header={
  "recipe_version": "1.12",
  "title": "Detect video chapters",
  "description": "Add chapters to a video using ffmpeg automatic scene change detection",
  "tags": "default",
  "chef": "BeatRig",
  "dependencies": "ffprobe,ffmpeg",
  "spice": "BQ==:G+Hy36kJcnQQYYavb/JV2Il6eCYr6h4hRJHCF9rRbhX5BcazL6cuTgUMdz0xA50VWA5PmmV0Q7aWkiUtNFtbk991l+t0e8IBXMReMIT1GNjnZZDv7n2YRAo0xcSQbY0ixjG6LLH4wGKnspKAoA/v69iLn6N2IH0XzIZwTGdHSo4=",
  "flavour": "SQ++6SwhLs7yy/tRoTktVDMwiWHexUzcQFH//4T9yRyKzAzfAQmwBCIa+GJUb4HCLyV0KlXi1PqZ/n1n67hkjGnNkC7PM4jTrkBZuFuJ51f3e0GSaBaZvTg3HUcAywPxDgGVL6uiO5wNZaZAVehf2udtu0yrIdAeQSuLJi0bGl0=",
  "time": 1694210484,
  "core_version": "0.5.7",
  "magnetron_version": "1.0.261",
  "functions": "main",
  "uuid": "d18f14dbd9af4b43be368a3b9afbabd2",
  "instructions": "Drop a video file and hit run to make a copy with chapters added",
  "type": "default",
  "os": "windows,macOS",
  "palette": "Clean Slate"
};

//----------------------------------------------------------------------------
function getDur(infile)
{
    var probeoutput = cmd("ffprobe", [infile]);
    var dur_tc = findSubString(probeoutput, "Duration: ", ", s");    
    return calculateSeconds(dur_tc);    
}

function calculateSeconds(dur_tc)
{
    var hours = (dur_tc.substring(0, 2));
    var minutes = (dur_tc.substring(3, 3+2));
    var seconds = (dur_tc.substring(6, 6+2));
    if (hours.substring(0, 1) == "0")
        hours = hours.substring(1,2);
    if (minutes.substring(0, 1) == "0")
        minutes = minutes.substring(1,2);
    if (seconds.substring(0, 1) == "0")
        seconds = seconds.substring(1,2);
    hours = parseInt(hours);
    minutes = parseInt(minutes);
    seconds = parseInt(seconds);
    
    totalsec = (hours * 60 * 60) + (minutes * 60) + seconds;
    return totalsec;
}

function convertExpNotFloat(str)
{
    pos = (str + "").indexOf('e'); // [coefficient, exponent]
    if (pos > 0)
    {
        x = toFixed(str, 1); // allow 1 dec to negate exponent
        return x.substring(0, x.length-2); // cut off . and decimal
    }    
    return str;
}

function main()
{
    items = getItems();
    files = getFiles();
    items.numfiles = 1;

    if (files.length > 0)
    {
        inputpath = files[0]["path"];
        var inputinfo = getPathInfo(inputpath);
        if (inputinfo)
            outputpath = inputinfo.folder;// + info.sep + info.basename + "-chapters." + info.ext;
    }
    else
    {
        inputpath = "";
        outputpath = "";
    }
    echo(outputpath);

