package timefmt

import (
	"git.swzry.com/zry/YAGTF/yagtf/tfelem"
	"regexp"
	"strconv"
	"strings"
	"time"
)

const parserTokenBufferSize = 128
const regexpTimezoneTag = "^Timezone:([+-][0-9]{4})([A-Z]{3})$"

type TimeElementFactoryFunc func() TimeElement
type NonDisplayTagFunc func(tp *TimePrinter)

type FormatParser struct {
	tagList   map[string]TimeElementFactoryFunc
	ndTagList map[string]NonDisplayTagFunc
	tzsReg    *regexp.Regexp
}

func NewFormatParser() *FormatParser {
	f := &FormatParser{
		tagList:   make(map[string]TimeElementFactoryFunc),
		ndTagList: make(map[string]NonDisplayTagFunc),
	}
	f.addDefaultElementClasses()
	f.tzsReg, _ = regexp.Compile(regexpTimezoneTag)
	return f
}

func (this *FormatParser) AddElementClass(tagname string, ff TimeElementFactoryFunc) {
	this.tagList[tagname] = ff
}

func (this *FormatParser) AddTagAlias(alias string, tagname string) {
	v, ok := this.tagList[tagname]
	if ok {
		this.tagList[alias] = v
	}
}

func (this *FormatParser) AddNonDisplayTag(tagname string, nf NonDisplayTagFunc) {
	this.ndTagList[tagname] = nf
}

func (this *FormatParser) ParseFormatString(tp *TimePrinter, fs string) {
	if len(fs) < 1 {
		return
	}
	if fs[0] == '!' {
		this.parseAdvancedFmt(tp, fs[1:])
	} else {
		this.parseBasicFmt(tp, fs)
	}
}

func (this *FormatParser) parseBasicFmt(tp *TimePrinter, fs string) {
	s := fs
	s = strings.Replace(s, "!", "<#000>", -1)
	s = strings.Replace(s, "yyyy", "<#001>", -1)
	s = strings.Replace(s, "yy", "<#002>", -1)
	s = strings.Replace(s, "MM", "<#003>", -1)
	s = strings.Replace(s, "M3", "<#004>", -1)
	s = strings.Replace(s, "M09", "<#005>", -1)
	s = strings.Replace(s, "M9", "<#006>", -1)
	s = strings.Replace(s, "M", "<#007>", -1)
	s = strings.Replace(s, "dd", "<#008>", -1)
	s = strings.Replace(s, "d", "<#009>", -1)
	s = strings.Replace(s, "HH", "<#010>", -1)
	s = strings.Replace(s, "hh", "<#011>", -1)
	s = strings.Replace(s, "H", "<#012>", -1)
	s = strings.Replace(s, "h", "<#013>", -1)
	s = strings.Replace(s, "mm", "<#014>", -1)
	s = strings.Replace(s, "ss", "<#015>", -1)
	s = strings.Replace(s, "E09", "<#016>", -1)
	s = strings.Replace(s, "E9", "<#017>", -1)
	s = strings.Replace(s, "E3", "<#018>", -1)
	s = strings.Replace(s, "A", "<#019>", -1)
	s = strings.Replace(s, "S1", "<#020>", -1)
	s = strings.Replace(s, "S2", "<#021>", -1)
	s = strings.Replace(s, "S3", "<#022>", -1)
	s = strings.Replace(s, "Z", "<#023>", -1)
	s = strings.Replace(s, "z", "<#024>", -1)
	this.parseAdvancedFmt(tp, s)
}

func (this *FormatParser) parseAdvancedFmt(tp *TimePrinter, fs string) {
	if len(fs) > 1 {
		if fs[0] == '!' {
			this.parseBasicFmt(tp, fs[1:])
			return
		}
	}
	stat := false
	ba := []byte(fs)
	ptbuf := make([]byte, 0, parserTokenBufferSize)
	for _, v := range ba {
		if stat {
			if v == '>' {
				this.processTag(tp, string(ptbuf))
				ptbuf = make([]byte, 0, parserTokenBufferSize)
				stat = false
			} else {
				ptbuf = append(ptbuf, v)
			}
		} else {
			if v == '<' {
				tp.AddPureText(string(ptbuf))
				ptbuf = make([]byte, 0, parserTokenBufferSize)
				stat = true
			} else {
				ptbuf = append(ptbuf, v)
			}
		}
	}
}

