package cli

import (
	"regexp"
	"strconv"

	"gitea.zaclys.com/bvaudour/gob/option"
	"gitea.zaclys.net/bvaudour/go-calc/calc"
)

var (
	otherFunctions = map[string]func() option.Option[error]{
		"h": printHelp,
		"q": quit,
	}

	calcFunctions = map[string]calc.CalcFunc{
		"op":  printOption,
		"of":  fixPrecision(true),
		"oa":  fixPrecision(false),
		"p":   printLast,
		"P":   printStack,
		"c":   calc.Pop,
		"C":   calc.Reset,
		"d":   calc.Duplicate,
		"D":   calc.DuplicateStack,
		"r":   calc.Reverse,
		"R":   calc.ReverseStack,
		"s":   calc.Sort,
		"S":   calc.SortDesc,
		":P":  printRegistries,
		":C":  calc.ResetRegistries,
		";C":  calc.ResetMacros,
		"|":   calc.Abs,
		"++":  calc.Inc,
		"--":  calc.Dec,
		"inv": calc.Inv,
		"+":   calc.Add,
		"-":   calc.Sub,
		"−":   calc.Sub,
		"*":   calc.Mul,
		"×":   calc.Mul,
		"/":   calc.Div,
		"÷":   calc.Div,
		"//":  calc.Quo,
		"%":   calc.Rem,
		"²":   calc.Square,
		"^":   calc.Pow,
		"v":   calc.Sqrt,
		"√":   calc.Sqrt,
		"vn":  calc.Sqrtn,
		"!":   calc.Fact,
		"<=>": calc.Cmp,
		"=":   calc.Eq,
		"<>":  calc.Ne,
		"≠":   calc.Ne,
		">":   calc.Gt,
		">=":  calc.Ge,
		"≥":   calc.Ge,
		"<=":  calc.Le,
		"≤":   calc.Le,
		"cb":  calc.ToBase(2),
		"co":  calc.ToBase(8),
		"cx":  calc.ToBase(16),
		"ci":  calc.ToInteger[uint](),
		"cd":  calc.ToDecimal[uint](),
		"cs":  calc.ToScientific[uint](),
		"cf":  calc.ToFraction[uint](),
		">>":  calc.Rsh,
		"<<":  calc.Lsh,
		"min": calc.Min,
		"max": calc.Max,
		"sum": calc.Sum,
		"moy": calc.Mean,
		"med": calc.Median,
		"mod": calc.Mode,
		"var": calc.Variance,
		"dev": calc.StdDeviation,
		"l": func(c *calc.Calc) (err option.Option[error]) {
			c.Len()
			return
		},
		"n": calc.NoAction,
	}

	wordCalcFunctions = map[string]calc.WordCalcFunc{
		`^:p\w+$`: printRegistry,
		`^:c\w+$`: calc.ResetRegistry,
		`^:l\w+$`: calc.Load,
		`^:s\w+$`: calc.Store,
		`^:S\w+$`: calc.StoreStack,
		`^;x\w+$`: execMacro,
	}

	intCalcFunctions = map[string]calc.IntCalcFunc[uint64]{
		`^c\d+$`: func(base ...uint64) calc.CalcFunc {
			if len(base) > 0 {
				return calc.ToBase(base[0])
			}
			return func(c *calc.Calc) (err option.Option[error]) { return }
		},
		`^ci\d+$`: calc.ToInteger[uint64],
		`^cd\d+$`: calc.ToDecimal[uint64],
		`^cs\d+$`: calc.ToScientific[uint64],
		`^cf\d+$`: calc.ToFraction[uint64],
		`^of\d+$`: precision[uint64](true),
		`^oa\d+$`: precision[uint64](false),
	}

	cliFunctions = map[string]CliFunc{
		";P": printMacros,
		"[":  startMacro,
		"?":  startAlt,
	}

	wordCliFunctions = map[string]WordCliFunc{
		`^;p\w+$`: printMacro,
		`^;c\w+$`: resetMacro,
		`^\]\w+$`: endMacro,
	}

	needExec = map[string]bool{
		"[":       true,
		`^\]\w+$`: true,
	}
)

func searchWordCalcFunction(arg string) (cb calc.CalcFunc, ok bool) {
	for k, f := range wordCalcFunctions {
		if ok = regexp.MustCompile(k).MatchString(arg); ok {
			cb = f(arg[2:])
			break
		}
	}

	return
}

func searchIntCalcFunction(arg string) (cb calc.CalcFunc, ok bool) {
	for k, f := range intCalcFunctions {
		if ok = regexp.MustCompile(k).MatchString(arg); ok {
			var d uint64
			var err error
			if d, err = strconv.ParseUint(arg[1:], 10, 64); err != nil {
				d, _ = strconv.ParseUint(arg[2:], 10, 64)
			}
			cb = f(d)
			break
		}
	}

	return
}

func searchWordCliFunction(arg string) (cb CliFunc, ok, execNow bool) {
	for k, f := range wordCliFunctions {
		if ok = regexp.MustCompile(k).MatchString(arg); ok {
			if arg[0] == ']' {
				cb = f(arg[1:])
			} else {
				cb = f(arg[2:])
			}
			execNow = needExec[k]
			break
		}
	}

	return
}

func searchCalcFunction(arg string) (cb calc.CalcFunc, ok bool) {
	if cb, ok = calcFunctions[arg]; !ok {
		if cb, ok = searchWordCalcFunction(arg); !ok {
			cb, ok = searchIntCalcFunction(arg)
		}
	}

	return
}

func searchCliFunction(arg string) (cb CliFunc, ok, execNow bool) {
	if cb, ok = cliFunctions[arg]; !ok {
		cb, ok, execNow = searchWordCliFunction(arg)
	} else {
		execNow = needExec[arg]
	}

	return
}