/**
Parse student code
Analyze student code
Run student code
Run instructor code
Output feedback

# Within the instructor code you can surpress certain kinds of feedback
surpress_syntax()
surpress_empty()
surpress_algorithm()
surpress_runtime()
surpress_runtime('NameError')

# Or explicitly run certain kinds of analyses
run_student()
run_abstract()
*/

    
    /**
     * Given source code as a string, return a list of all of the AST elements
     * that are Num (aka numeric literals) but that are not inside List elements.
     *
     * @param {String} source - Python source code.
     * @returns {Array.number} The list of JavaScript numeric literals that were found.
     */
    function getNonListNums(source) {
        if (!(source in parses)) {
            var parse = Sk.parse("__main__", source);
            parses[source] = Sk.astFromParse(parse.cst, "__main__", parse.flags);
        }
        var ast = parses[source];
        var visitor = new NodeVisitor();
        var insideList = false;
        var nums = [];
        visitor.visit_List = function(node) {
            insideList = true;
            this.generic_visit(node);
            insideList = false;
        }
        visitor.visit_Num = function(node) {
            if (!insideList) {
                nums.push(node.n);
            }
            this.generic_visit(node);
        }
        visitor.visit(ast);
        return nums;
    }
    
    /**
     * Given source code as a string, return a list of all of the AST elements
     * that are being printed (using the print function) but are not variables.
     *
     * @param {String} source - Python source code.
     * @returns {Array.<Object>} The list of AST elements that were found.
     */
    function getPrintedNonProperties(source) {
        if (!(source in parses)) {
            var parse = Sk.parse("__main__", source);
            parses[source] = Sk.astFromParse(parse.cst, "__main__", parse.flags);
        }
        var ast = parses[source];
        var visitor = new NodeVisitor();
        var nonVariables = [];
        visitor.visit_Call = function(node) {
            var func = node.func;
            var args = node.args;
            if (func._astname == 'Name' && func.id.v == 'print') {
                for (var i =0; i < args.length; i+= 1) {
                    if (args[i]._astname != "Name") {
                        nonVariables.push(args[i]);
                    }
                }
            }
            this.generic_visit(node);
        }
        visitor.visit(ast);
        return nonVariables;
    }
    
    /**
     * Skulpt function to iterate through the final state of
     * all the variables in the program, and check to see if they have
     * a given value.
     */
    mod.get_value_by_name = new Sk.builtin.func(function(name) {
        Sk.builtin.pyCheckArgs("get_value_by_name", arguments, 1, 1);
        Sk.builtin.pyCheckType("name", "string", Sk.builtin.checkString(name));
        name = name.v;
        var final_values = Sk.builtins._final_values;
        if (name in final_values) {
            return final_values[name];
        } else {
            return Sk.builtin.none.none$;
        }
    });

    mod.get_value_by_type = new Sk.builtin.func(function(type) {
        Sk.builtin.pyCheckArgs("get_value_by_type", arguments, 1, 1);
        
        var final_values = Sk.builtins._final_values;
        var result = [];
        for (var property in final_values) {
            if (final_values[property].tp$name == type.tp$name) {
                result.push(final_values[property]);
            }
        }
        return Sk.builtin.list(result);
    });
    
    mod.parse_json = new Sk.builtin.func(function(blob) {
        Sk.builtin.pyCheckArgs("parse_json", arguments, 1, 1);
        Sk.builtin.pyCheckType("blob", "string", Sk.builtin.checkString(blob));
        blob = blob.v;
        return Sk.ffi.remapToPy(JSON.parse(blob));
    });

    mod.get_property = new Sk.builtin.func(function(name) {
        Sk.builtin.pyCheckArgs("get_property", arguments, 1, 1);
        Sk.builtin.pyCheckType("name", "string", Sk.builtin.checkString(name));
        name = name.v;
        var trace = Sk.builtins._trace;
        if (trace.length <= 0) {
            return Sk.builtin.none.none$;
        }
        var properties = trace[trace.length-1]["properties"];
        for (var i = 0, len = properties.length; i < len; i += 1) {
            if (properties[i]['name'] == name) {
                return Sk.ffi.remapToPy(properties[i])
            }
        }
        return Sk.builtin.none.none$;
    });
    
