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'use strict';
// based on code from Brian White @mscdex mariasql library - https://github.com/mscdex/node-mariasql/blob/master/lib/Client.js#L272-L332
// License: https://github.com/mscdex/node-mariasql/blob/master/LICENSE
const RE_PARAM = /(?:\?)|(?::(\d+|(?:[a-zA-Z][a-zA-Z0-9_]*)))/g,
DQUOTE = 34,
SQUOTE = 39,
BSLASH = 92;
function parse(query) {
let ppos = RE_PARAM.exec(query);
let curpos = 0;
let start = 0;
let end;
const parts = [];
let inQuote = false;
let escape = false;
let qchr;
const tokens = [];
let qcnt = 0;
let lastTokenEndPos = 0;
let i;
if (ppos) {
do {
for (i=curpos,end=ppos.index; i<end; ++i) {
let chr = query.charCodeAt(i);
if (chr === BSLASH)
escape = !escape;
else {
if (escape) {
escape = false;
continue;
}
if (inQuote && chr === qchr) {
if (query.charCodeAt(i + 1) === qchr) {
// quote escaped via "" or ''
++i;
continue;
}
inQuote = false;
} else if (chr === DQUOTE || chr === SQUOTE) {
inQuote = true;
qchr = chr;
}
}
}
if (!inQuote) {
parts.push(query.substring(start, end));
tokens.push(ppos[0].length === 1 ? qcnt++ : ppos[1]);
start = end + ppos[0].length;
lastTokenEndPos = start;
}
curpos = end + ppos[0].length;
} while (ppos = RE_PARAM.exec(query));
if (tokens.length) {
if (curpos < query.length) {
parts.push(query.substring(lastTokenEndPos));
}
return [parts, tokens];
}
}
return [query];
};
function createCompiler(config) {
if (!config)
config = {};
if (!config.placeholder) {
config.placeholder = '?';
}
let ncache = 100;
let cache;
if (typeof config.cache === 'number') {
ncache = config.cache;
}
if (typeof config.cache === 'object') {
cache = config.cache;
}
if (config.cache !== false && !cache) {
cache = new (require('lru-cache'))({ max: ncache });
}
function toArrayParams(tree, params) {
const arr = [];
if (tree.length == 1) {
return [tree[0], []];
}
if (typeof params == 'undefined')
throw new Error('Named query contains placeholders, but parameters object is undefined');
const tokens = tree[1];
for (let i=0; i < tokens.length; ++i) {
arr.push(params[tokens[i]]);
}
return [tree[0], arr];
}
function noTailingSemicolon(s) {
if (s.slice(-1) == ':') {
return s.slice(0, -1);
}
return s;
}
function join(tree) {
if (tree.length == 1) {
return tree;
}
let unnamed = noTailingSemicolon(tree[0][0]);
for (let i=1; i < tree[0].length; ++i) {
if (tree[0][i-1].slice(-1) == ':') {
unnamed += config.placeholder;
}
unnamed += config.placeholder;
unnamed += noTailingSemicolon(tree[0][i]);
}
const last = tree[0][tree[0].length -1];
if (tree[0].length == tree[1].length) {
if (last.slice(-1) == ':') {
unnamed += config.placeholder;
}
unnamed += config.placeholder;
}
return [unnamed, tree[1]];
}
function compile(query, paramsObj) {
let tree;
if (cache && (tree = cache.get(query))) {
return toArrayParams(tree, paramsObj)
}
tree = join(parse(query));
if(cache) {
cache.set(query, tree);
}
return toArrayParams(tree, paramsObj);
}
compile.parse = parse;
return compile;
}
// named :one :two to postgres-style numbered $1 $2 $3
function toNumbered(q, params) {
const tree = parse(q);
const paramsArr = [];
if (tree.length == 1) {
return [tree[0], paramsArr];
}
const pIndexes = {};
let pLastIndex = 0;
let qs = '';
let varIndex;
const varNames = [];
for (let i=0; i < tree[0].length; ++i) {
varIndex = pIndexes[tree[1][i]];
if (!varIndex) {
varIndex = ++pLastIndex;
pIndexes[tree[1][i]] = varIndex;
}
if (tree[1][i]) {
varNames[varIndex - 1] = tree[1][i];
qs += tree[0][i] + '$' + varIndex;
} else {
qs += tree[0][i];
}
}
return [qs, varNames.map(n => params[n])];
}
module.exports = createCompiler;
module.exports.toNumbered = toNumbered;
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