import { Readable } from 'stream';

function _defineProperty(obj, key, value) {
  if (key in obj) {
    Object.defineProperty(obj, key, {
      value: value,
      enumerable: true,
      configurable: true,
      writable: true
    });
  } else {
    obj[key] = value;
  }

  return obj;
}

var _global, _global$JSON;

const rxEscapable = /[\\"\u0000-\u001f\u007f-\u009f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g; // table of character substitutions

const meta = {
  '\b': '\\b',
  '\t': '\\t',
  '\n': '\\n',
  '\f': '\\f',
  '\r': '\\r',
  '"': '\\"',
  '\\': '\\\\'
};

function isReadableStream(value) {
  return typeof value.read === 'function' && typeof value.pause === 'function' && typeof value.resume === 'function' && typeof value.pipe === 'function' && typeof value.once === 'function' && typeof value.removeListener === 'function';
}

var Types;

(function (Types) {
  Types[Types["Array"] = 0] = "Array";
  Types[Types["Object"] = 1] = "Object";
  Types[Types["ReadableString"] = 2] = "ReadableString";
  Types[Types["ReadableObject"] = 3] = "ReadableObject";
  Types[Types["Primitive"] = 4] = "Primitive";
  Types[Types["Promise"] = 5] = "Promise";
})(Types || (Types = {}));

function getType(value) {
  if (!value) return Types.Primitive;
  if (typeof value.then === 'function') return Types.Promise;
  if (isReadableStream(value)) return value._readableState.objectMode ? Types.ReadableObject : Types.ReadableString;
  if (Array.isArray(value)) return Types.Array;
  if (typeof value === 'object' || value instanceof Object) return Types.Object;
  return Types.Primitive;
}

function escapeString(string) {
  // Modified code, original code by Douglas Crockford
  // Original: https://github.com/douglascrockford/JSON-js/blob/master/json2.js
  // If the string contains no control characters, no quote characters, and no
  // backslash characters, then we can safely slap some quotes around it.
  // Otherwise we must also replace the offending characters with safe escape
  // sequences.
  return string.replace(rxEscapable, a => {
    const c = meta[a];
    return typeof c === 'string' ? c : `\\u${a.charCodeAt(0).toString(16).padStart(4, '0')}`;
  });
}

let primitiveToJSON;

if (((_global = global) === null || _global === void 0 ? void 0 : (_global$JSON = _global.JSON) === null || _global$JSON === void 0 ? void 0 : _global$JSON.stringify) instanceof Function) {
  try {
    if (JSON.stringify(global.BigInt ? global.BigInt('123') : '') !== '123') throw new Error();
    primitiveToJSON = JSON.stringify;
  } catch (err) {
    // Add support for bigint for primitiveToJSON
    // eslint-disable-next-line no-confusing-arrow
    primitiveToJSON = value => typeof value === 'bigint' ? String(value) : JSON.stringify(value);
  }
} else {
  primitiveToJSON = value => {
    switch (typeof value) {
      case 'string':
        return `"${escapeString(value)}"`;

      case 'number':
        return Number.isFinite(value) ? String(value) : 'null';

      case 'bigint':
        return String(value);

      case 'boolean':
        return value ? 'true' : 'false';

      case 'object':
        if (!value) {
          return 'null';
        }

      // eslint-disable-next-line no-fallthrough

      default:
        // This should never happen, I can't imagine a situation where this executes.
        // If you find a way, please open a ticket or PR
        throw Object.assign(new Error(`Not a primitive "${typeof value}".`), {
          value
        });
    }
  };
}
/*
function quoteString(string: string) {
  return primitiveToJSON(String(string));
}
*/


const cache = new Map();

function quoteString(string) {
  const useCache = string.length < 10000; // eslint-disable-next-line no-lonely-if

  if (useCache && cache.has(string)) {
    return cache.get(string);
  }

  const str = primitiveToJSON(String(string));
  if (useCache) cache.set(string, str);
  return str;
}