    mod.calls_function = new Sk.builtin.func(function(source, name) {
        Sk.builtin.pyCheckArgs("calls_function", arguments, 2, 2);
        Sk.builtin.pyCheckType("source", "string", Sk.builtin.checkString(source));
        Sk.builtin.pyCheckType("name", "string", Sk.builtin.checkString(name));
        
        source = source.v;
        name = name.v;
        
        var ast_list = getParseList(source);
        
        var count = 0;
        for (var i = 0, len = ast_list.length; i < len; i = i+1) {
            if (ast_list[i]._astname == 'Call') {
                if (ast_list[i].func._astname == 'Attribute') {
                    count += Sk.ffi.remapToJs(ast_list[i].func.attr) == name | 0;
                } else if (ast_list[i].func._astname == 'Name') {
                    count += Sk.ffi.remapToJs(ast_list[i].func.id) == name | 0;
                }   
            }
        }
        
        return Sk.ffi.remapToPy(count > 0);
    });
    
    mod.count_components = new Sk.builtin.func(function(source, component) {
        Sk.builtin.pyCheckArgs("count_components", arguments, 2, 2);
        Sk.builtin.pyCheckType("source", "string", Sk.builtin.checkString(source));
        Sk.builtin.pyCheckType("component", "string", Sk.builtin.checkString(component));
        
        source = source.v;
        component = component.v;
        
        var ast_list = getParseList(source);
        
        var count = 0;
        for (var i = 0, len = ast_list.length; i < len; i = i+1) {
            if (ast_list[i]._astname == component) {
                count = count+1;
            }
        }
        
        return Sk.ffi.remapToPy(count);
    });
    
    mod.no_nonlist_nums = new Sk.builtin.func(function(source) {
        Sk.builtin.pyCheckArgs("no_nonlist_nums", arguments, 1, 1);
        Sk.builtin.pyCheckType("source", "string", Sk.builtin.checkString(source));
        
        source = source.v;
        
        var num_list = getNonListNums(source);
        
        var count = 0;
        for (var i = 0, len = num_list.length; i < len; i = i+1) {
            if (num_list[i].v != 0 && num_list[i].v != 1) {
                return Sk.ffi.remapToPy(true);
            }
        }
        return Sk.ffi.remapToPy(false);
    });

    mod.only_printing_properties = new Sk.builtin.func(function(source) {
        Sk.builtin.pyCheckArgs("only_printing_properties", arguments, 1, 1);
        Sk.builtin.pyCheckType("source", "string", Sk.builtin.checkString(source));
        
        source = source.v;
        
        var non_var_list = getPrintedNonProperties(source);
        return Sk.ffi.remapToPy(non_var_list.length == 0);
    });
    
/**
     * Given a feedback string, records the corrective feedback string for later printing
     * @param {string} feedback - the piece of feedback to save
    **/
    mod.add_interrupt_feedback = new Sk.builtin.func(function(feedback) {
        Sk.builtin.pyCheckArgs("add_interupt_feedback", arguments, 1, 1);
        Sk.builtin.pyCheckType("feedback", "string", Sk.builtin.checkString(feedback));
        accInterruptFeedback.push(feedback);
    });

    /**
     * Given a feedback string, records the complementary feedback string for later printing
     * @param {string} feedback - the piece of feedback to save
    **/
    mod.add_comp_feedback = new Sk.builtin.func(function(feedback) {
        Sk.builtin.pyCheckArgs("add_comp_feedback", arguments, 1, 1);
        Sk.builtin.pyCheckType("feedback", "string", Sk.builtin.checkString(feedback));
        accCompFeedback.push(feedback);
    });

    /**
     * This resolves all of the feedback and posts it to the appropriate places
     * @TODO: actually implement this functionality
    **/
    mod.post_feedback = new Sk.builtin.func(function() {
        var allFeedback = accInterruptFeedback.concat(accCompFeedback);
        completePythonAll = Sk.builtin.list(allFeedback);
        jsPureFeedback = Sk.ffi.remapToJs(completePythonAll);
        console.log("" + jsPureFeedback);
    });


Sk.builtins.value = new Sk.builtin.func(function() {
    return Sk.ffi.remapToPy(GLOBAL_VALUE === undefined ? 5 : GLOBAL_VALUE);
});
Sk.builtins.set_value = new Sk.builtin.func(function(v) {
    GLOBAL_VALUE = v.v;
});


