// (C) Copyright 2020 Nuxeo (http://nuxeo.com/) and others.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Contributors:
//     Florent Guillaume
// v1.0

// This script updates ancestors ids after a move.
// It is NOT a full move.

// ==========

// var DBNAME = "unittests";
// var COLLNAME = "test";
var DBNAME = "nuxeo"
var COLLNAME = "default"

var DOC_ID = "f77e10772dbbfa2a";
var DEST_FOLDER_ID = "e02a327272c681c2";

// ==========

db = db.getSiblingDB(DBNAME);
coll = db.getCollection(COLLNAME);
print();
print("Using " + DBNAME + "." + COLLNAME);


function check(expected, actual) {
  var e = JSON.stringify(expected);
  var a = JSON.stringify(actual);
  if (e != a) {
    print("FAIL expected=" + e + ", actual=" + a);
    quit(99);
  }
}


function name(id) {
  return coll.findOne({'ecm:id': id})['ecm:name'];
}

function path(id) {
  var doc = coll.findOne({'ecm:id': id});
  if (doc == null) return null;
  var aids = doc['ecm:ancestorIds'];
  if (aids == null) return '/';
  aids.push(id);
  return aids.map(i => name(i)).join('/');
}


function nuxeoToMongo(id) {
  if (id.length == 36) { // UUID
    return id;
  } else if (id.length == 16) { // hex long
    var top = parseInt(id.substring(0, 8), 16);
    var bottom = parseInt(id.substring(8, 16), 16);
    return NumberLong(0, top, bottom);
  } else {
    print("Bad length for id: " + id);
    quit(99);
  }
}

function mongoToNuxeo(id) {
  if (typeof id == 'string') {
    return id;
  } else if (id instanceof NumberLong) {
    var hex = id.bottom.toString(16);
    while (hex.length < 8) {
      hex = "0" + hex;
    }
    hex = id.top.toString(16) + hex
    while (hex.length < 16) {
      hex = "0" + hex;
    }
    return hex;
  } else {
    print("Bad id: " + id);
    quit(99);
  }
}

// check("12345678abcdabcd", mongoToNuxeo(nuxeoToMongo("12345678abcdabcd")));
// check("ff345678abcdabcd", mongoToNuxeo(nuxeoToMongo("ff345678abcdabcd")));
// check("003456780bcdabcd", mongoToNuxeo(nuxeoToMongo("003456780bcdabcd")));


function debugListAllPaths() {
  coll.find({}).forEach(doc => {
    var id = doc['ecm:id'];
    print(mongoToNuxeo(id) + " " + path(id));
  });
}

function same(a, b) {
  if (a instanceof NumberLong && b instanceof NumberLong) {
    return a.top == b.top && a.bottom == b.bottom;
  } else {
    return a === b;
  }
}

function computeUpdate(src_aids, src_id, dst_aids) {
  // print("src_aids=" + src_aids);
  // print("src_id=" + src_id);
  // print("dst_aids=" + dst_aids);
  var i = 0;
  while (true) {
    var a = src_aids[i];
    var b = dst_aids[i];
    // print("i=" + i + " a=" + a + " b=" + b);
    if (a === undefined && b === undefined) {
      // print("identical");
      return null;
    }
    if (b === undefined) {
      var del = src_aids.slice(i, 999);
      // print("del " + del);
      return {'del': del};
    }
    if (!same(a, b)) {
      if (same(b, src_id)) {
        print("FAIL cannot move under itself");
        return;
      }
      var del = src_aids.slice(i, 999);
      var ins = dst_aids.slice(i, 999);
      // print("del " + del + " ins " + ins);
      return {'del': del, 'ins': ins, 'pos': i};
    }
    // a == b, loop again
    i++;
  }
}

// check(null,                                             computeUpdate(['a','b','c','d','e'], 'f', ['a','b','c','d','e']));
// check({'del': ['e'], 'ins': ['i','j','k'], 'pos': 4},   computeUpdate(['a','b','c','d','e'], 'f', ['a','b','c','d','i','j','k']));
// check({'del': ['d','e']},                               computeUpdate(['a','b','c','d','e'], 'f', ['a','b','c']));
// check({'del': [], 'ins': ['ff'], 'pos': 5},             computeUpdate(['a','b','c','d','e'], 'f', ['a','b','c','d','e','ff']));
// check(undefined,                                        computeUpdate(['a','b','c','d','e'], 'f', ['a','b','c','d','e','f','g']));


// ==========

var doc_id = nuxeoToMongo(DOC_ID);
var dest_folder_id = nuxeoToMongo(DEST_FOLDER_ID);

print("Moving " + path(doc_id) + " under " + path(dest_folder_id));

var doc_aids = coll.findOne({'ecm:id': doc_id})['ecm:ancestorIds'];
var dest_aids = coll.findOne({'ecm:id': dest_folder_id})['ecm:ancestorIds'];
dest_aids.push(dest_folder_id);

var diff = computeUpdate(doc_aids, doc_id, dest_aids);
if (diff == null) {
  print("Nothing to change");
  quit(0);
}

var query = {$or: [{'ecm:ancestorIds': doc_id}, {'ecm:id': doc_id}]};
print("query");
printjson(query);
print("Counting docs to update...");
var n = coll.count(query);
print("Docs to update: " + n);

var del = diff['del'];
var ins = diff['ins'];
var pos = diff['pos'];
var update = {};
if (del.length != 0) {
  update['$pullAll'] = {'ecm:ancestorIds': del};
}
if (ins != undefined) {
  update['$push'] = {'ecm:ancestorIds': {$each: ins, $position: pos}};
}
print("update");
printjson(update);
print(Date() + " Starting ancestors replacement...");
coll.update(query, update, {multi: true});
print(Date() + " Done.");

// debugListAllPaths();