import { default as Yasqe, Token, Position } from "./";

/**
 * When typing a query, this query is sometimes syntactically invalid, causing
 * the current tokens to be incorrect This causes problem for autocompletion.
 * http://bla might result in two tokens: http:// and bla. We'll want to combine
 * these
 */

export function getCompleteToken(yasqe: Yasqe, token?: Token, cur?: Position): Token {
  if (!cur) {
    cur = yasqe.getDoc().getCursor() as Position;
  }
  if (!token) {
    token = yasqe.getTokenAt(cur) as Token;
  }

  return expandTokenToEnd(yasqe, expandTokenToStart(yasqe, token, cur), cur);
}
function expandTokenToStart(yasqe: Yasqe, token: Token, cur: Position): Token {
  var prevToken: Token = yasqe.getTokenAt({
    line: cur.line,
    ch: token.start,
  });

  if ((token.type === "punc" || token.type === "error") && !token.state.possibleFullIri && !token.state.inPrefixDecl) {
    token.state.possibleCurrent = token.state.possibleNext;
    return token;
  }
  if (prevToken.type === "punc" && !prevToken.state.possibleFullIri && !prevToken.state.inPrefixDecl) {
    //assuming this is a path expression. Should not expand the token anymore
    //Also checking whether current token isnt an error, to avoid stopping on iri path delimiters
    return token;
  }
  // not start of line, and not whitespace
  if (prevToken.type != null && prevToken.type != "ws" && token.type != null && token.type != "ws") {
    token.start = prevToken.start;
    token.string = prevToken.string + token.string;
    return expandTokenToStart(yasqe, token, {
      line: cur.line,
      ch: prevToken.start,
    }); // recursively, might have multiple tokens which it should include
  } else if (token.type != null && token.type == "ws") {
    //always keep 1 char of whitespace between tokens. Otherwise, autocompletions might end up next to the previous node, without whitespace between them
    token.start = token.start + 1;
    token.string = token.string.substring(1);
    return token;
  } else {
    return token;
  }
}

function expandTokenToEnd(yasqe: Yasqe, token: Token, cur: Position): Token {
  if (token.string.indexOf(" ") >= 0) {
    /**
     * This is most likely a query ending with `<http://www.opengis.net/ont/geosparql# ?a`
     *                                                                                ^ cursor
     * In this case, separate by whitespace, and assume we're finished
     */
    const whitespaceIndex = token.string.indexOf(" ");
    token.string = token.string.substr(0, whitespaceIndex);
    token.end = token.start + token.string.length;
    return token;
  }
  if (!token.type) return token;

  var nextToken: Token = yasqe.getTokenAt({
    line: cur.line,
    ch: token.end + 1,
  });

  if (
    // not end of line
    nextToken.type !== "ws" &&
    //not a punctuation (for eg '?subject}', we dont want to include '}')
    token.state.possibleFullIri &&
    //not whitespace
    token.type !== null &&
    token.type !== "ws" &&
    // Avoid infinite loops as CM will give back the last token of in a line when requesting something larger then the lines length
    nextToken.end !== token.end
  ) {
    token.end = nextToken.end;
    token.string = token.string + nextToken.string;
    return expandTokenToEnd(yasqe, token, {
      line: cur.line,
      ch: nextToken.end,
    }); // recursively, might have multiple tokens which it should include
  } else if (token.type === "ws") {
    //always keep 1 char of whitespace between tokens. Otherwise, autocompletions might end up next to the previous node, without whitespace between them
    token.end = token.end + 1;
    token.string = token.string.substring(token.string.length - 1);
    return token;
  } else {
    return token;
  }
}
export function getPreviousNonWsToken(yasqe: Yasqe, line: number, token: Token): Token {
  var previousToken = yasqe.getTokenAt({
    line: line,
    ch: token.start,
  });
  if (previousToken != null && previousToken.type == "ws") {
    previousToken = getPreviousNonWsToken(yasqe, line, previousToken);
  }
  return previousToken;
}
export function getNextNonWsToken(yasqe: Yasqe, lineNumber: number, charNumber?: number): Token | undefined {
  if (charNumber == undefined) charNumber = 1;
  var token = yasqe.getTokenAt({
    line: lineNumber,
    ch: charNumber,
  });
  if (token == null || token == undefined || token.end < charNumber) {
    return undefined;
  }
  if (token.type == "ws") {
    return getNextNonWsToken(yasqe, lineNumber, token.end + 1);
  }
  return token;
}