/**
 * Runs the given python code, resetting the console and Trace Table.
 */
BlockPyEngine.prototype.run = function() {
    // Reset everything
    this.resetExecution();
    
    if (!this.main.model.settings.disable_semantic_errors() &&
        !this.main.model.assignment.disable_algorithm_errors()) {
        var success = this.analyze();
        if (success === false) {
            this.executionEnd_();
            this.main.components.server.markSuccess(0.0);
            return;
        }
    }
    
    this.main.model.execution.status("running");
    
    var feedback = this.main.components.feedback;
    
    // Get the code
    var code = this.main.model.programs['__main__']();
    if (code.trim() == "") {
        feedback.emptyProgram();
        this.main.model.execution.status("error");
        this.executionEnd_();
        this.main.components.server.markSuccess(0.0);
        return;
    }
    // Actually run the python code
    var executionPromise = Sk.misceval.asyncToPromise(function() {
        return Sk.importMainWithBody("<stdin>", false, code, true);
    });
    
    var engine = this;
    var server = this.server;
    var execution = this.main.model.execution;
    executionPromise.then(
        function (module) {
            // Run the afterSingleExecution one extra time for final state
            Sk.afterSingleExecution(module.$d, -1, 0, "<stdin>.py");
            engine.lastStep();
            // Handle checks
            feedback.noErrors()
            engine.check(code, execution.trace(), execution.output(), execution.ast, module.$d);
            // Reenable "Run"
            engine.main.model.execution.status("waiting");
            engine.executionEnd_();
        },
        function(error) {
            feedback.printError(error);
            engine.main.model.execution.status("error");
            engine.executionEnd_();
            server.markSuccess(0.0);
            //server.logEvent('blockly_error', error);
        }
    );
}

BlockPyEngine.prototype.setupEnvironment = function(student_code, traceTable, output, ast, final_values) {
    var model = this.main.model;
    this._backup_execution = Sk.afterSingleExecution;
    Sk.afterSingleExecution = undefined;
    Sk.builtins.get_output = new Sk.builtin.func(function() { 
        Sk.builtin.pyCheckArgs("get_output", arguments, 0, 0);
        return Sk.ffi.remapToPy(model.execution.output());
    });
    Sk.builtins.reset_output = new Sk.builtin.func(function() { 
        Sk.builtin.pyCheckArgs("reset_output", arguments, 0, 0);
        model.execution.output.removeAll();
    });
    Sk.builtins.log = new Sk.builtin.func(function(data) { 
        Sk.builtin.pyCheckArgs("log", arguments, 1, 1);
        console.log(data)
    });
    //Sk.builtins.trace = Sk.ffi.remapToPy(traceTable);
    Sk.builtins._trace = traceTable;
    Sk.builtins._final_values = final_values;
    Sk.builtins.code = Sk.ffi.remapToPy(student_code);
    Sk.builtins.set_success = this.instructor_module.set_success;
    Sk.builtins.set_feedback = this.instructor_module.set_feedback;
    Sk.builtins.set_finished = this.instructor_module.set_finished;
    Sk.builtins.count_components = this.instructor_module.count_components;
    Sk.builtins.no_nonlist_nums = this.instructor_module.no_nonlist_nums;
    Sk.builtins.only_printing_properties = this.instructor_module.only_printing_properties;
    Sk.builtins.calls_function = this.instructor_module.calls_function;
    Sk.builtins.get_property = this.instructor_module.get_property;
    Sk.builtins.get_value_by_name = this.instructor_module.get_value_by_name;
    Sk.builtins.get_value_by_type = this.instructor_module.get_value_by_type;
    Sk.builtins.parse_json = this.instructor_module.parse_json;
    Sk.builtins.Stack = this.instructor_module.Stack;