    form = {
        "header" : {
            "type" : "text",
            "label" : "This process will add chapters in videos at scene changes",
            "just" : "l",
            "bounds" : { 
                "x": 10, 
                "y" : 5, 
                "w" : 600, 
            }, 
        },
        "file1_header" : {
            "type" : "text",
            "label" : "source file",
            "just" : "l",
            "bounds" : { 
                "w" : 120, 
            }, 
        },
        "inputfile" : {
            "type" : "fileselect",
            "path" : inputpath,
            "editable" : false,
            "dir" : false,
            "saving" : false,
            "label" : "source file",
            "bounds" : {
                "x" : 130,
                "y" : -1, 
                "w" : 470,
            }, 
        },
        "sens_header" : {
            "type" : "text",
            "label" : "detection sensitivity",
            "just" : "l",
            "bounds" : { 
                "w" : 180,
            }, 
        },
        "sens": { 
            "type": "slider", 
            "style": "slider_h",
            "visible": true, 
            "range" : { 
                "min": 0.01, 
                "max" : 1., 
                "interval" : 0.01, 
                "decimals" : 2 
            }, 
            "bounds" : {
                "x" : 190,
                "y" : -1, 
                "w" : 280,
            }, 
            "value": 0.45 
        }, 
        "sens_label" : {
            "type" : "text",
            "label" : "default",
            "just" : "c",
            "bounds" : { 
                "x": 480, 
                "y" : -1, 
                "w" : 120, 
            }, 
        },

        "chapterlength_header" : {
            "type" : "text",
            "label" : "minimum chapter secs",
            "just" : "l",
            "bounds" : { 
                "w" : 180,
            }, 
        },
        "chapterlength": { 
            "type": "slider", 
            "style": "slider_h",
            "visible": true, 
            "range" : { 
                "min": 1, 
                "max" : 60 * 30, 
                "interval" : 1, 
                "decimals" : 0 
            }, 
            "bounds" : {
                "x" : 190,
                "y" : -1, 
                "w" : 360,
            }, 
            "value": 15
        },
        "file2_header" : {
            "type" : "text",
            "label" : "output folder",
            "just" : "l",
            "bounds" : { 
                "w" : 120, 
            }, 
        },
        "outputfile" : {
            "type" : "fileselect",
            "path" : outputpath,
            "editable" : false,
            "dir" : true,
            "saving" : true,
            "label" : "select output folder",
            "bounds" : {
                "x" : 130,
                "y" : -1, 
                "w" : 470,
            }, 
        },
        "okay" : {
            "type" : "button",
            "label" : "Start",
            "bounds" : { 
                "w" : 280, 
            }, 
            "returns" : 1
        },
        "cancel" : {
            "type" : "button",
            "label" : "cancel",
            "bounds" : { 
                "y": -1,
                "x": 320,
                "w" : 280
            }, 
            "returns" : 0
        },
    };
    
    var r = dialog(form);
    echo(objectToString(r));

    if (r.okay == false)
        return;

    if (r.inputfile != "undefined")
    {
        var info = getPathInfo(r.inputfile);
        if (r.outputfile == "")
            outpath = info.foldder + gvar.pss + info.basename + "-chapters." + info.ext;
        else outpath = r.outputfile + gvar.pss + info.basename + "-chapters." + info.ext;

        items.totalsec = getDur(info.path);
        items.fileindex = i;
        items.part = 0;
        items.terminated = false;
        items.numfiles = 1;
        setItems(items);
        echo("total sec:" + totalsec);

        if(isCanceled())
            return;

        setMainMessage("Detect scene changes");
        setProgress(10);

        sensitivity = r.sens;
        ffmpegArgs = ["-y",
            "-i",
            r.inputfile,
            "-vf",
            "select='gt(scene," + toFixed(1. - sensitivity, 2) + ")',showinfo"
        ];

        ffmpegArgs.push("-f");
        ffmpegArgs.push("null");
        ffmpegArgs.push("-");


        echo(objectToString(ffmpegArgs));
        var rawScenedata = (cmd("ffmpeg", ffmpegArgs));
        echo(rawScenedata);
        var sceneSecs = searchRegEx(rawScenedata, "pts_time:\s*([^\s]+)", "i", -1);
        items = getItems();
        
        if (items.terminated)
            abort("failed to process file\ntry using the large muxing queue option");

        if(isCanceled())
            return;

        setMainMessage("Filter scenes");
        setProgress(80);