function readAsPromised(stream, size) {
  var _stream$_readableStat;

  const value = stream.read(size);

  if (value === null && !(stream.readableEnded || (_stream$_readableStat = stream._readableState) !== null && _stream$_readableStat !== void 0 && _stream$_readableStat.ended)) {
    return new Promise((resolve, reject) => {
      const endListener = () => resolve(null);

      stream.once('end', endListener);
      stream.once('error', reject);
      stream.once('readable', () => {
        stream.removeListener('end', endListener);
        stream.removeListener('error', reject);
        readAsPromised(stream, size).then(resolve, reject);
      });
    });
  }

  return Promise.resolve(value);
}

var ReadState;

(function (ReadState) {
  ReadState[ReadState["Inactive"] = 0] = "Inactive";
  ReadState[ReadState["Reading"] = 1] = "Reading";
  ReadState[ReadState["ReadMore"] = 2] = "ReadMore";
  ReadState[ReadState["Consumed"] = 3] = "Consumed";
})(ReadState || (ReadState = {}));

class JsonStreamStringify extends Readable {
  constructor(input, replacer, spaces, cycle = false, bufferSize = 512) {
    super({
      encoding: 'utf8'
    });

    _defineProperty(this, "cycle", void 0);

    _defineProperty(this, "bufferSize", void 0);

    _defineProperty(this, "item", void 0);

    _defineProperty(this, "indent", void 0);

    _defineProperty(this, "root", void 0);

    _defineProperty(this, "include", void 0);

    _defineProperty(this, "replacer", void 0);

    _defineProperty(this, "visited", void 0);

    _defineProperty(this, "objectItem", void 0);

    _defineProperty(this, "buffer", '');

    _defineProperty(this, "bufferLength", 0);

    _defineProperty(this, "pushCalled", false);

    _defineProperty(this, "readSize", 0);

    _defineProperty(this, "prePush", void 0);

    _defineProperty(this, "readState", ReadState.Inactive);

    this.cycle = cycle;
    this.bufferSize = bufferSize;
    const spaceType = typeof spaces;

    if (spaceType === 'number') {
      this.indent = ' '.repeat(spaces);
    } else if (spaceType === 'string') {
      this.indent = spaces;
    }

    const replacerType = typeof replacer;

    if (replacerType === 'object') {
      this.include = replacer;
    } else if (replacerType === 'function') {
      this.replacer = replacer;
    }

    this.visited = cycle ? new WeakMap() : [];
    this.root = {
      value: {
        '': input
      },
      depth: 0,
      indent: '',
      path: []
    };
    this.setItem(input, this.root, '');
  }

  setItem(value, parent, key = '') {
    // call toJSON where applicable
    if (value && typeof value === 'object' && typeof value.toJSON === 'function') {
      value = value.toJSON(key);
    } // use replacer if applicable


    if (this.replacer) {
      value = this.replacer.call(parent.value, key, value);
    } // coerece functions and symbols into undefined


    if (value instanceof Function || typeof value === 'symbol') {
      value = undefined;
    }

    const type = getType(value);
    let path; // check for circular structure

    if (!this.cycle && type !== Types.Primitive) {
      if (this.visited.some(v => v === value)) {
        this.destroy(Object.assign(new Error('Converting circular structure to JSON'), {
          value,
          key
        }));
        return;
      }

      this.visited.push(value);
    } else if (this.cycle && type !== Types.Primitive) {
      path = this.visited.get(value);

      if (path) {
        this._push(`{"$ref":"$${path.map(v => `[${Number.isInteger(v) ? v : escapeString(quoteString(v))}]`).join('')}"}`);

        this.item = parent;
        return;
      }

      path = parent === this.root ? [] : parent.path.concat(key);
      this.visited.set(value, path);
    }

    if (type === Types.Object) {
      this.setObjectItem(value, parent);
    } else if (type === Types.Array) {
      this.setArrayItem(value, parent);
    } else if (type === Types.Primitive) {
      if (parent !== this.root && typeof key === 'string') {
        // (<any>parent).write(key, primitiveToJSON(value));
        if (value === undefined) ; else {
          this._push(primitiveToJSON(value));
        } // undefined values in objects should be rejected

