    		'because it uses HTML formatting.';
                    	}
                        if (v.fromtitle && (v.fromtitle != hdedit.pagename)) {
                        	error = true;
                        	error_msg  = 'This section cannot be edited automatically '  
                        	'because it is transcluded from a template.';
                        }
                        return false;
                    }
            });
            if (error) {
            	hdedit.seterror(error_msg);
            	return;
            }
            if (hdedit.$e) {
            	hdedit.cancel();
        	}
        	hdedit.$e = $e;
            hdedit.api.get({
                    action: 'parse',
                    page: hdedit.pagename,
                    section: hdedit.index,
                    prop: 'wikitext',
                    format: 'json'
            }).done( function (obj) {
                hdedit.wikitext = obj.parse.wikitext['*'];
                hdedit.section_wikitext = hdedit.wikitext.replace(/^(= )\s*(. ?)\s*\1[\s\S]*$/, '$2');
                hdedit.inputsize = hdedit.section_wikitext.length*1.5;
                var form = $('<form>').css('display', 'inline').submit(hdedit.save);
                var input = $('<input>').attr('id', 'hdedit_input').attr('size', hdedit.inputsize).val(hdedit.section_wikitext);
                var button1 = $('<button>').attr('id', 'hdedit_submit').attr('type', 'submit').text('Save');
                var button2 = $('<button>').attr('type', 'button').attr('id', 'hdedit_cancel').text('Cancel').click(hdedit.cancel);
                $(form).append(input).append(button1).append(button2);
                hdedit.form = form;
                $e.after(form);
                $e.hide();
            }
            );
        }
        );
    },
    
    save: function () {
        hdedit.newheading = $(this).parent().find('input').val();
        if (hdedit.newheading == hdedit.section_wikitext) {
            return false;
        }
        $('#hdedit_input, #hdedit_submit, #hdedit_cancel').attr('disabled', 'disabled');
        hdedit.api.edit(hdedit.pagename, function () {
        		return {
        			action: 'edit',
        			format: 'json',
        			section: hdedit.index,
        			minor: true,
        			summary: 'Section heading change: '   hdedit.section_wikitext   ' → '   hdedit.newheading 
        			  ' using a [[User:The Evil IP address/hdedit|script]]',
        			text: hdedit.wikitext.replace(/^(= )(\s*). ?(\s*)\1(\s*)$/m, '$1$2'   hdedit.newheading 
        				  '$3$1$4'),
        		};
        }).then(
        function (resp) {
        	if (resp.result == 'Success') {
        		window.location.reload();
        	}
        	else if (resp.result == 'Failure') {
        		hdedit.seterror('API returned error code '   data.error.code   ': '   data.error.info);
        	}
        	else {
        		hdedit.seterror('Unknown API error.');
        	}
        });
        return false;
    },
    
    cancel: function () {
        hdedit.$e.show();
        hdedit.form.remove();
    },
    
    seterror: function (msg) { 
    	mw.notify(msg   '\nPlease edit the section heading manually.', {title: 'Error!', autoHide: false});
    },
    
    getpref: function (name) {
    	if (window.hdedit_prefs !== undefined && name in window.hdedit_prefs) {
    		return window.hdedit_prefs[name];
    	}
    	else {
    		return hdedit.defaultprefs[name];
    	}
    },
    
    defaultprefs: {
        'eventToActivate': 'click'
    },
    
};

if (mw.config.get('wgNamespaceNumber') >= 0              // disable on special pages
    && mw.config.get('wgAction') == 'view'               // activate on view only
    && mw.config.get('wgIsProbablyEditable')             // only if the page is probably editable
    && !mw.config.get('wgIsMainPage')                    // disable on Main Page
    && !('sysop' in mw.config.get('wgRestrictionEdit'))) { // disable on protected pages
    // they should be edited manually per https://en.wikipedia.org/w/index.php?oldid=982545683 

    var eventname = hdedit.getpref('eventToActivate');
    var selector = ''; // find the appropriate selector of headings after breaking change https://www.mediawiki.org/wiki/Heading_HTML_changes
    var oldmarkup = $('h1 span.mw-headline, h2 span.mw-headline, h3 span.mw-headline, h4 span.mw-headline, h5 span.mw-headline, h6 span.mw-headline'); // still using previous layout
    var newmarkup = $('#bodyContent h1, #bodyContent h2, #bodyContent h3, #bodyContent h4, #bodyContent h5, #bodyContent h6'); // using new layout, all h* elements of the page body
    if (oldmarkup.length) { // we have the old layout, then load only on those selectors
    	selector = oldmarkup;
    }
	else if (newmarkup.length) { // we have the new layout, then load only on those selectors
		selector = newmarkup;
	}
    $(selector).bind(eventname, 
	    function () {
		    hdedit.openeditform($(this));
	    }
    );
}