// Regression tests for the editor's real interpreter and output callback.
// Run: node scripts/test-cpp-regressions.cjs
const assert = require('assert');
const fs = require('fs');
const path = require('path');
const vm = require('vm');
const babel = require('@babel/core');
const parserPath = path.resolve(__dirname, '../src/components/stage-cpp/cpp-parser.js');
const source = fs.readFileSync(parserPath, 'utf8');
const compiled = babel.transformSync(source, {
    filename: parserPath, configFile: false, babelrc: false,
    plugins: ['@babel/plugin-transform-modules-commonjs'],
    presets: process.argv.includes('--transpiled') ? ['@babel/preset-env'] : []
}).code;
const silentConsole = {log() {}, warn() {}, error() {}};
const context = {exports: {}, require, setTimeout, console: silentConsole, window: {}};
vm.runInNewContext(compiled, context, {filename: parserPath});
const {CppCodeExecutor, validateCppSyntax} = context.exports;
const main = body => `int main() {\n${body}\n}`;
// Complete program from the first email screenshot; the second repeats this issue.
const customerEmailCode = `void test() {
    for (int i = 0; i < 2; i++) {
    }
}

int main() {
    // 在这里编写你的C++代码来控制角色
    turnLeft(-1);
    for (int i = 0; i < 1; i++) {
        test();
        playerMove(i);
    }
    return 0;
}`;
// The third screenshot reports cout without supplying a cout example.
// Add observable output to the supplied program to check both fixes together.
const customerEmailWithOutput = customerEmailCode.replace('        playerMove(i);',
    '        cout << "i=" << i << endl;\n        playerMove(i);');

async function run(code, expected, configure) {
    const moves = [];
    const turns = [];
    const output = [];
    context.window = {isScriptRunOver: false, cppGameAPI: {
        playerMove: async n => moves.push(n),
        turnLeft: async n => turns.push(n),
        cmdPrint: text => output.push(text)
    }};
    const executor = new CppCodeExecutor(code, null);
    if (configure) configure(executor, context.window);
    const validation = await validateCppSyntax(code);
    assert.strictEqual(validation.isValid, true, JSON.stringify(validation.errors));
    await executor.run();
    if (expected.moves) assert.deepStrictEqual(moves, expected.moves);
    if (expected.turns) assert.deepStrictEqual(turns, expected.turns);
    if (expected.output) assert.deepStrictEqual(output, expected.output);
    assert.strictEqual(executor.variables, executor.globalVariables, 'scope must unwind after execution');
    assert.strictEqual(executor.callStack.length, 0);
    return executor;
}

const cases = [
    ['customer email complete program (screenshots 1 and 2)', customerEmailCode, {moves: [0], turns: [-1]}],
    ['customer email with variable output (screenshot 3)', customerEmailWithOutput, {moves: [0], turns: [-1], output: ['i=0\n']}],
    ['nested loops', main('for (int i = 0; i < 2; i++) {\nfor (int i = 0; i < 2; i++) {\n}\nplayerMove(i);\n}'), {moves: [0, 1]}],
    ['loop initializer restores shadowed value', main('int i = 9;\nfor (int i = 0; i < 2; i++) {\n}\nplayerMove(i);'), {moves: [9]}],
    ['loop assignment updates existing value', main('int i = 9;\nfor (i = 0; i < 2; i++) {\n}\nplayerMove(i);'), {moves: [2]}],
    ['block declaration versus assignment', main('int n = 1;\nif (true) {\nint n = 7;\nplayerMove(n);\n}\nif (true) {\nn = 3;\n}\nplayerMove(n);'), {moves: [7, 3]}],
    ['string block shadowing', main('string msg = "outer";\nif (true) {\nstring msg = "C++";\ncout << msg;\n}\ncout << msg;'), {output: ['C++', 'outer']}],
    ['for body scope per iteration', main('int x = 9;\nfor (int i = 0; i < 2; i++) {\nplayerMove(x);\nint x = 2;\n}\nplayerMove(x);'), {moves: [9, 9, 9]}],
    ['while body scope per iteration', main('int x = 9;\nint i = 0;\nwhile (i < 2) {\nplayerMove(x);\nint x = 2;\ni++;\n}\nplayerMove(x);'), {moves: [9, 9, 9]}],
    ['function locals', 'void f() {\nint n = 7;\nplayerMove(n);\n}\n' + main('int n = 2;\nf();\nplayerMove(n);'), {moves: [7, 2]}],
    ['all arguments evaluated before binding', 'void f(int a, int b) {\nplayerMove(a);\nplayerMove(b);\n}\n' + main('int a = 2;\nf(7, a);\nplayerMove(a);'), {moves: [7, 2, 2]}],
    ['recursive locals and parameters', 'void f(int n) {\nint saved = n;\nif (n > 0) {\nf(n - 1);\n}\nplayerMove(saved);\n}\n' + main('f(2);'), {moves: [0, 1, 2]}],
    ['early void return unwinds scope', 'void f() {\nint n = 8;\nreturn;\n}\n' + main('int n = 2;\nf();\nplayerMove(n);'), {moves: [2]}],
    ['continue unwinds body scope', main('int x = 9;\nfor (int i = 0; i < 2; i++) {\nint x = 2;\ncontinue;\n}\nplayerMove(x);'), {moves: [9]}],
    ['break does not increment', main('int i = 0;\nfor (i = 0; i < 2; i++) {\nbreak;\n}\nplayerMove(i);'), {moves: [0]}],
    ['cout with equals', main('int i = 7;\ncout << "i=" << i << endl;'), {output: ['i=7\n']}],
    ['cout with operator text', main('cout << "value=42 C++ -- +=" << endl;'), {output: ['value=42 C++ -- +=\n']}],
    ['cout with game API text', main('cout << "playerMove(2)" << endl;'), {moves: [], output: ['playerMove(2)\n']}],
    ['qualified cout', main('std::cout << "Hello" << std::endl;'), {output: ['Hello\n']}],
    ['cout postfix and prefix', main('int i = 0;\ncout << i++ << endl;\ncout << ++i << endl;\ncout << i-- << endl;\ncout << --i << endl;'), {output: ['0\n', '2\n', '2\n', '0\n']}],
    ['cout arithmetic', main('int i = 3;\ncout << "result=" << (i * 2 + 1) << endl;'), {output: ['result=7\n']}],
    ['escaped quotes and stream delimiters', main(String.raw`cout << "a\"<<b\nC++" << endl;`), {output: ['a"<<b\nC++\n']}],
    ['consecutive output fragments', main('cout << "A";\ncout << "B" << endl;'), {output: ['A', 'B\n']}]
];