      } else if (value === undefined && typeof key === 'number') {
        // undefined values in array should be null
        this._push('null');
      } else if (value === undefined) ; else {
        this._push(primitiveToJSON(value));
      }

      this.item = parent;
      return;
    } else if (type === Types.Promise) {
      this.setPromiseItem(value, parent, key);
    } else if (type === Types.ReadableString) {
      this.setReadableStringItem(value, parent);
    } else if (type === Types.ReadableObject) {
      this.setReadableObjectItem(value, parent);
    }

    this.item.value = value;
    this.item.depth = parent.depth + 1;
    if (this.indent) this.item.indent = this.indent.repeat(this.item.depth);
    this.item.path = path;
  }

  setReadableStringItem(input, parent) {
    var _input$_readableState, _input$_readableState2;

    if (input.readableEnded || (_input$_readableState = input._readableState) !== null && _input$_readableState !== void 0 && _input$_readableState.endEmitted) {
      this.emit('error', new Error('Readable Stream has ended before it was serialized. All stream data have been lost'), input, parent.path);
    } else if (input.readableFlowing || (_input$_readableState2 = input._readableState) !== null && _input$_readableState2 !== void 0 && _input$_readableState2.flowing) {
      input.pause();
      this.emit('error', new Error('Readable Stream is in flowing mode, data may have been lost. Trying to pause stream.'), input, parent.path);
    }

    const that = this;
    this.prePush = '"';
    this.item = {
      type: 'readable string',

      async read(size) {
        try {
          const data = await readAsPromised(input, size);

          if (data === null) {
            that._push('"');

            that.item = parent;
            that.unvisit(input);
            return;
          }

          if (data) that._push(escapeString(data.toString()));
        } catch (err) {
          that.emit('error', err);
          that.destroy();
        }
      }

    };
  }

  setReadableObjectItem(input, parent) {
    var _input$_readableState3, _input$_readableState4;

    if (input.readableEnded || (_input$_readableState3 = input._readableState) !== null && _input$_readableState3 !== void 0 && _input$_readableState3.endEmitted) {
      this.emit('error', new Error('Readable Stream has ended before it was serialized. All stream data have been lost'), input, parent.path);
    } else if (input.readableFlowing || (_input$_readableState4 = input._readableState) !== null && _input$_readableState4 !== void 0 && _input$_readableState4.flowing) {
      input.pause();
      this.emit('error', new Error('Readable Stream is in flowing mode, data may have been lost. Trying to pause stream.'), input, parent.path);
    }

    const that = this;

    this._push('[');

    let first = true;
    let i = 0;
    const item = {
      type: 'readable object',

      async read() {
        try {
          let out = '';
          const data = await readAsPromised(input);

          if (data === null) {
            if (i && that.indent) {
              out += `\n${parent.indent}`;
            }

            out += ']';

            that._push(out);

            that.item = parent;
            that.unvisit(input);
            return;
          }

          if (first) first = false;else out += ',';
          if (that.indent) out += `\n${item.indent}`;
          that.prePush = out;
          that.setItem(data, item, i);
          i += 1;
        } catch (err) {
          that.emit('error', err);
          that.destroy();
        }
      }

    };
    this.item = item;
  }

  setPromiseItem(input, parent, key) {
    const that = this;
    let read = false;
    this.item = {
      async read() {
        if (read) return;

        try {
          read = true;
          that.setItem(await input, parent, key);
        } catch (err) {
          that.emit('error', err);
          that.destroy();
        }
      }

