'use strict';

// Imports
const fs = require('fs');

// Get branch and project name from command line arguments.
const [, , limitFile, project, branch, commit] = process.argv;

// Load sizes.
const currentSizes = JSON.parse(fs.readFileSync('/tmp/current.log', 'utf8'));
const allLimitSizes = JSON.parse(fs.readFileSync(limitFile, 'utf8'));
const limitSizes = allLimitSizes[project][branch] || allLimitSizes[project]['master'];

// Check current sizes against limits.
let failed = false;
const successMessages = [];
const failureMessages = [];
for (const compressionType in limitSizes) {
  if (typeof limitSizes[compressionType] === 'object') {
    const limitPerFile = limitSizes[compressionType];

    for (const filename in limitPerFile) {
      const expectedSize = limitPerFile[filename];
      const actualSize = currentSizes[`${compressionType}/${filename}`];

      if (actualSize === undefined) {
        failed = true;
        // An expected compression type/file combination is missing. Maybe the file was renamed or
        // removed. Report it as an error, so the user updates the corresponding limit file.
        console.log(
            `ERROR: Commit ${commit} ${compressionType} ${filename} measurement is missing. ` +
            'Maybe the file was renamed or removed.');
      } else {
        const absoluteSizeDiff = Math.abs(actualSize - expectedSize);
        // If size diff is larger than 1% or 500 bytes...
        if (absoluteSizeDiff > 500 || absoluteSizeDiff > expectedSize / 100) {
          failed = true;
          // We must also catch when the size is significantly lower than the payload limit, so
          // we are forced to update the expected payload number when the payload size reduces.
          // Otherwise, we won't be able to catch future regressions that happen to be below
          // the artificially inflated limit.
          const operator = actualSize > expectedSize ? 'exceeded' : 'fell below';

          failureMessages.push(
            `FAIL: Commit ${commit} ${compressionType} ${filename} ${operator} expected size by 500 bytes or >1% ` +
            `(expected: ${expectedSize}, actual: ${actualSize}).`);
        } else {
          successMessages.push(`SUCCESS: Commit ${commit} ${compressionType} ${filename} did NOT cross size threshold of 500 bytes or >1% ` +
            `(expected: ${expectedSize}, actual: ${actualSize}).`);
        }
      }
    }
  }
}

// Group failure messages separately from success messages so they are easier to find.
successMessages.concat(failureMessages).forEach(message => console.log(message));

if (failed) {
  console.log(`If this is a desired change, please update the size limits in file '${limitFile}'.`);
  process.exit(1);
} else {
  console.log(`Payload size check passed. All diffs are less than 1% or 500 bytes.`);
}