(async () => {
    for (const [name, code, expected] of cases) {
        try { await run(code, expected); } catch (error) {error.message = `${name}: ${error.message}`; throw error;}
        console.log(`PASS ${name}`);
    }
    // Seed the interpreter's global environment to verify lexical lookup and writes.
    const globalExecutor = await run('void f() {\ng += 1;\nplayerMove(g);\n}\n' + main('int g = 9;\nf();\nplayerMove(g);'), {moves: [2, 9]}, executor => executor.variables.set('g', 1));
    assert.strictEqual(globalExecutor.variables.get('g'), 2);
    console.log('PASS global writes survive function calls; caller locals are not visible');

    for (const stop of [false, true]) {
        const executor = new CppCodeExecutor('void f(int n) {\nfor (int i = 0; i < 2; i++) {\nplayerMove(i);\n}\n}\n' + main('f(2);'), null);
        executor.variables.set('n', 9);
        context.window = {isScriptRunOver: false, cppGameAPI: {playerMove: async () => {
            if (stop) context.window.isScriptRunOver = true;
            else throw new Error('game failure');
        }}};
        if (stop) await executor.run();
        else await assert.rejects(executor.run(), /game failure/);
        assert.strictEqual(executor.variables, executor.globalVariables);
        assert.strictEqual(executor.variables.get('n'), 9);
        assert.strictEqual(executor.variables.has('i'), false);
        assert.strictEqual(executor.callStack.length, 0);
        assert.strictEqual(executor.currentExecutionContext, null);
        console.log(`PASS scope cleanup on ${stop ? 'stop' : 'error'}`);
    }

    // Extract the actual React component callback, avoiding a game-engine dependency.
    const uiPath = path.resolve(__dirname, '../src/components/stage-cpp/stage-cpp-clang.jsx');
    const uiSource = fs.readFileSync(uiPath, 'utf8');
    const ast = babel.parseSync(uiSource, {configFile: false, babelrc: false, parserOpts: {plugins: ['jsx']}});
    let callback;
    function visit(node) {
        if (!node || typeof node !== 'object') return;
        if (node.type === 'ObjectProperty' && node.key.name === 'cmdPrint') callback = node.value;
        for (const value of Object.values(node)) {
            if (Array.isArray(value)) value.forEach(visit);
            else if (value && typeof value === 'object') visit(value);
        }
    }
    visit(ast);
    assert(callback, 'cmdPrint callback exists');
    for (const engineState of ['absent', 'ready', 'throwing']) {
        let displayed = '';
        const sent = [];
        const window = {};
        if (engineState !== 'absent') window.unityInstance = {SendMessage: (...args) => {
            if (engineState === 'throwing') throw new Error('engine unavailable');
            sent.push(args);
        }};
        const cmdPrint = vm.runInNewContext(`(${uiSource.slice(callback.start, callback.end)})`, {
            window, console: silentConsole, setCompilationOutput: update => {displayed = update(displayed);}
        });
        cmdPrint('A');
        cmdPrint('B\n');
        assert.strictEqual(displayed, 'AB\n');
        assert.strictEqual(window.cmd_print_text, 'AB\n');
        if (engineState === 'ready') assert.deepStrictEqual(sent[1], ['UIMain', 'SetText', 'AB\n']);
        console.log(`PASS output callback with ${engineState} engine`);

        // Connect the real interpreter to the real UI callback, including repeated runs.
        for (let attempt = 0; attempt < 2; attempt++) {
            displayed = '';
            window.cmd_print_text = '';
            await run(customerEmailWithOutput, {moves: [0], turns: [-1]}, (executor, runtimeWindow) => {
                runtimeWindow.cppGameAPI.cmdPrint = cmdPrint;
            });
            assert.strictEqual(displayed, 'i=0\n');
            assert.strictEqual(window.cmd_print_text, 'i=0\n');
            if (engineState === 'ready') assert.deepStrictEqual(sent[sent.length - 1], ['UIMain', 'SetText', 'i=0\n']);
        }
        console.log(`PASS customer program through output callback with ${engineState} engine`);
    }
    console.log(`${cases.length + 9} regression checks passed`);
})().catch(error => {console.error(error); process.exitCode = 1;});