import { Anot, escapeRegExp, isObject } from '../seed/core'
import { $$skipArray } from '../vmodel/reserved'

export function orderBy(array, by, decend) {
  var type = Anot.type(array)
  if (type !== 'array' && type !== 'object') throw 'orderBy只能处理对象或数组'
  var criteria =
    typeof by == 'string'
      ? function(el) {
          return el && el[by]
        }
      : typeof by === 'function'
      ? by
      : function(el) {
          return el
        }
  var mapping = {}
  var temp = []
  __repeat(array, Array.isArray(array), function(key) {
    var val = array[key]
    var k = criteria(val, key)
    if (k in mapping) {
      mapping[k].push(key)
    } else {
      mapping[k] = [key]
    }
    temp.push(k)
  })

  temp.sort()
  if (decend < 0) {
    temp.reverse()
  }
  var _array = type === 'array'
  var target = _array ? [] : {}
  return recovery(target, temp, function(k) {
    var key = mapping[k].shift()
    if (_array) {
      target.push(array[key])
    } else {
      target[key] = array[key]
    }
  })
}

function __repeat(array, isArray, cb) {
  if (isArray) {
    array.forEach(function(val, index) {
      cb(index)
    })
  } else if (typeof array.$track === 'string') {
    array.$track.replace(/[^☥]+/g, function(k) {
      cb(k)
    })
  } else {
    for (var i in array) {
      if (array.hasOwnProperty(i)) {
        cb(i)
      }
    }
  }
}
export function filterBy(array, search, ...args) {
  var type = Anot.type(array)
  if (type !== 'array' && type !== 'object') {
    throw 'filterBy只能处理对象或数组'
  }
  var stype = Anot.type(search)
  if (stype === 'function') {
    var criteria = search._orig || search
  } else if (stype === 'string' || stype === 'number') {
    if (search === '') {
      return array
    } else {
      var reg = new RegExp(escapeRegExp(search), 'i')
      criteria = function(el) {
        return reg.test(el)
      }
    }
  } else {
    return array
  }
  var isArray = type === 'array'
  var target = isArray ? [] : {}
  __repeat(array, isArray, function(key) {
    var val = array[key]
    if (criteria.apply({ key }, [val, key].concat(args))) {
      if (isArray) {
        target.push(val)
      } else {
        target[key] = val
      }
    }
  })
  return target
}

export function selectBy(data, array, defaults) {
  if (isObject(data) && !Array.isArray(data)) {
    var target = []
    return recovery(target, array, function(name) {
      target.push(
        data.hasOwnProperty(name) ? data[name] : defaults ? defaults[name] : ''
      )
    })
  } else {
    return data
  }
}

export function limitBy(input, limit, begin) {
  var type = Anot.type(input)
  if (type !== 'array' && type !== 'object') {
    throw 'limitBy只能处理对象或数组'
  }
  //必须是数值
  if (typeof limit !== 'number') {
    return input
  }
  //不能为NaN
  if (limit !== limit) {
    return input
  }
  //将目标转换为数组
  if (type === 'object') {
    input = convertArray(input, false)
  }
  var n = input.length
  limit = Math.floor(Math.min(n, limit))
  begin = typeof begin === 'number' ? begin : 0
  if (begin < 0) {
    begin = Math.max(0, n + begin)
  }
  var data = []
  for (var i = begin; i < n; i++) {
    if (data.length === limit) {
      break
    }
    data.push(input[i])
  }
  var isArray = type === 'array'
  if (isArray) {
    return data
  }
  var target = {}
  return recovery(target, data, function(el) {
    target[el.key] = el.value
  })
}

function recovery(ret, array, callback) {
  for (var i = 0, n = array.length; i < n; i++) {
    callback(array[i])
  }
  return ret
}

//Chrome谷歌浏览器中js代码Array.sort排序的bug乱序解决办法
//http://www.cnblogs.com/yzeng/p/3949182.html
function convertArray(array, isArray) {
  var ret = [],
    i = 0
  __repeat(array, isArray, function(key) {
    ret[i] = {
      oldIndex: i,
      value: array[key],
      key: key
    }
    i++
  })
  return ret
}