"use strict"

const _ = require("lodash")
const declarationValueIndex = require("../../utils/declarationValueIndex")
const report = require("../../utils/report")
const ruleMessages = require("../../utils/ruleMessages")
const validateOptions = require("../../utils/validateOptions")
const keywordSets = require("../../reference/keywordSets")
const postcss = require("postcss")
const valueParser = require("postcss-value-parser")

const ruleName = "time-min-milliseconds"

const messages = ruleMessages(ruleName, {
  expected: time => `Expected a minimum of ${time} milliseconds`,
})

const rule = function (minimum) {
  return (root, result) => {
    const validOptions = validateOptions(result, ruleName, {
      actual: minimum,
      possible: _.isNumber,
    })
    if (!validOptions) {
      return
    }

    root.walkDecls(decl => {
      const propertyName = postcss.vendor.unprefixed(decl.prop.toLowerCase())

      if (
        keywordSets.longhandTimeProperties.has(propertyName)
        && !isAcceptableTime(decl.value)
      ) {
        complain(decl)
      }

      if (keywordSets.shorthandTimeProperties.has(propertyName)) {
        const valueList = postcss.list.space(decl.value)

        for (const value of valueList) {
          if (!isAcceptableTime(value)) {
            complain(decl, decl.value.indexOf(value))
          }
        }
      }
    })

    function isAcceptableTime(time) {
      const parsedTime = valueParser.unit(time)

      if (!parsedTime) return true

      if (parsedTime.number <= 0) {
        return true
      }

      if (parsedTime.unit.toLowerCase() === "ms" && parsedTime.number < minimum) {
        return false
      }

      if (parsedTime.unit.toLowerCase() === "s" && parsedTime.number * 1000 < minimum) {
        return false
      }

      return true
    }

    function complain(decl, offset) {
      offset = offset || 0

      report({
        result,
        ruleName,
        message: messages.expected(minimum),
        index: declarationValueIndex(decl) + offset,
        node: decl,
      })
    }
  }
}

rule.ruleName = ruleName
rule.messages = messages
module.exports = rule