func (this *FormatParser) processTimezoneTag(tp *TimePrinter, tzs string, tzname string) {
	sg := 0
	if tzs[0] == '+' {
		sg = 1
	} else if tzs[0] == '-' {
		sg = -1
	} else {
		return
	}
	if len(tzs) != 5 {
		return
	}
	hs := tzs[1:3]
	ms := tzs[3:5]
	hi, err := strconv.Atoi(hs)
	if err != nil {
		return
	}
	mi, err := strconv.Atoi(ms)
	if err != nil {
		return
	}
	ofs := (hi*3600 + mi*60) * sg
	tz := time.FixedZone(tzname, ofs)
	tp.UseTimezone(tz)
}

func (this *FormatParser) processTag(tp *TimePrinter, tag string) {
	rrs := this.tzsReg.FindStringSubmatch(tag)
	if len(rrs) == 3 {
		this.processTimezoneTag(tp, rrs[1], rrs[2])
		return
	}
	v1, ok := this.ndTagList[tag]
	if ok {
		v1(tp)
		return
	}
	v2, ok := this.tagList[tag]
	if ok {
		tp.AddElement(v2())
	} else {
		tp.AddPureText("<" + tag + ">")
	}
}

func (this *FormatParser) addDefaultElementClasses() {
	this.AddNonDisplayTag("UTC", func(tp *TimePrinter) { tp.UseUTC() })
	this.AddNonDisplayTag("Local", func(tp *TimePrinter) { tp.UseLocalTimezone() })
	this.AddElementClass("year", func() TimeElement { return tfelem.NewYearElement(false) })
	this.AddElementClass("shortYear", func() TimeElement { return tfelem.NewYearElement(true) })
	this.AddElementClass("month", func() TimeElement { return tfelem.NewNumbericMonthElement(true) })
	this.AddElementClass("monthNoFill", func() TimeElement { return tfelem.NewNumbericMonthElement(false) })
	this.AddElementClass("monthAbbr", func() TimeElement { return tfelem.NewEnglishMonthElement(true, false) })
	this.AddElementClass("monthName", func() TimeElement { return tfelem.NewEnglishMonthElement(false, true) })
	this.AddElementClass("monthNameNoFill", func() TimeElement { return tfelem.NewEnglishMonthElement(false, false) })
	this.AddElementClass("day", func() TimeElement { return tfelem.NewDayElement(true) })
	this.AddElementClass("dayNoFill", func() TimeElement { return tfelem.NewDayElement(false) })
	this.AddElementClass("hour24", func() TimeElement { return tfelem.NewHour24hElement(true) })
	this.AddElementClass("hour24NoFill", func() TimeElement { return tfelem.NewHour24hElement(false) })
	this.AddElementClass("hour12", func() TimeElement { return tfelem.NewHour12hElement(true) })
	this.AddElementClass("hour12NoFill", func() TimeElement { return tfelem.NewHour12hElement(false) })
	this.AddElementClass("minute", func() TimeElement { return tfelem.NewMinuteElement() })
	this.AddElementClass("second", func() TimeElement { return tfelem.NewSecondElement() })
	this.AddElementClass("ms", func() TimeElement { return tfelem.NewSecondFloatPartElementWithMilliSec() })
	this.AddElementClass("us", func() TimeElement { return tfelem.NewSecondFloatPartElementWithMicroSec() })
	this.AddElementClass("ns", func() TimeElement { return tfelem.NewSecondFloatPartElementWithNanoSec() })
	this.AddElementClass("weekday", func() TimeElement { return tfelem.NewNumbericWeekDayElement() })
	this.AddElementClass("weekdayAbbr", func() TimeElement { return tfelem.NewEnglishWeekDayElement(true, false) })
	this.AddElementClass("weekdayName", func() TimeElement { return tfelem.NewEnglishWeekDayElement(false, true) })
	this.AddElementClass("weekdayNameNoFill", func() TimeElement { return tfelem.NewEnglishWeekDayElement(false, false) })
	this.AddElementClass("ampm", func() TimeElement { return tfelem.NewAMPMElement() })
	this.AddElementClass("yearweek", func() TimeElement { return tfelem.NewWeekElement(true) })
	this.AddElementClass("yearweekNoFill", func() TimeElement { return tfelem.NewWeekElement(false) })
	this.AddElementClass("yearday", func() TimeElement { return tfelem.NewYearDayElement(true) })
	this.AddElementClass("yeardayNoFill", func() TimeElement { return tfelem.NewYearDayElement(false) })
	this.AddElementClass("timezone", func() TimeElement { return tfelem.NewTimeZoneUTCOffsetElement() })
