/*
* Copyright 2004-2023 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (https://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.bnf;
import java.util.HashMap;
/**
* Represents a hard coded terminal rule in a BNF object.
*/
public class RuleFixed implements Rule {
public static final int YMD = 0;
public static final int HMS = YMD + 1;
public static final int NANOS = HMS + 1;
public static final int ANY_EXCEPT_SINGLE_QUOTE = NANOS + 1;
public static final int ANY_EXCEPT_DOUBLE_QUOTE = ANY_EXCEPT_SINGLE_QUOTE + 1;
public static final int ANY_UNTIL_EOL = ANY_EXCEPT_DOUBLE_QUOTE + 1;
public static final int ANY_UNTIL_END = ANY_UNTIL_EOL + 1;
public static final int ANY_WORD = ANY_UNTIL_END + 1;
public static final int ANY_EXCEPT_2_DOLLAR = ANY_WORD + 1;
public static final int HEX_START = ANY_EXCEPT_2_DOLLAR + 1;
public static final int OCTAL_START = HEX_START + 1;
public static final int BINARY_START = OCTAL_START + 1;
public static final int CONCAT = BINARY_START + 1;
public static final int AZ_UNDERSCORE = CONCAT + 1;
public static final int AF = AZ_UNDERSCORE + 1;
public static final int DIGIT = AF + 1;
public static final int OPEN_BRACKET = DIGIT + 1;
public static final int CLOSE_BRACKET = OPEN_BRACKET + 1;
public static final int JSON_TEXT = CLOSE_BRACKET + 1;
private final int type;
RuleFixed(int type) {
this.type = type;
}
@Override
public void accept(BnfVisitor visitor) {
visitor.visitRuleFixed(type);
}
@Override
public void setLinks(HashMap<String, RuleHead> ruleMap) {
// nothing to do
}
@Override
public boolean autoComplete(Sentence sentence) {
sentence.stopIfRequired();
String query = sentence.getQuery();
String s = query;
boolean removeTrailingSpaces = false;
switch (type) {
case YMD:
while (s.length() > 0 && "0123456789-".indexOf(s.charAt(0)) >= 0) {
s = s.substring(1);
}
if (s.length() == 0) {
sentence.add("2006-01-01", "1", Sentence.KEYWORD);
}
// needed for timestamps
removeTrailingSpaces = true;
break;
case HMS:
while (s.length() > 0 && "0123456789:".indexOf(s.charAt(0)) >= 0) {
s = s.substring(1);
}
if (s.length() == 0) {
sentence.add("12:00:00", "1", Sentence.KEYWORD);
}
break;
case NANOS:
while (s.length() > 0 && Character.isDigit(s.charAt(0))) {
s = s.substring(1);
}
if (s.length() == 0) {
sentence.add("nanoseconds", "0", Sentence.KEYWORD);
}
removeTrailingSpaces = true;
break;
case ANY_EXCEPT_SINGLE_QUOTE:
while (true) {
while (s.length() > 0 && s.charAt(0) != '\'') {
s = s.substring(1);
}
if (s.startsWith("''")) {
s = s.substring(2);
} else {
break;
}
}
if (s.length() == 0) {
sentence.add("anything", "Hello World", Sentence.KEYWORD);
sentence.add("'", "'", Sentence.KEYWORD);
}
break;
case ANY_EXCEPT_2_DOLLAR:
while (s.length() > 0 && !s.startsWith("$$")) {
s = s.substring(1);
}
if (s.length() == 0) {
sentence.add("anything", "Hello World", Sentence.KEYWORD);
sentence.add("$$", "$$", Sentence.KEYWORD);
}
break;
case ANY_EXCEPT_DOUBLE_QUOTE:
while (true) {
while (s.length() > 0 && s.charAt(0) != '\"') {
s = s.substring(1);
}
if (s.startsWith("\"\"")) {
s = s.substring(2);
} else {
break;
}
}
if (s.length() == 0) {
sentence.add("anything", "identifier", Sentence.KEYWORD);
sentence.add("\"", "\"", Sentence.KEYWORD);
}
break;
case ANY_WORD:
case JSON_TEXT:
while (s.length() > 0 && !Bnf.startWithSpace(s)) {
s = s.substring(1);
}
if (s.length() == 0) {
sentence.add("anything", "anything", Sentence.KEYWORD);
}
break;
case HEX_START:
if (s.startsWith("0X") || s.startsWith("0x")) {
s = s.substring(2);
} else if ("0".equals(s)) {
sentence.add("0x", "x", Sentence.KEYWORD);
} else if (s.length() == 0) {
sentence.add("0x", "0x", Sentence.KEYWORD);
}
break;
case OCTAL_START:
if (s.startsWith("0O") || s.startsWith("0o")) {
s = s.substring(2);
} else if ("0".equals(s)) {
sentence.add("0o", "o", Sentence.KEYWORD);
} else if (s.length() == 0) {
sentence.add("0o", "0o", Sentence.KEYWORD);
}
break;
case BINARY_START:
if (s.startsWith("0B") || s.startsWith("0b")) {
s = s.substring(2);
} else if ("0".equals(s)) {
sentence.add("0b", "b", Sentence.KEYWORD);
} else if (s.length() == 0) {
sentence.add("0b", "0b", Sentence.KEYWORD);
}
break;
case CONCAT:
if (s.equals("|")) {
sentence.add("||", "|", Sentence.KEYWORD);
} else if (s.startsWith("||")) {
s = s.substring(2);
} else if (s.length() == 0) {
sentence.add("||", "||", Sentence.KEYWORD);
}
removeTrailingSpaces = true;
break;
case AZ_UNDERSCORE:
if (s.length() > 0 &&
(Character.isLetter(s.charAt(0)) || s.charAt(0) == '_')) {
s = s.substring(1);
}
if (s.length() == 0) {
sentence.add("character", "A", Sentence.KEYWORD);
}
break;
case AF:
if (s.length() > 0) {
char ch = Character.toUpperCase(s.charAt(0));
if (ch >= 'A' && ch <= 'F') {
s = s.substring(1);
}
}
if (s.length() == 0) {
sentence.add("hex character", "0A", Sentence.KEYWORD);
}
break;
case DIGIT:
if (s.length() > 0 && Character.isDigit(s.charAt(0))) {
s = s.substring(1);
}
if (s.length() == 0) {
sentence.add("digit", "1", Sentence.KEYWORD);
}
break;
case OPEN_BRACKET:
if (s.length() == 0) {
sentence.add("[", "[", Sentence.KEYWORD);
} else if (s.charAt(0) == '[') {
s = s.substring(1);
}
removeTrailingSpaces = true;
break;
case CLOSE_BRACKET:
if (s.length() == 0) {
sentence.add("]", "]", Sentence.KEYWORD);
} else if (s.charAt(0) == ']') {
s = s.substring(1);
}
removeTrailingSpaces = true;
break;
// no autocomplete support for comments
// (comments are not reachable in the bnf tree)
case ANY_UNTIL_EOL:
case ANY_UNTIL_END:
default:
throw new AssertionError("type="+type);
}
if (!s.equals(query)) {
// can not always remove spaces here, because a repeat
// rule for a-z would remove multiple words
// but we have to remove spaces after '||'
// and after ']'
if (removeTrailingSpaces) {
while (Bnf.startWithSpace(s)) {
s = s.substring(1);
}
}
sentence.setQuery(s);
return true;
}
return false;
}
@Override
public String toString() {
return "#" + type;
}
}