package xmlmodels

import (
	"encoding/xml"
	"strconv"
	"strings"
)

func isASCIISpaceByte(b byte) bool {
	return b == ' ' || b == '\t' || b == '\n' || b == '\r'
}

func trimLeftASCIISpace(s string) string {
	i := 0
	for i < len(s) && isASCIISpaceByte(s[i]) {
		i++
	}
	return s[i:]
}

func trimRightASCIISpace(s string) string {
	i := len(s)
	for i > 0 && isASCIISpaceByte(s[i-1]) {
		i--
	}
	return s[:i]
}

func trimASCIISpace(s string) string {
	return trimRightASCIISpace(trimLeftASCIISpace(s))
}

func isOnlyASCIISpace(s string) bool {
	if len(s) == 0 {
		return true
	}
	for i := 0; i < len(s); i++ {
		if !isASCIISpaceByte(s[i]) {
			return false
		}
	}
	return true
}

func attrsToMap(attrs []xml.Attr) map[string]string {
	if len(attrs) == 0 {
		return nil
	}
	m := make(map[string]string, len(attrs))
	for _, a := range attrs {
		m[a.Name.Local] = a.Value
	}
	return m
}

// INFO: list of tags ignored
func isTransparentWrapper(name string) bool {
	return name == "tabs" || name == "address"
}

func parseLineMarker(se xml.StartElement) (LineType, int, bool) {
	var (
		indent int
		typ    string
	)
	for _, a := range se.Attr {
		switch a.Name.Local {
		case "tab":
			if n, err := strconv.Atoi(trimASCIISpace(a.Value)); err == nil && n > 0 {
				indent = n
			}
		case "type":
			typ = strings.ToLower(trimASCIISpace(a.Value))
		}
	}
	if typ == "empty" {
		return Empty, 0, true
	}
	if indent > 0 {
		return Indent, indent, false
	}

	// INFO: we don't check for break here, it's the default
	return Semantic, 0, false
}