package level

import (
	"fmt"
	"strings"
)

// LEVEL defines a level of logging.
type LEVEL uint8

// Default levels of logging.
const (
	UNSET LEVEL = 0
	PANIC LEVEL = 1
	FATAL LEVEL = 50
	ERROR LEVEL = 100
	WARN  LEVEL = 150
	INFO  LEVEL = 200
	DEBUG LEVEL = 250
	TRACE LEVEL = 254
	ALL   LEVEL = ^LEVEL(0)
)

// CanLog returns whether an incoming log of 'lvl' can be logged against receiving level.
func (loglvl LEVEL) CanLog(lvl LEVEL) bool {
	return loglvl > lvl
}

// Levels defines a mapping of log LEVELs to formatted level strings.
type Levels [int(ALL) + 1]string

// Default returns the default set of log levels.
func Default() Levels {
	return Levels{
		TRACE: "TRACE",
		DEBUG: "DEBUG",
		INFO:  "INFO",
		WARN:  "WARN",
		ERROR: "ERROR",
		FATAL: "FATAL",
		PANIC: "PANIC",
	}
}

// Get fetches the level string for the provided value.
func (l Levels) Get(lvl LEVEL) string {
	return l[int(lvl)]
}

// Parse will attempt to decode a LEVEL from given string, checking (case insensitive) against strings in Levels.
func (l Levels) Parse(s string) (LEVEL, error) {
	// Ensure consistent casing
	s = strings.ToUpper(s)

	for lvl := LEVEL(0); int(lvl) < len(l); lvl++ {
		// Compare to eqach known level
		if strings.ToUpper(l[lvl]) == s {
			return lvl, nil
		}
	}

	return 0, fmt.Errorf("unrecognized log level: %s", s)
}