/* Replace external links to GeoHack with direct links to a single mapping provider.
 *
 * It support the following replacement variables found in GeoHack:
 * {latdegdec} {londegdec} {scale} {span} {osmzoom}
 *
 * Based on a script by ]: ]
 *
- Instructions: add the following two lines to your common.js (or skin-specific js):

importScript('User:Evad37/GeoHack_replacement_script.js'); // ]
ghrs_mapprovider = "<url>";

- <url> is the url to load, specifiying the replacement variables above instead of actual values
- These urls can be found at ]
- For example, Google Maps:
ghrs_mapprovider = "http://maps.google.com/maps?ll={latdegdec},{londegdec}&spn={span},{span}&q={latdegdec},{londegdec}";
- or for OpenStreetMap:
ghrs_mapprovider = "http://www.openstreetmap.org/index.html?mlat={latdegdec}&mlon={londegdec}&zoom={osmzoom}&layers=B000FTF";
*/ 
jQuery( function( $ ) {
	if (window === undefined) return;
 	var geohack_base = "//geohack.toolforge.org/geohack.php";
	var coord_filter = /params=(+)_(*)_?(*)_?()_(+)_(*)_?(*)_?()(*)/;
	var replaceLinks = function ( $content ) {
		var link, lat, lon, scale;
		$content.find("a").each(function() {
			console.log(" caption link href:", $(this).attr("href"));
			if(coord_filter.exec($(this).attr("href"))) {
				// latitude and longitude
				lat=(1.0*RegExp.$1) + ((RegExp.$2||0)/60.0) + ((RegExp.$3||0)/3600.0);
				if(RegExp.$4!='N') lat*=-1;
				lon=(1.0*RegExp.$5) + ((RegExp.$6||0)/60.0) + ((RegExp.$7||0)/3600.0);
				if(RegExp.$8=='W') lon*=-1;
				
				// Determine scale/zoom
				var params = RegExp.$9;
				if(/_globe:(?!earth|_|$)/i.test(params)) return;
				if(/_type:(adm3rd|city|mountain|isle|river|waterbody)/.test(params))scale = 100000;
				else if(/_type:(event|forest|glacier)/.test(params))scale = 50000;
				else if(/_type:(airport|edu|pass|landmark|railwaystation)/.test(params))scale = 10000;
				else scale = 300000;
				if(/_dim:(+)(km)?m?/.exec(params))scale = RegExp.$1 * (RegExp.$2?10000:10);
				if(/_scale:(\d+)(_|$)/.exec(params))scale = RegExp.$1;
				var osmzoom = 18 - Math.round(Math.log(scale/1693) / Math.log(2));
				var zoom =  Math.log( 1.5e8/scale) / Math.log(2);
				
				// Replace link
				var replacement_url = ghrs_mapprovider.replace(/\{latdegdec\}/g, lat).replace(/\{londegdec\}/g, lon).replace(/\{scale\}/g, scale).replace(/\{span\}/g, scale/1e6).replace(/\{osmzoom\}/g, osmzoom).replace(/\{zoom\}/g, zoom); 
				$(this).attr("href", replacement_url).parent().removeClass("plainlinks").parent().removeClass("plainlinks");
			}
		});
	};
	// Hook on to changes in page content, including initial load
	mw.hook('wikipage.content').add(replaceLinks);
	// Hook onto wikibase UI rendered (i.e. Wikidata mainspace)
	mw.hook('wikibase.entityPage.entityView.rendered').add(function() {
		// Coords statements have geohack links in kartographer map captions.
		// However, initially they are just plain text, and are made into a link
		// after a short delay. So for each caption, at intervals of 250ms, we
		// check if the link has appeared - until the link is found (and then we
		// can replace it), or until the 20th repition (to avoid infinite loop). 
		if ( !$(".wikibase-kartographer-caption").length ) { return; }
		$(".wikibase-kartographer-caption").each(function() {
			var interval,
				repitions = 0,
				context = this;
			interval = setInterval(function () {
				var $caption = $(context);
				if ( $caption.find("a").length ) {
					replaceLinks($caption);
					clearInterval(interval);
					return;
				}
				if (repitions === 20) {
					clearInterval(interval);
					return;
				}
				repitions++;
			}, 250);
		});
	});
});