xstate/lib/stateUtils.js

Finite State Machines and Statecharts for the Modern Web.

'use strict';

Object.defineProperty(exports, '__esModule', { value: true });

var _tslib = require('./_virtual/_tslib.js');
var utils = require('./utils.js');

var isLeafNode = function (stateNode) {
  return stateNode.type === 'atomic' || stateNode.type === 'final';
};
function getAllChildren(stateNode) {
  return Object.keys(stateNode.states).map(function (key) {
    return stateNode.states[key];
  });
}
function getChildren(stateNode) {
  return getAllChildren(stateNode).filter(function (sn) {
    return sn.type !== 'history';
  });
}
function getAllStateNodes(stateNode) {
  var stateNodes = [stateNode];

  if (isLeafNode(stateNode)) {
    return stateNodes;
  }

  return stateNodes.concat(utils.flatten(getChildren(stateNode).map(getAllStateNodes)));
}
function getConfiguration(prevStateNodes, stateNodes) {
  var e_1, _a, e_2, _b, e_3, _c, e_4, _d;

  var prevConfiguration = new Set(prevStateNodes);
  var prevAdjList = getAdjList(prevConfiguration);
  var configuration = new Set(stateNodes);

  try {
    // add all ancestors
    for (var configuration_1 = _tslib.__values(configuration), configuration_1_1 = configuration_1.next(); !configuration_1_1.done; configuration_1_1 = configuration_1.next()) {
      var s = configuration_1_1.value;
      var m = s.parent;

      while (m && !configuration.has(m)) {
        configuration.add(m);
        m = m.parent;
      }
    }
  } catch (e_1_1) {
    e_1 = {
      error: e_1_1
    };
  } finally {
    try {
      if (configuration_1_1 && !configuration_1_1.done && (_a = configuration_1.return)) _a.call(configuration_1);
    } finally {
      if (e_1) throw e_1.error;
    }
  }

  var adjList = getAdjList(configuration);

  try {
    // add descendants
    for (var configuration_2 = _tslib.__values(configuration), configuration_2_1 = configuration_2.next(); !configuration_2_1.done; configuration_2_1 = configuration_2.next()) {
      var s = configuration_2_1.value; // if previously active, add existing child nodes

      if (s.type === 'compound' && (!adjList.get(s) || !adjList.get(s).length)) {
        if (prevAdjList.get(s)) {
          prevAdjList.get(s).forEach(function (sn) {
            return configuration.add(sn);
          });
        } else {
          s.initialStateNodes.forEach(function (sn) {
            return configuration.add(sn);
          });
        }
      } else {
        if (s.type === 'parallel') {
          try {
            for (var _e = (e_3 = void 0, _tslib.__values(getChildren(s))), _f = _e.next(); !_f.done; _f = _e.next()) {
              var child = _f.value;

              if (!configuration.has(child)) {
                configuration.add(child);

                if (prevAdjList.get(child)) {
                  prevAdjList.get(child).forEach(function (sn) {
                    return configuration.add(sn);
                  });
                } else {
                  child.initialStateNodes.forEach(function (sn) {
                    return configuration.add(sn);
                  });
                }
              }
            }
          } catch (e_3_1) {
            e_3 = {
              error: e_3_1
            };
          } finally {
            try {
              if (_f && !_f.done && (_c = _e.return)) _c.call(_e);
            } finally {
              if (e_3) throw e_3.error;
            }
          }
        }
      }
    }
  } catch (e_2_1) {
    e_2 = {
      error: e_2_1
    };
  } finally {
    try {
      if (configuration_2_1 && !configuration_2_1.done && (_b = configuration_2.return)) _b.call(configuration_2);
    } finally {
      if (e_2) throw e_2.error;
    }
  }

  try {
    // add all ancestors
    for (var configuration_3 = _tslib.__values(configuration), configuration_3_1 = configuration_3.next(); !configuration_3_1.done; configuration_3_1 = configuration_3.next()) {
      var s = configuration_3_1.value;
      var m = s.parent;