    Sk.skip_drawing = true;
    model.settings.mute_printer(true);
}

BlockPyEngine.prototype.disposeEnvironment = function() {
    Sk.afterSingleExecution = this._backup_execution;
    Sk.builtins.get_output = undefined;
    Sk.builtins.reset_output = undefined;
    Sk.builtins.log = undefined;
    Sk.builtins._trace = undefined;
    Sk.builtins.trace = undefined;
    Sk.builtins.code = undefined;
    Sk.builtins.set_success = undefined;
    Sk.builtins.set_feedback = undefined;
    Sk.builtins.set_finished = undefined;
    Sk.builtins.count_components = undefined;
    Sk.builtins.calls_function = undefined;
    Sk.builtins.get_property = undefined;
    Sk.builtins.get_value_by_name = undefined;
    Sk.builtins.get_value_by_type = undefined;
    Sk.builtins.no_nonlist_nums = undefined;
    Sk.builtins.only_printing_properties = undefined;
    Sk.builtins.parse_json = undefined;
    Sk.skip_drawing = false;
    GLOBAL_VALUE = undefined;
    this.main.model.settings.mute_printer(false);
}

BlockPyEngine.prototype.check = function(student_code, traceTable, output, ast, final_values) {
    var engine = this;
    var server = this.main.components.server;
    var model = this.main.model;
    var on_run = model.programs['give_feedback']();
    if (on_run !== undefined && on_run.trim() !== "") {
        on_run = 'def run_code():\n'+indent(student_code)+'\n'+on_run;
        this.setupEnvironment(student_code, traceTable, output, ast, final_values);
        
        var executionPromise = Sk.misceval.asyncToPromise(function() {
            return Sk.importMainWithBody("<stdin>", false, on_run, true);
        });
        executionPromise.then(
            function (module) {
                engine.main.components.feedback.noErrors();
                engine.disposeEnvironment();
            }, function (error) {
                engine.disposeEnvironment();
                console.log(error.tp$name, error.tp$name == "Success");
                if (error.tp$name == "Success") {
                    server.markSuccess(1.0, model.settings.completedCallback);
                    engine.main.components.feedback.complete();
                } else if (error.tp$name == "Feedback") {
                    server.markSuccess(0.0);
                    engine.main.components.feedback.instructorFeedback("Incorrect Answer", error.args.v[0].v);
                } else if (error.tp$name == "Finished") {
                    server.markSuccess(1.0, model.settings.completedCallback);
                    engine.main.components.feedback.finished();
                } else {
                    console.error(error);
                    engine.main.components.feedback.internalError(error, "Feedback Error", "Error in instructor's feedback. Please show the above message to an instructor!");
                    server.logEvent('blockly_instructor_error', ''+error);
                    server.markSuccess(0.0);
                }
            });
    }
}

/**
 * Runs the AbstractInterpreter to get some static information about the code,
 * in particular the variables' types. This is needed for type checking.
 *
 * @returns {Object<String, AIType>} Maps variable names (as Strings) to types as constructed by the AbstractIntepreter.
 */
BlockPyEngine.prototype.analyzeVariables = function() {
    // Get the code
    var code = this.main.model.programs['__main__']();
    if (code.trim() == "") {
        return {};
    }
    
    var analyzer = new AbstractInterpreter(code);
    report = analyzer.report;
    return analyzer.variableTypes;
}

/**
 * Runs the AbstractInterpreter to get some static information about the code,
 * including potential semantic errors. It then parses that information to give
 * feedback.
 *
 * @returns {Boolean} Whether the code was successfully analyzed.
 */
BlockPyEngine.prototype.analyze = function() {
    this.main.model.execution.status("analyzing");
    
    var feedback = this.main.components.feedback;
    
    // Get the code
    var code = this.main.model.programs['__main__']();
    if (code.trim() == "") {
        this.main.components.feedback.emptyProgram("You haven't written any code yet!");
        //this.main.model.feedback.status("semantic");
        return false;
    }
    
    var analyzer = new AbstractInterpreter(code);
    this.main.model.execution.ast = analyzer.ast;
    
    report = analyzer.report;
    // Syntax error
    if (report.error !== false) {
        console.log(report.error.args.v)
        var codeLine = '.';
        if (report.error.args.v.length > 3) {
            codeLine = ', where it says:<br><code>'+report.error.args.v[3][2]+'</code>';
        }
        feedback.editorError(report.error, "While attempting to process your Python code, I found a syntax error. In other words, your Python code has a mistake in it (e.g., mispelled a keyword, bad indentation, unnecessary symbol). You should check to make sure that you have written all of your code correctly. To me, it looks like the problem is on line "+ report.error.args.v[2]+codeLine, report.error.args.v[2]);
        return false;
    }
        
    
    
    return true;
}

var GLOBAL_VALUE;