util.go

package table

import (
	"reflect"
)

// AutoIndexColumnID returns a unique Column ID/Name for the given Column Number.
// The functionality is similar to what you get in an Excel spreadsheet w.r.t.
// the Column ID/Name.
func AutoIndexColumnID(colIdx int) string {
	charIdx := colIdx % 26
	out := string(rune(65 + charIdx))
	colIdx = colIdx / 26
	if colIdx > 0 {
		return AutoIndexColumnID(colIdx-1) + out
	}
	return out
}

// WidthEnforcer is a function that helps enforce a width condition on a string.
type WidthEnforcer func(col string, maxLen int) string

// widthEnforcerNone returns the input string as is without any modifications.
func widthEnforcerNone(col string, _ int) string {
	return col
}

// isNumber returns true if the argument is a numeric type; false otherwise.
func isNumber(x interface{}) bool {
	if x == nil {
		return false
	}

	switch reflect.TypeOf(x).Kind() {
	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
		reflect.Float32, reflect.Float64:
		return true
	}
	return false
}

type mergedColumnIndices map[int]map[int]bool

func (m mergedColumnIndices) mergedLength(colIdx int, maxColumnLengths []int) int {
	mergedLength := maxColumnLengths[colIdx]
	for otherColIdx := range m[colIdx] {
		mergedLength += maxColumnLengths[otherColIdx]
	}
	return mergedLength
}

func (m mergedColumnIndices) len(colIdx int) int {
	return len(m[colIdx]) + 1
}

func (m mergedColumnIndices) safeAppend(colIdx, otherColIdx int) {
	// map
	if m[colIdx] == nil {
		m[colIdx] = make(map[int]bool)
	}
	m[colIdx][otherColIdx] = true

	// reverse map
	if m[otherColIdx] == nil {
		m[otherColIdx] = make(map[int]bool)
	}
	m[otherColIdx][colIdx] = true
}