	this.AddElementClass("timezoneAbbr", func() TimeElement { return tfelem.NewTimeZoneAbbrElement() })
	this.AddElementClass("timezoneSec", func() TimeElement { return tfelem.NewTimeZoneNumbericOffsetElement(true) })
	this.AddElementClass("timezoneSecNoFill", func() TimeElement { return tfelem.NewTimeZoneNumbericOffsetElement(false) })
	this.AddElementClass("iso8601date", func() TimeElement { return tfelem.NewISO8601DateElement() })
	this.AddElementClass("iso8601time", func() TimeElement { return tfelem.NewISO8601TimeElement() })
	this.AddElementClass("iso8601full", func() TimeElement { return tfelem.NewISO8601FullElement() })
	this.AddElementClass("common", func() TimeElement { return tfelem.NewCommonDatetimeElement() })
	this.AddElementClass("nginx", func() TimeElement { return tfelem.NewNginxDefaultElement() })
	this.AddElementClass("!", func() TimeElement { return &tfelem.PureTextElement{PureText: "!"} })
	this.AddElementClass("lt", func() TimeElement { return &tfelem.PureTextElement{PureText: "<"} })
	this.AddElementClass("gt", func() TimeElement { return &tfelem.PureTextElement{PureText: ">"} })
	this.AddElementClass("q", func() TimeElement { return &tfelem.PureTextElement{PureText: `"`} })
	this.AddElementClass("sq", func() TimeElement { return &tfelem.PureTextElement{PureText: "'"} })
	this.AddElementClass("tab", func() TimeElement { return &tfelem.PureTextElement{PureText: "\t"} })
	this.AddElementClass("br", func() TimeElement { return &tfelem.PureTextElement{PureText: "\n"} })
	this.AddElementClass("cr", func() TimeElement { return &tfelem.PureTextElement{PureText: "\r"} })
	this.AddElementClass("sp", func() TimeElement { return &tfelem.PureTextElement{PureText: "!"} })
	this.AddTagAlias("y", "year")
	this.AddTagAlias("sy", "shortYear")
	this.AddTagAlias("mon", "month")
	this.AddTagAlias("monNF", "monthNoFill")
	this.AddTagAlias("monA", "monthAbbr")
	this.AddTagAlias("monN", "monthName")
	this.AddTagAlias("monNNF", "monthNameNoFill")
	this.AddTagAlias("d", "day")
	this.AddTagAlias("dNF", "dayNoFill")
	this.AddTagAlias("h24", "hour24")
	this.AddTagAlias("h12", "hour12")
	this.AddTagAlias("h24NF", "hour24NoFill")
	this.AddTagAlias("h12NF", "hour12NoFill")
	this.AddTagAlias("min", "minute")
	this.AddTagAlias("s", "second")
	this.AddTagAlias("wd", "weekday")
	this.AddTagAlias("wdN", "weekdayName")
	this.AddTagAlias("wdNNF", "weekdayNameNoFill")
	this.AddTagAlias("wdA", "weekdayAbbr")
	this.AddTagAlias("yw", "yearweek")
	this.AddTagAlias("ywNF", "yearweekNoFill")
	this.AddTagAlias("yd", "yearday")
	this.AddTagAlias("ydNF", "yeardayNoFill")
	this.AddTagAlias("tz", "timezone")
	this.AddTagAlias("tzA", "timezoneAbbr")
	this.AddTagAlias("tzS", "timezoneSec")
	this.AddTagAlias("tzSNF", "timezoneSecNoFill")
	this.AddTagAlias("i8d", "iso8601date")
	this.AddTagAlias("i8t", "iso8601time")
	this.AddTagAlias("i8f", "iso8601full")
	this.AddTagAlias("#000", "!")
	this.AddTagAlias("#001", "year")
	this.AddTagAlias("#002", "shortYear")
	this.AddTagAlias("#003", "month")
	this.AddTagAlias("#004", "monthAbbr")
	this.AddTagAlias("#005", "monthName")
	this.AddTagAlias("#006", "monthNameNoFill")
	this.AddTagAlias("#007", "monthNoFill")
	this.AddTagAlias("#008", "day")
	this.AddTagAlias("#009", "dayNoFill")
	this.AddTagAlias("#010", "hour24")
	this.AddTagAlias("#011", "hour12")
	this.AddTagAlias("#012", "hour24NoFill")
	this.AddTagAlias("#013", "hour12NoFill")
	this.AddTagAlias("#014", "minute")
	this.AddTagAlias("#015", "second")
	this.AddTagAlias("#016", "weekdayName")
	this.AddTagAlias("#017", "weekdayNameNoFill")
	this.AddTagAlias("#018", "weekdayAbbr")
	this.AddTagAlias("#019", "ampm")
	this.AddTagAlias("#020", "ms")
	this.AddTagAlias("#021", "us")
	this.AddTagAlias("#022", "ns")
	this.AddTagAlias("#023", "timezoneAbbr")
	this.AddTagAlias("#024", "timezone")
}