/*
 *  wcwidth.js: a javascript porting of Markus Kuhn's wcwidth()
 */

"use strict"

var defaults = require('defaults')

var combining = require('./combining')


var DEFAULTS = {
    nul:     0,
    control: 0
}


function bisearch(ucs) {
  var min = 0
  var max = combining.length - 1
  var mid

  if (ucs < combining[0][0] || ucs > combining[max][1]) return false

  while (max >= min) {
      mid = Math.floor((min + max) / 2)
      if (ucs > combining[mid][1]) min = mid + 1
      else if (ucs < combining[mid][0]) max = mid - 1
      else return true
  }

  return false
}


function wcwidth(ucs, opts) {
    // test for 8-bit control characters
    if (ucs === 0) return opts.nul
    if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0)) return opts.control

    // binary search in table of non-spacing characters
    if (bisearch(ucs)) return 0

    // if we arrive here, ucs is not a combining or C0/C1 control character
    return 1 +
        (ucs >= 0x1100 &&
         (ucs <= 0x115f ||                       // Hangul Jamo init. consonants
          ucs == 0x2329 || ucs == 0x232a ||
          (ucs >= 0x2e80 && ucs <= 0xa4cf &&
           ucs != 0x303f) ||                     // CJK ... Yi
          (ucs >= 0xac00 && ucs <= 0xd7a3) ||    // Hangul Syllables
          (ucs >= 0xf900 && ucs <= 0xfaff) ||    // CJK Compatibility Ideographs
          (ucs >= 0xfe10 && ucs <= 0xfe19) ||    // Vertical forms
          (ucs >= 0xfe30 && ucs <= 0xfe6f) ||    // CJK Compatibility Forms
          (ucs >= 0xff00 && ucs <= 0xff60) ||    // Fullwidth Forms
          (ucs >= 0xffe0 && ucs <= 0xffe6) ||
          (ucs >= 0x20000 && ucs <= 0x2fffd) ||
          (ucs >= 0x30000 && ucs <= 0x3fffd)));
}


function wcswidth(str, opts) {
    var h, l
    var s = 0, n

    if (typeof str !== 'string') return wcwidth(str, opts)

    for (var i = 0; i < str.length; i++) {
        h = str.charCodeAt(i)
        if (h >= 0xd800 && h <= 0xdbff) {
            l = str.charCodeAt(++i)
            if (l >= 0xdc00 && l <= 0xdfff) h = (h-0xd800)*0x400 + (l-0xdc00)+0x10000
            else i--
        }
        n = wcwidth(h, opts)
        if (n < 0) return -1
        s += n
    }

    return s
}


module.exports = function wcwidth(str) {
  return wcswidth(str, DEFAULTS)
}

module.exports.config = function(opts) {
  opts = Object.assign({}, DEFAULTS, opts || {})
  return function wcwidth(str) {
      return wcswidth(str, opts)
  }
}

// end of wcwidth.js