import json
import subprocess
from pathlib import Path


ROOT = Path(__file__).resolve().parents[2]


def test_large_edit_history_is_compressed_and_restores_independent_snapshots():
    script = r"""
const fs=require('node:fs'),vm=require('node:vm');
const context=vm.createContext({Response,Blob,CompressionStream,DecompressionStream,
  document:{addEventListener(){}},console});
vm.runInContext(fs.readFileSync(process.argv[1],'utf8')+';globalThis.app=EstApp',context);
(async()=>{
  const {app}=context;
  app.state.project={name:'before',binary:'x'.repeat(11*1024*1024)};
  app.remember();
  app.state.project.name='after';
  const entry=await app.state.history[0],restored=await app.restore(entry);
  if(!(entry instanceof Blob)||entry.size>=100000)throw Error('History is not compressed');
  if(restored.name!=='before'||restored.binary.length!==11*1024*1024)
    throw Error('Snapshot was changed or truncated');
  restored.name='independent';
  if((await app.restore(entry)).name!=='before')throw Error('Snapshot shares mutable data');
  app.state.project={name:'small'};
  app.state.future=['discard'];
  for(let i=0;i<10;i++){app.state.project.name=String(i);app.remember();}
  if(app.state.history.length!==8||app.state.future.length)throw Error('History limits');
  if((await app.restore(app.state.history[0])).name!=='2')throw Error('History ordering');
  context.CompressionStream=undefined;
  app.state.project={binary:'y'.repeat(11*1024*1024)};
  const fallback=app.snapshot();
  if(typeof fallback!=='string')throw Error('Missing platform fallback');
  if((await app.restore(fallback)).binary.length!==11*1024*1024)
    throw Error('Fallback truncated');
  console.log(JSON.stringify({compressedBytes:entry.size,revision:app.state.revision}));
})().catch(error=>{console.error(error);process.exitCode=1});
"""
    result = json.loads(
        subprocess.check_output(
            ["node", "-e", script, str(ROOT / "tools/est-test/native-app.js")],
            text=True,
            encoding="utf-8",
        )
    )
    assert result["compressedBytes"] < 100_000
    assert result["revision"] == 11