// This function will remove the matching amendment for this entry (id)
// can only have 1 ammendment per image, its grayed out for other changes
function removeAmendment( id )
{
   document.amendments=document.amendments.filter(obj => obj.eid !== id)
}

// POST to a check URL, that will tell us if the transformation has completed,
// if not, try again in 1 second... If it has finished then reset the thumbnail
// to full colour, put it back to being an entry and reset the thumbnail to the
// newly created one that was sent back in the response to the POST
function handleTransformFiles(data,id,job_id)
{
    if( data.finished )
    {
        id=parseInt(id)
        idx = entryList.indexOf(id)
        // replace data for this entry now its been transformed
        document.entries[idx]=data.entry
        // update cache too
        // document.page[getPageNumberForId(id)][howFarIntoPageCache(id)]=data.entry
        // FIXME: for now just invalidate whole cache
        document.page.length=0
        removeAmendment( id )
        // redraw into figure html in dom
        last={ 'printed': 'not required' }
        html = createFigureHtml( data.entry, last, 9999 )
        $('#'+id).replaceWith( html )
        return false;
    }
    else
    {
        setTimeout( function() { CheckTransformJob(id,job_id,handleTransformFiles) }, 1000,id, job_id );
    }
}

// POST to a check URL, that will tell us if the transformation has completed,
// if not, try again in 1 second... If it has finished then reset the image
// to full colour
function handleTransformViewing(data,id,job_id)
{
    if( data.finished )
    {
        // stop throbber, remove grayscale & then force reload with timestamped version of im.src
        im.src=im.src + '?t=' + new Date().getTime();
        removeAmendment( id )
        return false;
    }
    else
    {
        setTimeout( function() { CheckTransformJob(id,job_id,handleTransformViewing) }, 1000,id, job_id );
    }
}

// POST to a check URL, that will tell us if the transformation has completed,
// if not, try again in 1 second... If it has finished then reset the thumbnail
// to full colour, put it back to being an entry and reset the thumbnail to the
// newly created one that was sent back in the response to the POST
function CheckTransformJob(id,job_id,successCallback)
{
    CheckForJobs()
    $.ajax( { type: 'POST', data: '&job_id='+job_id, url: '/check_transform_job', 
        success: function(res) { successCallback(res,id,job_id); } } )
}

// function to add data for document.amendment based on id and amt
// used when we transform several images in files_*, or single image in viewer
function addTransformAmendment(id,amt)
{
    am={}
    am.eid=parseInt(id)
    am.type = document.amendTypes.filter(obj => obj.job_name === 'transform_image:'+amt )[0]
    document.amendments.push(am)
}

// for each highlighted image, POST the transform with amt (90, 180, 270,
// fliph, flipv) which will let the job manager know what to do to this file.
// we also grayscale the thumbnail out, remove the entry class for now, show
// the spinning wheel, and finally kick of the checking for the transform job
// to finish
function Transform(amt)
{
    // we are in the viewer with 1 image only...
    if( document.viewing )
    {
        post_data = '&amt='+amt+'&id='+document.viewing.id
        // POST /transform for image, grayscale the image, add throbber, & start checking for end of job
        $.ajax({ type: 'POST', data: post_data, url: '/transform', success: function(data) { 
            addTransformAmendment(document.viewing.id, amt)
            DrawImg();
            CheckTransformJob(document.viewing.id,data.job_id,handleTransformViewing);
            return false; 
        } })
    }
    else
    {
        $('.highlight').each(function( cnt, e ) {
            post_data = '&amt='+amt+'&id='+e.id
            // POST /transform for image, grayscale the thumbnail, add throbber, & start checking for end of job
            $.ajax({ type: 'POST', data: post_data, url: '/transform', success: function(data){ 
                addTransformAmendment(e.id, amt)
                last={ 'printed': 'not required' }
                idx = pageList.indexOf(parseInt(e.id))
                html = createFigureHtml( document.entries[idx], last, 9999 )
                $('#'+e.id).replaceWith( html )
                CheckTransformJob(e.id,data.job_id,handleTransformFiles);
                return false; 
            } })
        } )
    }
}