const assert = require('node:assert/strict');
const fs = require('node:fs');
const test = require('node:test');
const vm = require('node:vm');

const script = fs.readFileSync(
    new URL('../static/js/android-back-button.js', `file://${__filename}`),
    'utf8'
);

function createHarness({platform = 'android', pathname = '/', openDialog = false, openDetails = false} = {}) {
    const calls = [];
    const dialog = {close: () => calls.push('dialog.close')};
    const details = {open: true};
    const capacitor = {
        getPlatform: () => platform,
        addListener: (plugin, event, handler) => {
            calls.push(`listener:${plugin}:${event}`);
            capacitor.backHandler = handler;
            return {remove: async () => {}};
        },
        nativePromise: (plugin, method) => {
            calls.push(`${plugin}.${method}`);
            return Promise.resolve();
        }
    };

    vm.runInNewContext(script, {
        window: {Capacitor: capacitor},
        document: {
            querySelector: selector => selector === 'dialog[open]'
                ? (openDialog ? dialog : null)
                : (openDetails ? details : null)
        },
        location: {pathname, replace: path => calls.push(`replace:${path}`)},
        history: {back: () => calls.push('history.back')}
    });
    return {calls, capacitor, details};
}

test('Android back closes an open dialog or details panel first', () => {
    const dialog = createHarness({openDialog: true});
    dialog.capacitor.backHandler({canGoBack: true});
    assert.deepEqual(dialog.calls, ['listener:App:backButton', 'dialog.close']);

    const details = createHarness({openDetails: true});
    details.capacitor.backHandler({canGoBack: true});
    assert.equal(details.details.open, false);
    assert.deepEqual(details.calls, ['listener:App:backButton']);
});

test('Android back follows WebView history away from the start page', () => {
    const {calls, capacitor} = createHarness({pathname: '/messages'});
    capacitor.backHandler({canGoBack: true});
    assert.deepEqual(calls, ['listener:App:backButton', 'history.back']);
});

test('Android back returns to the start page when a deep link has no history', () => {
    const {calls, capacitor} = createHarness({pathname: '/messages/42'});
    capacitor.backHandler({canGoBack: false});
    assert.deepEqual(calls, ['listener:App:backButton', 'replace:/']);
});

test('Android back exits only from the start page', () => {
    const {calls, capacitor} = createHarness();
    capacitor.backHandler({canGoBack: false});
    assert.deepEqual(calls, ['listener:App:backButton', 'App.exitApp']);
});

test('web browsers do not register the native back handler', () => {
    const {calls} = createHarness({platform: 'web'});
    assert.deepEqual(calls, []);
});