/*
This Source Code Form is subject to the terms of the Mozilla Public
License, v. 2.0. If a copy of the MPL was not distributed with this
file, You can obtain one at https://mozilla.org/MPL/2.0/.
*/

package internal

import (
	"log"
	"os"
)

type LogLevel int

const (
	LogLevelSilent LogLevel = iota - 4
	LogLevelFatal
	LogLevelError
	LogLevelWarn
	LogLevelPrint
	LogLevelInfo
	LogLevelDebug
)

func NewLogger() *Logger {
	return &Logger{}
}

// TODO use separate debug logger with line number output
type Logger struct {
	parent *Logger
	level  LogLevel
	base   string
}

func (l *Logger) addBase(format string) string {
	if l.parent == nil {
		return format
	}
	return l.parent.addBase(format)
}

func (l *Logger) Level(level LogLevel) {
	l.level = level
}

func (l *Logger) Push(str string) *Logger {
	return &Logger{parent: l, base: str}
}

func (l *Logger) Print(format string, msg ...any) {
	l.logAs(LogLevelPrint, format, msg...)
}

func (l *Logger) Fatal(format string, msg ...any) {
	l.logAs(LogLevelFatal, l.addBase(format), msg...)
	os.Exit(1)
}

func (l *Logger) Error(format string, msg ...any) {
	l.logAs(LogLevelError, l.addBase(format), msg...)
}

func (l *Logger) Warn(format string, msg ...any) {
	l.logAs(LogLevelWarn, l.addBase(format), msg...)
}

func (l *Logger) Info(format string, msg ...any) {
	l.logAs(LogLevelInfo, l.addBase(format), msg...)
}

func (l *Logger) Debug(format string, msg ...any) {
	l.logAs(LogLevelDebug, l.addBase(format), msg...)
}

func (l *Logger) logAs(
	level LogLevel,
	format string,
	msg ...any,
) {
	if level > l.level {
		return
	}

	var pfx string
	switch level {
	case LogLevelFatal:
		pfx = "FATAL"
	case LogLevelError:
		pfx = "ERROR"
	case LogLevelWarn:
		pfx = "Warn"
	case LogLevelInfo:
		pfx = "info"
	case LogLevelDebug:
		pfx = "debug"
	}
	log.Printf(pfx+": "+format, msg...)
}