'use strict';
// Tests zlib streams with truncated compressed input

const common = require('../common');
const assert = require('assert');
const zlib = require('zlib');

const inputString = 'ΩΩLorem ipsum dolor sit amet, consectetur adipiscing eli' +
                    't. Morbi faucibus, purus at gravida dictum, libero arcu ' +
                    'convallis lacus, in commodo libero metus eu nisi. Nullam' +
                    ' commodo, neque nec porta placerat, nisi est fermentum a' +
                    'ugue, vitae gravida tellus sapien sit amet tellus. Aenea' +
                    'n non diam orci. Proin quis elit turpis. Suspendisse non' +
                    ' diam ipsum. Suspendisse nec ullamcorper odio. Vestibulu' +
                    'm arcu mi, sodales non suscipit id, ultrices ut massa. S' +
                    'ed ac sem sit amet arcu malesuada fermentum. Nunc sed. ';

const errMessage = /unexpected end of file/;

[
  { comp: 'gzip', decomp: 'gunzip', decompSync: 'gunzipSync' },
  { comp: 'gzip', decomp: 'unzip', decompSync: 'unzipSync' },
  { comp: 'deflate', decomp: 'inflate', decompSync: 'inflateSync' },
  { comp: 'deflateRaw', decomp: 'inflateRaw', decompSync: 'inflateRawSync' },
  {
    comp: 'zstdCompress',
    decomp: 'zstdDecompress',
    decompSync: 'zstdDecompressSync',
    partialFlush: zlib.constants.ZSTD_e_flush,
  },
].forEach(function(methods) {
  zlib[methods.comp](inputString, common.mustSucceed((compressed) => {
    const truncated = compressed.slice(0, compressed.length / 2);
    const toUTF8 = (buffer) => buffer.toString('utf-8');

    // sync sanity
    const decompressed = zlib[methods.decompSync](compressed);
    assert.strictEqual(toUTF8(decompressed), inputString);

    // async sanity
    zlib[methods.decomp](compressed, common.mustSucceed((result) => {
      assert.strictEqual(toUTF8(result), inputString);
    }));

    // Sync truncated input test
    assert.throws(function() {
      zlib[methods.decompSync](truncated);
    }, errMessage);

    // Async truncated input test
    zlib[methods.decomp](truncated, common.mustCall((err) => {
      assert.match(err.message, errMessage);
    }));

    const partialFlushOpt = {
      finishFlush: methods.partialFlush ?? zlib.constants.Z_SYNC_FLUSH,
    };

    // Sync truncated input test with a non-finalizing finish flush.
    const result = toUTF8(zlib[methods.decompSync](truncated, partialFlushOpt));
    assert.strictEqual(result, inputString.slice(0, result.length));

    // Async truncated input test with a non-finalizing finish flush.
    zlib[methods.decomp](truncated, partialFlushOpt, common.mustSucceed((decompressed) => {
      const result = toUTF8(decompressed);
      assert.strictEqual(result, inputString.slice(0, result.length));
    }));
  }));
});

// A non-zero return from ZSTD_decompressStream() can also mean that the
// output buffer is full. Make sure that is drained before treating the return
// value as truncated input.
{
  const input = Buffer.alloc(zlib.constants.Z_DEFAULT_CHUNK * 2, 0x61);
  const compressed = zlib.zstdCompressSync(input);
  const decompressed = zlib.zstdDecompressSync(compressed, {
    chunkSize: zlib.constants.Z_MIN_CHUNK,
  });
  assert.deepStrictEqual(decompressed, input);
}

// Ending a stream after a previous write completed a frame must not be
// mistaken for an empty, truncated frame.
{
  const input = Buffer.from(inputString);
  const compressed = zlib.zstdCompressSync(input);
  const decompressor = zlib.createZstdDecompress();
  const output = [];

  decompressor.on('data', (chunk) => output.push(chunk));
  decompressor.on('end', common.mustCall(() => {
    assert.deepStrictEqual(Buffer.concat(output), input);
  }));
  decompressor.write(compressed, common.mustCall(() => decompressor.end()));
}

// Conversely, ending after a previous write supplied only part of a frame
// must report that the frame is incomplete.
{
  const compressed = zlib.zstdCompressSync(inputString);
  const truncated = compressed.subarray(0, compressed.length / 2);
  const decompressor = zlib.createZstdDecompress();

  decompressor.on('error', common.mustCall((error) => {
    assert.match(error.message, errMessage);
  }));
  decompressor.write(truncated, common.mustCall(() => decompressor.end()));
  decompressor.resume();
}
