// script that recognizes images or performs some kind of analysis on an image
concept G22Analyzer > G22LeftArrowScript {
  new Ref<G22GalleryImage> exampleImage;
  
  @Override GazelleV_LeftArrowScriptParser makeParser() {
    var parser = super.makeParser();
    parser.addVar("image", BufferedImage.class, false);
    parser.addVar("imageStream", SourceTriggeredStream.class, false);
    parser.addVar("context", G22AnalysisContext.class, false);
    ret parser;
  }
  
  class CompiledAnalyzer > LASCompileResult {
    settable double timeout = 10;
    
    G22AnalysisContext createAnalysisContext(BufferedImage image) {
      ret new G22AnalysisContext(g22utils(), image);
    }

    // evaluate directly without registration or timeout
    O get_impl(G22AnalysisContext context) {
      new FlexibleVarContext ctx;
      ctx.set(image := context.image);
      ctx.set(imageStream := context.imageStream);
      ctx.set(+context);
      ret parsedScript.get(ctx);
    }
    
    O get_impl(BufferedImage image) {
      ret get_impl(createAnalysisContext(image));
    }
    
    O get(BufferedImage image) {
      ret get(createAnalysisContext(image));
    }
    
    O get(G22AnalysisContext context) {
      if (context.analyzerResults.containsKey(analyzer())) {
        O value = context.analyzerResults.get(analyzer());
        if (value == G22AnalysisContext.calculating)
          fail("Recursive call to analyzer " + this);
        ret ((OKOrError) value).getMandatory();
      }
      context.analyzerResults.put(analyzer(), G22AnalysisContext.calculating);
      
      var result = okOrError(-> {
        if (parsedScript == null) rethrow(compileError);
        if (context.image == null
          && context.imageStream == null)
          fail("Need image or imageStream");
        
        ret g22utils().evalRegisteredCode(timeout, str(G22Analyzer.this),
          -> get_impl(context));
      });
      context.analyzerResults.put(analyzer(), result);
      ret result.getMandatory();
    }
  }
  
  selfType analyzer() { this; }
  
  LASCompileResult newCompileResult() { ret new CompiledAnalyzer; }
  
  CompiledAnalyzer compileForAutoRun() {
    ret (CompiledAnalyzer) super.compileForAutoRun();
  }
}

Began life as a copy of #1034256