c@117: "use strict";
c@117: 
c@117: function note(blah) {
c@117:     document.getElementById("test-result").innerHTML += blah + "<br>";
c@117: }
c@117: 
c@117: function comment(blah) {
c@117:     note("<br><i>" + blah + "</i>");
c@117: }
c@117: 
c@117: function test() {
c@117: 
cannam@175:     VampExamplePluginsModule().then(function(exampleModule) {
cannam@175:         
cannam@175:         // It is possible to declare both parameters and return values
cannam@175:         // as "string", in which case Emscripten will take care of
cannam@175:         // conversions. But it's not clear how one would manage memory
cannam@175:         // for newly-constructed returned C strings -- the returned
cannam@175:         // pointer from piperRequestJson would appear (?) to be thrown
cannam@175:         // away by the Emscripten string converter if we declare it as
cannam@175:         // returning a string, so we have no opportunity to pass it to
cannam@175:         // piperFreeJson, which suggests this would leak memory if the
cannam@175:         // string isn't static. Not wholly sure though. Anyway,
cannam@175:         // passing and returning pointers (as numbers) means we can
cannam@175:         // manage the Emscripten heap memory however we want in our
cannam@175:         // request wrapper function below.
c@117: 
cannam@175:         var piperRequestJson = exampleModule.cwrap(
cannam@175:             'piperRequestJson', 'number', ['number']
cannam@175:         );
cannam@175:         
cannam@175:         var piperFreeJson = exampleModule.cwrap(
cannam@175:             'piperFreeJson', 'void', ['number']
cannam@175:         );
c@117: 
cannam@175:         function request(jsonStr) {
cannam@175:             note("Request JSON = " + jsonStr);
cannam@175:             var m = exampleModule;
cannam@175:             // Inspection reveals that intArrayFromString converts the
cannam@175:             // string from utf16 to utf8, which is what we want
cannam@175:             // (though the docs don't mention this). Note the *Cstr
cannam@175:             // values are Emscripten heap pointers
cannam@175:             var inCstr = m.allocate(m.intArrayFromString(jsonStr), 'i8', m.ALLOC_NORMAL);
cannam@175:             var outCstr = piperRequestJson(inCstr);
cannam@175:             m._free(inCstr);
cannam@176:             var result = m.UTF8ToString(outCstr);
cannam@175:             piperFreeJson(outCstr);
cannam@175:             note("Returned JSON = " + result);
cannam@175:             return result;
cannam@175:         }
c@117: 
cannam@175:         comment("Querying plugin list...");
cannam@175:         var result = request('{"method": "list"}');
c@117: 
cannam@175:         comment("Loading zero crossings plugin...");
cannam@175:         result = request('{"method":"load","params": {"key":"vamp-example-plugins:powerspectrum","inputSampleRate":16,"adapterFlags":["AdaptAllSafe"]}}');
c@117: 
cannam@175:         comment("I'm now assuming that the load succeeded and the returned handle was 1. I haven't bothered to parse the JSON. If those assumptions are wrong, this obviously isn't going to work. Configuring the plugin...");
cannam@175:         result = request('{"method":"configure","params":{"handle":1,"configuration":{"framing": { "blockSize": 8, "stepSize": 8 }, "channelCount": 1 }}}');
c@117: 
cannam@175:         comment("If I try to configure it again, it should fail because it's already configured... but this doesn't change anything, and subsequent processing should work fine. Just an example of a failure call. NB this only works if Emscripten has exception catching enabled -- it's off by default in opt builds, which would just end the script here. Wonder what the performance penalty is like.");
cannam@175:         result = request('{"method":"configure","params":{"handle":1,"configuration":{"framing": { "blockSize": 8, "stepSize": 8 }, "channelCount": 1 }}}');
cannam@175: 
cannam@175:         comment("Now processing a couple of blocks of data, on the same assumptions...");
cannam@175:         result = request('{"method":"process","params":{"handle":1,"processInput":{"timestamp":{"s":0,"n":0},"inputBuffers":[[0,1,-1,0,1,-1,0,1]]}}}');
cannam@175:         result = request('{"method":"process","params":{"handle":1,"processInput":{"timestamp":{"s":0,"n":500000000},"inputBuffers":[[0,1,-1,0,1,-1,0,1]]}}}');
cannam@175: 
cannam@175:         comment("Cleaning up the plugin and getting any remaining features...");
cannam@175:         result = request('{"method":"finish","params":{"handle":1}}');
cannam@175: 
cannam@175:         comment("A process call should now fail, as the plugin has been cleaned up.");
cannam@175:         result = request('{"method":"process","params":{"handle":1,"processInput":{"timestamp":{"s":0,"n":1000000000},"inputBuffers":[{"values":[0,1,-1,0,1,-1,0,1]}]}}}');
cannam@175:     });
c@117: }
c@117: 
c@117: window.onload = function() {
c@117:     test();
c@117: }