      while (m && !configuration.has(m)) {
        configuration.add(m);
        m = m.parent;
      }
    }
  } catch (e_4_1) {
    e_4 = {
      error: e_4_1
    };
  } finally {
    try {
      if (configuration_3_1 && !configuration_3_1.done && (_d = configuration_3.return)) _d.call(configuration_3);
    } finally {
      if (e_4) throw e_4.error;
    }
  }

  return configuration;
}

function getValueFromAdj(baseNode, adjList) {
  var childStateNodes = adjList.get(baseNode);

  if (!childStateNodes) {
    return {}; // todo: fix?
  }

  if (baseNode.type === 'compound') {
    var childStateNode = childStateNodes[0];

    if (childStateNode) {
      if (isLeafNode(childStateNode)) {
        return childStateNode.key;
      }
    } else {
      return {};
    }
  }

  var stateValue = {};
  childStateNodes.forEach(function (csn) {
    stateValue[csn.key] = getValueFromAdj(csn, adjList);
  });
  return stateValue;
}

function getAdjList(configuration) {
  var e_5, _a;

  var adjList = new Map();

  try {
    for (var configuration_4 = _tslib.__values(configuration), configuration_4_1 = configuration_4.next(); !configuration_4_1.done; configuration_4_1 = configuration_4.next()) {
      var s = configuration_4_1.value;

      if (!adjList.has(s)) {
        adjList.set(s, []);
      }

      if (s.parent) {
        if (!adjList.has(s.parent)) {
          adjList.set(s.parent, []);
        }

        adjList.get(s.parent).push(s);
      }
    }
  } catch (e_5_1) {
    e_5 = {
      error: e_5_1
    };
  } finally {
    try {
      if (configuration_4_1 && !configuration_4_1.done && (_a = configuration_4.return)) _a.call(configuration_4);
    } finally {
      if (e_5) throw e_5.error;
    }
  }

  return adjList;
}
function getValue(rootNode, configuration) {
  var config = getConfiguration([rootNode], configuration);
  return getValueFromAdj(rootNode, getAdjList(config));
}
function has(iterable, item) {
  if (Array.isArray(iterable)) {
    return iterable.some(function (member) {
      return member === item;
    });
  }

  if (iterable instanceof Set) {
    return iterable.has(item);
  }

  return false; // TODO: fix
}
function nextEvents(configuration) {
  return _tslib.__spreadArray([], _tslib.__read(new Set(utils.flatten(_tslib.__spreadArray([], _tslib.__read(configuration.map(function (sn) {
    return sn.ownEvents;
  })), false)))), false);
}
function isInFinalState(configuration, stateNode) {
  if (stateNode.type === 'compound') {
    return getChildren(stateNode).some(function (s) {
      return s.type === 'final' && has(configuration, s);
    });
  }

  if (stateNode.type === 'parallel') {
    return getChildren(stateNode).every(function (sn) {
      return isInFinalState(configuration, sn);
    });
  }

  return false;
}
function getMeta(configuration) {
  if (configuration === void 0) {
    configuration = [];
  }

  return configuration.reduce(function (acc, stateNode) {
    if (stateNode.meta !== undefined) {
      acc[stateNode.id] = stateNode.meta;
    }

    return acc;
  }, {});
}
function getTagsFromConfiguration(configuration) {
  return new Set(utils.flatten(configuration.map(function (sn) {
    return sn.tags;
  })));
}

exports.getAdjList = getAdjList;
exports.getAllChildren = getAllChildren;
exports.getAllStateNodes = getAllStateNodes;
exports.getChildren = getChildren;
exports.getConfiguration = getConfiguration;
exports.getMeta = getMeta;
exports.getTagsFromConfiguration = getTagsFromConfiguration;
exports.getValue = getValue;
exports.has = has;
exports.isInFinalState = isInFinalState;
exports.isLeafNode = isLeafNode;
exports.nextEvents = nextEvents;