/*
 * This is a debug tool. It checks all revisions for data corruption
 */

if (process.argv.length != 2) {
  console.error('Use: node bin/checkAllPads.js');
  process.exit(1);
}

// load and initialize NPM
const npm = require('../src/node_modules/npm');
npm.load({}, async () => {
  try {
    // initialize the database
    const settings = require('../src/node/utils/Settings');
    const db = require('../src/node/db/DB');
    await db.init();

    // load modules
    const Changeset = require('../src/static/js/Changeset');
    const padManager = require('../src/node/db/PadManager');

    // get all pads
    const res = await padManager.listAllPads();

    for (const padId of res.padIDs) {
      const pad = await padManager.getPad(padId);

      // check if the pad has a pool
      if (pad.pool === undefined) {
        console.error(`[${pad.id}] Missing attribute pool`);
        continue;
      }

      // create an array with key kevisions
      // key revisions always save the full pad atext
      const head = pad.getHeadRevisionNumber();
      const keyRevisions = [];
      for (let rev = 0; rev < head; rev += 100) {
        keyRevisions.push(rev);
      }

      // run through all key revisions
      for (const keyRev of keyRevisions) {
        // create an array of revisions we need till the next keyRevision or the End
        const revisionsNeeded = [];
        for (let rev = keyRev; rev <= keyRev + 100 && rev <= head; rev++) {
          revisionsNeeded.push(rev);
        }

        // this array will hold all revision changesets
        const revisions = [];

        // run through all needed revisions and get them from the database
        for (const revNum of revisionsNeeded) {
          const revision = await db.get(`pad:${pad.id}:revs:${revNum}`);
          revisions[revNum] = revision;
        }

        // check if the revision exists
        if (revisions[keyRev] == null) {
          console.error(`[${pad.id}] Missing revision ${keyRev}`);
          continue;
        }

        // check if there is a atext in the keyRevisions
        if (revisions[keyRev].meta === undefined || revisions[keyRev].meta.atext === undefined) {
          console.error(`[${pad.id}] Missing atext in revision ${keyRev}`);
          continue;
        }

        const apool = pad.pool;
        let atext = revisions[keyRev].meta.atext;

        for (let rev = keyRev + 1; rev <= keyRev + 100 && rev <= head; rev++) {
          try {
            const cs = revisions[rev].changeset;
            atext = Changeset.applyToAText(cs, atext, apool);
          } catch (e) {
            console.error(`[${pad.id}] Bad changeset at revision ${i} - ${e.message}`);
          }
        }
      }
      console.log('finished');
      process.exit(0);
    }
  } catch (err) {
    console.trace(err);
    process.exit(1);
  }
});