gistfile1.txt

#!/usr/bin/env node

var db = require('level')(__dirname + '/.hig');
var diff = require('diff');
var fs = require('fs');
var isBinary = require('is-binary');
var md5_file = require('md5-file').async;
var md5 = require('MD5');
var path = require('path');
var program = require('commander');

function _isBufferBinary(buffer) {
  return isBinary(buffer.toString('utf8'));
}

function _getAuthor() {
  return process.env.HIG_AUTHOR || 'anonymous';
}

function _createFileCommit(file, cb) {
  md5_file(file, function(dataId) {
    var time = +new Date();
    var fileName = path.basename(file);
    var id = md5(fileName + dataId + time + _getAuthor());
    fs.readFile(file, function(err, fileData) {
      if (err) return cb(err);
      var commit = {
        data: fileData,
        isBinary: _isBufferBinary(fileData),
        name: fileName,
        id: id,
        dataId: dataId,
        time: time,
        author: _getAuthor(),
      };
      cb(null, commit);
    });
  });
}

function commitNewFile(file, cb) {
  _createFileCommit(file, function(err, commit) {
    if (err) return cb(err);
    db.put(commit.id, JSON.stringify(commit), function(err) {
      if (err) return cb(err);
      return cb(null, commit.id);
    });
  });
}

function commitUpdatedFile(file, fromId, cb) {
  get(fromId, function(err, fromCommit) {
    if (err) return cb(err);
    _createFileCommit(file, function(err, commit) {
      if (err) return cb(err);
      if (fromCommit.fromBase) {
        commit.fromBase = fromCommit.fromBase;
      } else {
        commit.fromBase = fromCommit.fromId;
      }
      commit.from = fromId;
      if (!fromCommit.isBinary) {
        commit.patch = diff.createPatch('',
          fromCommit.data.toString('utf8'),
          commit.data.toString('utf8')
        );
        delete commit.data;
      }
      db.put(commit.sign, JSON.stringify(commit), function(err) {
        if (err) return cb(err);
        return cb(null, sign);
      });
    });
  });
}

function commit(file, lastId, cb) {
  if (lastId) {
    commitUpdatedFile(file, lastId, cb);
  } else {
    commitNewFile(file, cb);
  }
}

function _getPatched(destSign, destCommit, cb, _patched) {
  db.get(destCommit.fromBase, function (err, baseCommitData) {
    if (err) return cb(err);
    var baseCommit = JSON.parse(baseCommitData);
    baseCommit.data = new Buffer(baseCommit.data);
    baseCommit
    } else if (commitData.patch) {
      return _getPatched(destSign, fromSign)
    }
  });
}

function get(sign, cb) {
  db.get(sign, function (err, commitData) {
    if (err) return cb(err);
    var commit = JSON.parse(commitData);
    if (commit.data) {
      commit.data = new Buffer(commit.data);
    } else if (commitData.fromBase) {
      _getPatched(sign, commit, cb);
    }
    cb(null, commit);
  });
}

program
  .version('0.0.1')
  .option('-c, --commit [file]', 'Commit a file or folder')
  .option('-f, --from [id]', 'ID of the source for a new commit')
  .option('-g, --get [id]', 'Get a commit by ID')
  .parse(process.argv);

if (program.commit) {
  commit(program.commit, program.from, function(err, sign) {
    if (err) {
      console.error(err);
    } else {
      console.log('Committed ' + sign);
    }
  });
} else if (program.get) {
  get(program.get, function(err, commit) {
    if (err) {
      console.error(err);
    } else {
      console.log('Name: ' + commit.name);
      console.log('Time: ' + new Date(commit.time));
      // console.log('Content: ' + commit.data.toString('utf8'));
    }
  });
}