"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _path = require("./path");

var t = require("@babel/types");

const testing = process.env.NODE_ENV === "test";

class TraversalContext {
  constructor(scope, opts, state, parentPath) {
    this.queue = null;
    this.priorityQueue = null;
    this.parentPath = parentPath;
    this.scope = scope;
    this.state = state;
    this.opts = opts;
  }

  shouldVisit(node) {
    const opts = this.opts;
    if (opts.enter || opts.exit) return true;
    if (opts[node.type]) return true;
    const keys = t.VISITOR_KEYS[node.type];
    if (!(keys != null && keys.length)) return false;

    for (const key of keys) {
      if (node[key]) return true;
    }

    return false;
  }

  create(node, obj, key, listKey) {
    return _path.default.get({
      parentPath: this.parentPath,
      parent: node,
      container: obj,
      key: key,
      listKey
    });
  }

  maybeQueue(path, notPriority) {
    if (this.trap) {
      throw new Error("Infinite cycle detected");
    }

    if (this.queue) {
      if (notPriority) {
        this.queue.push(path);
      } else {
        this.priorityQueue.push(path);
      }
    }
  }

  visitMultiple(container, parent, listKey) {
    if (container.length === 0) return false;
    const queue = [];

    for (let key = 0; key < container.length; key++) {
      const node = container[key];

      if (node && this.shouldVisit(node)) {
        queue.push(this.create(parent, container, key, listKey));
      }
    }

    return this.visitQueue(queue);
  }

  visitSingle(node, key) {
    if (this.shouldVisit(node[key])) {
      return this.visitQueue([this.create(node, node, key)]);
    } else {
      return false;
    }
  }

  visitQueue(queue) {
    this.queue = queue;
    this.priorityQueue = [];
    const visited = new WeakSet();
    let stop = false;

    for (const path of queue) {
      path.resync();

      if (path.contexts.length === 0 || path.contexts[path.contexts.length - 1] !== this) {
        path.pushContext(this);
      }

      if (path.key === null) continue;

      if (testing && queue.length >= 10000) {
        this.trap = true;
      }

      const {
        node
      } = path;
      if (visited.has(node)) continue;
      if (node) visited.add(node);

      if (path.visit()) {
        stop = true;
        break;
      }

      if (this.priorityQueue.length) {
        stop = this.visitQueue(this.priorityQueue);
        this.priorityQueue = [];
        this.queue = queue;
        if (stop) break;
      }
    }

    for (const path of queue) {
      path.popContext();
    }

    this.queue = null;
    return stop;
  }

  visit(node, key) {
    const nodes = node[key];
    if (!nodes) return false;

    if (Array.isArray(nodes)) {
      return this.visitMultiple(nodes, node, key);
    } else {
      return this.visitSingle(node, key);
    }
  }

}

exports.default = TraversalContext;