        var sceneSecsFilter = [];
        var sec=0.;
        for (j=0; j<sceneSecs.length; j++)
        {
            x = parseFloat(sceneSecs[j]);
            if (x - sec > r.chapterlength) // minimal 10 sec
            {
                sceneSecsFilter.push(x);
                sec = x;
            }
        }
        if (parseFloat(items.totalsec) > sceneSecsFilter[sceneSecsFilter.length-1])
            sceneSecsFilter.push(items.totalsec); // add total length as end
        else sceneSecsFilter.push(sceneSecsFilter[sceneSecsFilter.length-1] + 1);
        echo("scene secs: " + objectToString(sceneSecsFilter));

        var chapters = "\n";
        for (j=0;j<sceneSecsFilter.length-1;j++)
        {
          /*[CHAPTER]
            TIMEBASE=1/1000
            START=1
            END=448000
            title=Magnetron */
            start = convertExpNotFloat(sceneSecsFilter[j] * 1000.);
            end = convertExpNotFloat((sceneSecsFilter[j+1] * 1000.) - 1);

            chapters += "[CHAPTER]\nTIMEBASE=1/1000\nSTART=" + start + 
                        "\nEND=" + end + 
                        "\ntitle=Chapter-" + (j + 1) + "\n\n";
        }

        items.part = 1;
        setItems(items);

        if(isCanceled())
            return;
    
        setMainMessage("get original metadata");
        setProgress(90);

        metadata_txt_path = folders.temp + gvar.pss + "metadata.txt";
        makeFolder(folders.temp);        
        ffmpegArgsExtract = ["-y",
            "-i",
            info.path,
            "-f",
            "ffmetadata",
            metadata_txt_path
        ];
        echo(objectToString(ffmpegArgsExtract));        
        var rawExtractData = cmd("ffmpeg", ffmpegArgsExtract);
        echo(rawExtractData);

        // add metadata
        appendFile(metadata_txt_path, chapters);
        echo(chapters);
        
        setMainMessage("mux new metadata into video");
        setProgress(95);

        ffmpegArgs2 = ["-y",            
            '-i',
            info.path,
            '-i',
            metadata_txt_path,
            '-map',
            '0',
            '-map_metadata',
            '1',
            '-c',
            'copy',
            outpath
        ];
        echo(objectToString(ffmpegArgs2));
        echo(cmd("ffmpeg", ffmpegArgs2));
    }

    setProgress(100);
    setMainMessage("done");
}

// ---------------------------------------------------------------------
function cmd_callback(cmd_name, cmd_output)
{
    if(cmd_name == "ffmpeg" && cmd_output.length > 0)
    {
        packet = findSubString(cmd_output, "Error submitting a ", " to the muxer"); // packet
        if (packet != "packet")
        {
            items = getItems();
            var progressSec = calculateSeconds(findSubString(cmd_output, "time=", " bitrate"));
            progress = 10. + Math.round((progressSec / items.totalsec * (70. / 2. / items.numfiles)) + ((70. / items.numfiles) * items.fileindex) + (70. / 2. / items.numfiles * items.part));
            setProgress(progress);
            setMainMessage((progress) + "%");
        }
        else
        {
            items = getItems();
            items.terminated = true;
            setItems(items);
            return { "terminate": true };    
        }
    }

    return {
        "terminate": isCanceled(),
        "input": ""
    };
}

function dialog_callback(props)
{
    if (props["name"] == "inputfile")
    {
        var info = getPathInfo(props["path"]);
        var newprops;
        newprops = { "outputfile" : { "path" : info.folder } };
        
        dialog(newprops);
    }
    if (props["name"] == "sens")
    {
        var newprops;
        if (props["value"] < 0.25)
            newprops = { "sens_label" : { "label" : "few chapters" } };
        else if (props["value"] < 0.5)
            newprops = { "sens_label" : { "label" : "less chapters" } };
        else if (props["value"] < 0.75)
            newprops = { "sens_label" : { "label" : "more chapters" } };
        else newprops = { "sens_label" : { "label" : "many chapters" } };
        
        dialog(newprops);
    }
}