const { readFileSync, writeFileSync } = require('fs');

function read (filename) {
    const txt = readFileSync(filename, 'utf8')
        .replace(/\r/gm, '')
        .replace(/\n/gm, '«')
        .replace(/\/\*.*?\*\//gm, '')
        .replace(/«/gm, '\n')
        .replace(/\s+\/\/.*/g, '');
    return JSON.parse(txt);
}

const packageList = {};
const rush = read(`${__dirname}/../rush.json`);
const pjs = {};

function writeIfChanged (filename, content) {
    const orig = JSON.parse(readFileSync(filename));
    const origJson = JSON.stringify(orig, null, 2);
    const json = JSON.stringify(content, null, 2);

    if (origJson !== json) {
        console.log(`Writing updated file '${filename}'`);
        writeFileSync(filename, json);
        return true;
    }
    return false;
}

function versionToInt (ver) {
    const v = ver.replace(/[^\d\.]/g, '').split('.').slice(0, 3);
    while (v.length < 3) {
        v.unshift(0);
    }
    let n = 0;
    for (let i = 0; i < v.length; i++) {
        n = n + ((2 ** (i * 16)) * parseInt(v[v.length - 1 - i]));
    }
    return n;
}

function setPeerDependencies (dependencies) {
    for (const dep in dependencies) {
        const ref = pjs[dep];
        if (ref) {
            if (dependencies[dep] !== `~${ref.version}`) {
                console.log(`updating peer depedency ${dep} to ~${ref.version}`);
                dependencies[dep] = `~${ref.version}`;
            }
        }
    }
}

function recordDeps (dependencies) {
    for (const packageName in dependencies) {
        const packageVersion = dependencies[packageName];
        if (packageList[packageName]) {
            // same version?
            if (packageList[packageName] === packageVersion) {
                continue;
            }
            console.log(`${packageName} has ['${packageList[packageName]}','${packageVersion}']`);

            // pick the higher one
            const v = versionToInt(packageVersion);

            if (v === 0) {
                console.error(`Unparsed version ${packageName}:${packageVersion}`);
                process.exit(1);
            }
            const v2 = versionToInt(packageList[packageName]);
            if (v > v2) {
                packageList[packageName] = packageVersion;
            }
        } else {
            packageList[packageName] = packageVersion;
        }
    }
}
function fixDeps (pj, dependencies) {
    for (const packageName in dependencies) {
        if (dependencies[packageName] !== packageList[packageName]) {
            console.log(`updating ${pj}:${packageName} from '${dependencies[packageName]}' to '${packageList[packageName]}'`);
            dependencies[packageName] = packageList[packageName];
        }
    }
}

// load all the projects
for (const each of rush.projects) {
    const packageName = each.packageName;
    const projectFolder = each.projectFolder;
    pjs[packageName] = JSON.parse(readFileSync(`${__dirname}/../${projectFolder}/package.json`));
}

// verify that peer dependencies are the same version as they are building.
for (const pj of Object.getOwnPropertyNames(pjs)) {
    const each = pjs[pj];
    setPeerDependencies(each.dependencies);
    setPeerDependencies(each.devDependencies);
    if (each['static-link']) {
        setPeerDependencies(each['static-link'].dependencies);
    }
}

// now compare to see if someone has an exnternal package with different version
// than everyone else.
for (const pj of Object.getOwnPropertyNames(pjs)) {
    const each = pjs[pj];
    recordDeps(each.dependencies);
    recordDeps(each.devDependencies);
    if (each['static-link']) {
        recordDeps(each['static-link'].dependencies);
    }
}

for (const pj of Object.getOwnPropertyNames(pjs)) {
    const each = pjs[pj];
    fixDeps(pj, each.dependencies);
    fixDeps(pj, each.devDependencies);
    if (each['static-link']) {
        fixDeps(pj, each['static-link'].dependencies);
    }
}
let changed = 0;

// write out the results.
for (const each of rush.projects) {
    const packageName = each.packageName;
    const projectFolder = each.projectFolder;
    if (writeIfChanged(`${__dirname}/../${projectFolder}/package.json`, pjs[packageName])) {
        changed++;
    }
}

if (changed) {
    console.log(`Updated ${changed} files.`);
} else {
    console.log('No changes made');
}