/* global vm */
const {chromium} = require('playwright-chromium');
const test = require('tap').test;
const path = require('path');
const fs = require('fs');

const allGpuModes = ['ForceCPU', 'ForceGPU', 'Automatic'];

const indexHTML = path.resolve(__dirname, 'index.html');
const testDir = (...args) => path.resolve(__dirname, 'scratch-tests', ...args);

const checkOneGpuMode = (t, says) => {
    // Map string messages to tap reporting methods. This will be used
    // with events from scratch's runtime emitted on block instructions.
    let didPlan = false;
    let didEnd = false;
    const reporters = {
        comment (message) {
            t.comment(message);
        },
        pass (reason) {
            t.pass(reason);
        },
        fail (reason) {
            t.fail(reason);
        },
        plan (count) {
            didPlan = true;
            t.plan(Number(count));
        },
        end () {
            didEnd = true;
            t.end();
        }
    };

    // loop over each "SAY" we caught from the VM and use the reporters
    says.forEach(text => {
        // first word of the say is going to be a "command"
        const command = text.split(/\s+/, 1)[0].toLowerCase();
        if (reporters[command]) {
            return reporters[command](text.substring(command.length).trim());
        }

        // Default to a comment with the full text if we didn't match
        // any command prefix
        return reporters.comment(text);
    });

    if (!didPlan) {
        t.comment('did not say "plan NUMBER_OF_TESTS"');
    }

    // End must be called so that tap knows the test is done. If
    // the test has a SAY "end" block but that block did not
    // execute, this explicit failure will raise that issue so
    // it can be resolved.
    if (!didEnd) {
        t.fail('did not say "end"');
        t.end();
    }
};

const testFile = async (file, page) => {
    // start each test by going to the index.html, and loading the scratch file
    await page.goto(`file://${indexHTML}`);
    const fileInput = await page.$('#file');
    await fileInput.setInputFiles(testDir(file));
    await page.evaluate(() =>
        // `loadFile` is defined on the page itself.
        // eslint-disable-next-line no-undef
        loadFile()
    );
    const says = await page.evaluate(async useGpuModes => {
        // This function is run INSIDE the integration chrome browser via some
        // injection and .toString() magic.  We can return some "simple data"
        // back across as a promise, so we will just log all the says that happen
        // for parsing after.

        // this becomes the `says` in the outer scope
        const allMessages = {};
        const TIMEOUT = 5000;

        vm.runtime.on('SAY', (_, __, message) => {
            const messages = allMessages[vm.renderer._useGpuMode];
            messages.push(message);
        });

        for (const useGpuMode of useGpuModes) {
            const messages = allMessages[useGpuMode] = [];

            vm.renderer.setUseGpuMode(useGpuMode);
            vm.greenFlag();
            const startTime = Date.now();

            // wait for all threads to complete before moving on to the next mode
            while (vm.runtime.threads.some(thread => vm.runtime.isActiveThread(thread))) {
                if ((Date.now() - startTime) >= TIMEOUT) {
                    // if we push the message after end, the failure from tap is not very useful:
                    // "not ok test after end() was called"
                    messages.unshift(`fail Threads still running after ${TIMEOUT}ms`);
                    break;
                }

                await new Promise(resolve => setTimeout(resolve, 50));
            }
        }

        return allMessages;
    }, allGpuModes);

    for (const gpuMode of allGpuModes) {
        test(`File: ${file}, GPU Mode: ${gpuMode}`, t => checkOneGpuMode(t, says[gpuMode]));
    }
};

// immediately invoked async function to let us wait for each test to finish before starting the next.
(async () => {
    const browser = await chromium.launch();
    const page = await browser.newPage();

    const files = fs.readdirSync(testDir())
        .filter(uri => uri.endsWith('.sb2') || uri.endsWith('.sb3'));

    for (const file of files) {
        await testFile(file, page);
    }

    // close the browser window we used
    await browser.close();
})().catch(err => {
    // Handle promise rejections by exiting with a nonzero code to ensure that tests don't erroneously pass
    // eslint-disable-next-line no-console
    console.error(err.message);
    process.exit(1);
});