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// Based of https://github.com/bendrucker/postgres-array// Copyright (c) Ben Drucker <bvdrucker@gmail.com> (bendrucker.me). MIT License.
type AllowedSeparators = "," | ";";/** Incorrectly parsed data types default to null */type ArrayResult<T> = Array<T | null | ArrayResult<T>>;type Transformer<T> = (value: string) => T;
export function parseArray<T>(  source: string,  transform: Transformer<T>,  separator: AllowedSeparators = ",",) {  return new ArrayParser(source, transform, separator).parse();}
class ArrayParser<T> {  position = 0;  entries: ArrayResult<T> = [];  recorded: string[] = [];  dimension = 0;
  constructor(    public source: string,    public transform: Transformer<T>,    public separator: AllowedSeparators,  ) {}
  isEof(): boolean {    return this.position >= this.source.length;  }
  nextCharacter() {    const character = this.source[this.position++];    if (character === "\\") {      return {        value: this.source[this.position++],        escaped: true,      };    }    return {      value: character,      escaped: false,    };  }
  record(character: string): void {    this.recorded.push(character);  }
  newEntry(includeEmpty = false): void {    let entry;    if (this.recorded.length > 0 || includeEmpty) {      entry = this.recorded.join("");      if (entry === "NULL" && !includeEmpty) {        entry = null;      }      if (entry !== null) entry = this.transform(entry);      this.entries.push(entry);      this.recorded = [];    }  }
  consumeDimensions(): void {    if (this.source[0] === "[") {      while (!this.isEof()) {        const char = this.nextCharacter();        if (char.value === "=") break;      }    }  }
  parse(nested = false): ArrayResult<T> {    let character, parser, quote;    this.consumeDimensions();    while (!this.isEof()) {      character = this.nextCharacter();      if (character.value === "{" && !quote) {        this.dimension++;        if (this.dimension > 1) {          parser = new ArrayParser(            this.source.substr(this.position - 1),            this.transform,            this.separator,          );          this.entries.push(parser.parse(true));          this.position += parser.position - 2;        }      } else if (character.value === "}" && !quote) {        this.dimension--;        if (!this.dimension) {          this.newEntry();          if (nested) return this.entries;        }      } else if (character.value === '"' && !character.escaped) {        if (quote) this.newEntry(true);        quote = !quote;      } else if (character.value === this.separator && !quote) {        this.newEntry();      } else {        this.record(character.value);      }    }    if (this.dimension !== 0) {      throw new Error("array dimension not balanced");    }    return this.entries;  }}