script.js

var plistString = '';
var doc;
var folder = '/some/folder/path';

var onRun = function(context) {
    doc = context.document;

    // Start a new document
    plistString += "<?xml version='1.0' encoding='UTF-8'?>";
    plistString += "\n<!DOCTYPE plist PUBLIC '-//Apple//DTD PLIST 1.0//EN' 'http://www.apple.com/DTDs/PropertyList-1.0.dtd'>";
    plistString += "\n<plist version='1.0'>";
    plistString += "\n<array>";
    
    artboards = doc.artboards();
    for( var i = artboards.count()-1; i >= 0 ; i--) {
        var artboard = [artboards objectAtIndex:i];
        var layers = artboard.layers();

        // Start a new lesson plist
        plistString += "\n  <dict>";
        
        // Find/add lesson identifier
        plistString += "\n    <key>lesson_identifier</key>";
        plistString += "\n    <string>" + artboard.name() + "</string>";

        // Find rest of metadata
        var metadataGroup = [layers objectAtIndex:layers.count()-1];
        var metadataGroupLayers = metadataGroup.layers();
        for (var j = 0; j < metadataGroupLayers.count(); j++) {
            var metadataLayer = [metadataGroupLayers objectAtIndex:j];
            if( metadataLayer.class() == 'MSTextLayer' ){
                plistString += "\n    <key>" + metadataLayer.name() + "</key>";
                plistString += "\n    <string>" + metadataLayer.stringValue() + "</string>";
            }
        };

        // Add lesson items
        plistString += "\n    <key>lesson_items</key>";
        plistString += "\n    <array>";

        // Go through each layer in the artboard
        for( var j = layers.count()-1; j >= 0 ; j--) {
            var layer = [layers objectAtIndex:j];
            saveLayer(layer,artboard.name());
        }
        plistString += "\n    </array>";

        // End lesson
        plistString += "\n  </dict>";
    }

    // End a new document
    plistString += "\n</array>";
    plistString += "\n</plist>";

    log(plistString);
    var s = [[NSString alloc] initWithString:plistString];
    [s writeToFile:folder+"lessons.plist" atomically:true encoding:NSUTF8StringEncoding error:null];
};

function saveLayer(layer,artboard_name){
    if( layer.name() == "Background" ){
        log("Skipping layer named 'Background'");
        return;
    }
    else{
        if( layer.class() == 'MSTextLayer' ){
            if( layer.name() == 'title' ){
                saveTitleLayer(layer);
            }else if( layer.name() == 'subtitle' ){
                saveSubtitleLayer(layer);
            }else{
                saveTextLayer(layer);
            }
        }
        else if( layer.class() == 'MSSliceLayer' ){
            saveSliceLayer(layer,artboard_name);
        }
        else if( layer.class() == 'MSLayerGroup'){
            // skip
        }
    }
}

function saveTitleLayer(layer){
    plistString += '\n      <dict>';
    plistString += '\n        <key>page_type</key>';
    plistString += '\n        <string>title</string>';
    plistString += '\n        <key>page_content</key>';
    plistString += '\n        <string>'+ layer.stringValue() +'</string>';
    plistString += '\n      </dict>';    
}

function saveSubtitleLayer(layer){
    plistString += '\n      <dict>';
    plistString += '\n        <key>page_type</key>';
    plistString += '\n        <string>title</string>';
    plistString += '\n        <key>page_style</key>';
    plistString += '\n        <string>subtitle</string>';
    plistString += '\n        <key>page_content</key>';
    plistString += '\n        <string>'+ layer.stringValue() +'</string>';
    plistString += '\n      </dict>';    
}

function saveTextLayer(layer){
    plistString += '\n      <dict>';
    plistString += '\n        <key>page_type</key>';
    plistString += '\n        <string>text</string>';
    plistString += '\n        <key>page_content</key>';
    plistString += '\n        <string>'+ layer.stringValue() +'</string>';
    plistString += '\n      </dict>';
}

function saveSliceLayer(layer,artboard_name){
    // Write to file
    var file = folder + artboard_name + "_" + [layer name] + "@2x.png";
    [doc saveArtboardOrSlice:layer toFile:file];

    //log("Exporting slice layer named: " + layer.name() + " to path: " + file);
    plistString += '\n      <dict>';
    plistString += '\n        <key>page_type</key>';
    plistString += '\n        <string>image</string>';
    plistString += '\n        <key>page_content</key>';
    plistString += '\n        <string>'+ artboard_name + "_" + layer.name() +'</string>';
    plistString += '\n      </dict>';
}