/**

* Copyright (c) 2014-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/

import assert from “assert”; import { Emitter } from “./emit”; import { inherits } from “util”; import { getTypes } from “./util”;

function Entry() {

assert.ok(this instanceof Entry);

}

function FunctionEntry(returnLoc) {

Entry.call(this);
getTypes().assertLiteral(returnLoc);
this.returnLoc = returnLoc;

}

inherits(FunctionEntry, Entry); exports.FunctionEntry = FunctionEntry;

function LoopEntry(breakLoc, continueLoc, label) {

Entry.call(this);

const t = getTypes();

t.assertLiteral(breakLoc);
t.assertLiteral(continueLoc);

if (label) {
  t.assertIdentifier(label);
} else {
  label = null;
}

this.breakLoc = breakLoc;
this.continueLoc = continueLoc;
this.label = label;

}

inherits(LoopEntry, Entry); exports.LoopEntry = LoopEntry;

function SwitchEntry(breakLoc) {

Entry.call(this);
getTypes().assertLiteral(breakLoc);
this.breakLoc = breakLoc;

}

inherits(SwitchEntry, Entry); exports.SwitchEntry = SwitchEntry;

function TryEntry(firstLoc, catchEntry, finallyEntry) {

Entry.call(this);

const t = getTypes();
t.assertLiteral(firstLoc);

if (catchEntry) {
  assert.ok(catchEntry instanceof CatchEntry);
} else {
  catchEntry = null;
}

if (finallyEntry) {
  assert.ok(finallyEntry instanceof FinallyEntry);
} else {
  finallyEntry = null;
}

// Have to have one or the other (or both).
assert.ok(catchEntry || finallyEntry);

this.firstLoc = firstLoc;
this.catchEntry = catchEntry;
this.finallyEntry = finallyEntry;

}

inherits(TryEntry, Entry); exports.TryEntry = TryEntry;

function CatchEntry(firstLoc, paramId) {

Entry.call(this);

const t = getTypes();

t.assertLiteral(firstLoc);
t.assertIdentifier(paramId);

this.firstLoc = firstLoc;
this.paramId = paramId;

}

inherits(CatchEntry, Entry); exports.CatchEntry = CatchEntry;

function FinallyEntry(firstLoc, afterLoc) {

Entry.call(this);
const t = getTypes();
t.assertLiteral(firstLoc);
t.assertLiteral(afterLoc);
this.firstLoc = firstLoc;
this.afterLoc = afterLoc;

}

inherits(FinallyEntry, Entry); exports.FinallyEntry = FinallyEntry;

function LabeledEntry(breakLoc, label) {

Entry.call(this);

const t = getTypes();

t.assertLiteral(breakLoc);
t.assertIdentifier(label);

this.breakLoc = breakLoc;
this.label = label;

}

inherits(LabeledEntry, Entry); exports.LabeledEntry = LabeledEntry;

function LeapManager(emitter) {

assert.ok(this instanceof LeapManager);

assert.ok(emitter instanceof Emitter);

this.emitter = emitter;
this.entryStack = [new FunctionEntry(emitter.finalLoc)];

}

let LMp = LeapManager.prototype; exports.LeapManager = LeapManager;

LMp.withEntry = function(entry, callback) {

assert.ok(entry instanceof Entry);
this.entryStack.push(entry);
try {
  callback.call(this.emitter);
} finally {
  let popped = this.entryStack.pop();
  assert.strictEqual(popped, entry);
}

};

LMp._findLeapLocation = function(property, label) {

for (let i = this.entryStack.length - 1; i >= 0; --i) {
  let entry = this.entryStack[i];
  let loc = entry[property];
  if (loc) {
    if (label) {
      if (entry.label &&
          entry.label.name === label.name) {
        return loc;
      }
    } else if (entry instanceof LabeledEntry) {
      // Ignore LabeledEntry entries unless we are actually breaking to
      // a label.
    } else {
      return loc;
    }
  }
}

return null;

};

LMp.getBreakLoc = function(label) {

return this._findLeapLocation("breakLoc", label);

};

LMp.getContinueLoc = function(label) {

return this._findLeapLocation("continueLoc", label);

};