// writes the language server's javascript image: build/js/lsp.bin, the server's
// genome (build/lsp/lsp_genome.bin, made by src/tools/mklsp.sh), and
// build/js/lsp.json, the map it was built for, read from build/lsp/memmap.h. the
// vm needs the layout, because the server's map is not the compiler's. the image
// is generated, so it goes to build/js/ and nothing is left in the tree.
//
//   node src/js/extract_lsp.js [--lsp DIR] [--out DIR]
//
// build the lsp first (`make lsp`, or src/tools/mklsp.sh).
const fs = require('fs');
const path = require('path');
const root = path.join(__dirname, '..', '..');

const args = process.argv.slice(2);
if (args.includes('--help') || args.includes('-h')) {
    console.log([
        'usage: node src/js/extract_lsp.js [--lsp DIR] [--out DIR]',
        'copies the language server genome beside a json description of its memory map.',
        'options:',
        '  --lsp DIR    the language server build to read; defaults to build/lsp',
        '  --out DIR    where to write lsp.bin and lsp.json; defaults to build/js',
        '  --help, -h   show this help and exit',
    ].join('\n'));
    process.exit(0);
}
let out = path.join(root, 'build', 'js'), lsp = path.join(root, 'build', 'lsp');
for (let i = 0; i < args.length; i++) {
    if (args[i] === '--out' && args[i + 1]) out = args[++i];
    else if (args[i] === '--lsp' && args[i + 1]) lsp = args[++i];
    else {
        console.error('extract_lsp: unexpected arguments; use --help for usage');
        process.exit(2);
    }
}

const genomePath = path.join(lsp, 'lsp_genome.bin');
const mapPath = path.join(lsp, 'memmap.h');
if (!fs.existsSync(genomePath)) {
    console.error('extract_lsp: no language server image at ' + genomePath + '; run `make lsp` first');
    process.exit(1);
}
const { mapValues } = require('./mapvalues.js');
const layout = mapValues(mapPath, ['GORG', 'DS0', 'DSLIM', 'RS0', 'RSLIM', 'SYSGATE', 'ZFP', 'HEAP_LO', 'HEAP_HI']);
const image = fs.readFileSync(genomePath);
if (image.length % 8) throw new Error(genomePath + ' is not a whole number of words');
const glen = image.length / 8;

fs.mkdirSync(out, { recursive: true });
fs.copyFileSync(genomePath, path.join(out, 'lsp.bin'));
fs.writeFileSync(path.join(out, 'lsp.json'), JSON.stringify({ gorg: layout.GORG, glen, layout }));
console.log('wrote ' + path.relative(root, path.join(out, 'lsp.bin')) + ': genome ' + glen + ' words at ' + layout.GORG +
    ', heap ' + layout.HEAP_LO + '..' + layout.HEAP_HI);