'use strict';

let postcss = require('postcss');

let pxRegExp = /\b(\d+(\.\d+)?)px\b/;
let pxGlobalRegExp = new RegExp(pxRegExp.source, 'g');

module.exports = postcss.plugin('postcss-px2rem', (option) => {
  let opt = Object.assign({
    scale: 0.5,
    ignore: []
  }, option)

  return (root, result) => {
    const file = root.source.input.file
    const ignore = opt.ignore || []
    for (const ignoreElement of ignore) {
      const regExp = new RegExp(ignoreElement)
      if (regExp.test(file)) return
    }
    root.walkDecls(function (decl) {
      if (/px/.test(decl.value)) {
        decl.value = decl.value.replace(pxGlobalRegExp, function (match, p1) {
          return p1 * opt.scale + 'px'
        })
      }
    })
    result.root = root
  };
});