    };
  }

  setArrayItem(input, parent) {
    // const entries = input.slice().reverse();
    let i = 0;
    const len = input.length;
    let first = true;
    const that = this;
    const item = {
      read() {
        let out = '';
        let wasFirst = false;

        if (first) {
          first = false;
          wasFirst = true;

          if (!len) {
            that._push('[]');

            that.unvisit(input);
            that.item = parent;
            return;
          }

          out += '[';
        }

        const entry = input[i];

        if (i === len) {
          if (that.indent) out += `\n${parent.indent}`;
          out += ']';

          that._push(out);

          that.item = parent;
          that.unvisit(input);
          return;
        }

        if (!wasFirst) out += ',';
        if (that.indent) out += `\n${item.indent}`;

        that._push(out);

        that.setItem(entry, item, i);
        i += 1;
      }

    };
    this.item = item;
  }

  unvisit(item) {
    if (this.cycle) return;

    const _i = this.visited.indexOf(item);

    if (_i > -1) this.visited.splice(_i, 1);
  }

  setObjectItem(input, parent = undefined) {
    const keys = Object.keys(input);
    let i = 0;
    const len = keys.length;
    let first = true;
    const that = this;
    const {
      include
    } = this;
    let hasItems = false;
    let key;
    const item = {
      read() {
        var _include$indexOf;

        if (i === 0) that._push('{');

        if (i === len) {
          that.objectItem = undefined;

          if (!hasItems) {
            that._push('}');
          } else {
            that._push(`${that.indent ? `\n${parent.indent}` : ''}}`);
          }

          that.item = parent;
          that.unvisit(input);
          return;
        }

        key = keys[i];

        if ((include === null || include === void 0 ? void 0 : (_include$indexOf = include.indexOf) === null || _include$indexOf === void 0 ? void 0 : _include$indexOf.call(include, key)) === -1) {
          // replacer array excludes this key
          i += 1;
          return;
        }

        that.objectItem = item;
        i += 1;
        that.setItem(input[key], item, key);
      },

      write() {
        const out = `${hasItems && !first ? ',' : ''}${item.indent ? `\n${item.indent}` : ''}${quoteString(key)}:${that.indent ? ' ' : ''}`;
        first = false;
        hasItems = true;
        that.objectItem = undefined;
        return out;
      }

    };
    this.item = item;
  }

  _push(data) {
    const out = (this.objectItem ? this.objectItem.write() : '') + data;

    if (this.prePush && out.length) {
      this.buffer += this.prePush;
      this.prePush = undefined;
    }

    this.buffer += out;

    if (this.buffer.length >= this.bufferSize) {
      this.pushCalled = !this.push(this.buffer);
      this.buffer = '';
      this.bufferLength = 0;
      return false;
    }

    return true;
  }

  async _read(size) {
    if (this.readState === ReadState.Consumed) return;

    if (this.readState !== ReadState.Inactive) {
      this.readState = ReadState.ReadMore;
      return;
    }

    this.readState = ReadState.Reading;
    this.pushCalled = false;
    let p;

    while (!this.pushCalled && this.item !== this.root && this.buffer !== undefined) {
      p = this.item.read(size); // eslint-disable-next-line no-await-in-loop

      if (p) await p;
    }

    if (this.buffer === undefined) return;

    if (this.item === this.root) {
      if (this.buffer.length) this.push(this.buffer);
      this.push(null);
      this.readState = ReadState.Consumed;
      this.cleanup();
      return;
    }

    if (this.readState === ReadState.ReadMore) {
      this.readState = ReadState.Inactive;
      await this._read(size);
      return;
    }

    this.readState = ReadState.Inactive;
  }

  cleanup() {
    this.readState = ReadState.Consumed;
    this.buffer = undefined;
    this.visited = undefined;
    this.item = undefined;
    this.root = undefined;
    this.prePush = undefined;
  }

  destroy(error) {
    var _super$destroy;

    if (error) this.emit('error', error);
    (_super$destroy = super.destroy) === null || _super$destroy === void 0 ? void 0 : _super$destroy.call(this);
    this.cleanup();
    return this;
  }

}

export { JsonStreamStringify };
//# sourceMappingURL=index.mjs.map