// Package log provides a global logger for zerolog.
package log

import (
	"context"
	"net/http"
	"os"

	"github.com/rs/zerolog"
)

// Logger is the global logger.
var Logger = zerolog.New(os.Stdout).With().Timestamp().Logger()

// SetDebugMode tells the logger to use standard out and pretty print output.
func SetDebugMode() {
	Logger = Logger.Output(zerolog.ConsoleWriter{Out: os.Stdout})
}

// SetLevel sets the minimum global log level. Options are 'debu' 'info' 'warn' and 'error'.
// Defaults to 'debug'
func SetLevel(level string) {
	switch level {
	case "info":
		zerolog.SetGlobalLevel(zerolog.InfoLevel)
	case "warn":
		zerolog.SetGlobalLevel(zerolog.WarnLevel)
	case "error":
		zerolog.SetGlobalLevel(zerolog.ErrorLevel)
	default:
		zerolog.SetGlobalLevel(zerolog.DebugLevel)
	}
}

// With creates a child logger with the field added to its context.
func With() zerolog.Context {
	return Logger.With()
}

// Level creates a child logger with the minimum accepted level set to level.
func Level(level zerolog.Level) zerolog.Logger {
	return Logger.Level(level)
}

// Debug starts a new message with debug level.
//
// You must call Msg on the returned event in order to send the event.
func Debug() *zerolog.Event {
	return Logger.Debug()
}

// Info starts a new message with info level.
//
// You must call Msg on the returned event in order to send the event.
func Info() *zerolog.Event {
	return Logger.Info()
}

// Warn starts a new message with warn level.
//
// You must call Msg on the returned event in order to send the event.
func Warn() *zerolog.Event {
	return Logger.Warn()
}

// Error starts a new message with error level.
//
// You must call Msg on the returned event in order to send the event.
func Error() *zerolog.Event {
	return Logger.Error()
}

// Fatal starts a new message with fatal level. The os.Exit(1) function
// is called by the Msg method.
//
// You must call Msg on the returned event in order to send the event.
func Fatal() *zerolog.Event {
	return Logger.Fatal()
}

// Panic starts a new message with panic level. The message is also sent
// to the panic function.
//
// You must call Msg on the returned event in order to send the event.
func Panic() *zerolog.Event {
	return Logger.Panic()
}

// WithLevel starts a new message with level.
//
// You must call Msg on the returned event in order to send the event.
func WithLevel(level zerolog.Level) *zerolog.Event {
	return Logger.WithLevel(level)
}

// Log starts a new message with no level. Setting zerolog.GlobalLevel to
// zerolog.Disabled will still disable events produced by this method.
//
// You must call Msg on the returned event in order to send the event.
func Log() *zerolog.Event {
	return Logger.Log()
}

// Print sends a log event using debug level and no extra field.
// Arguments are handled in the manner of fmt.Print.
func Print(v ...interface{}) {
	Logger.Print(v...)
}

// Printf sends a log event using debug level and no extra field.
// Arguments are handled in the manner of fmt.Printf.
func Printf(format string, v ...interface{}) {
	Logger.Printf(format, v...)
}

// Ctx returns the Logger associated with the ctx. If no logger
// is associated, a disabled logger is returned.
func Ctx(ctx context.Context) *zerolog.Logger {
	return zerolog.Ctx(ctx)
}

// FromRequest gets the logger in the request's context.
// This is a shortcut for log.Ctx(r.Context())
func FromRequest(r *http.Request) *zerolog.Logger {
	return Ctx(r.Context())
}

// StdLogWrapper can be used to wrap logs originating from the from std
// library's ErrorFunction argument in http.Serve and httputil.ReverseProxy.
type StdLogWrapper struct {
	*zerolog.Logger
}

func (l *StdLogWrapper) Write(p []byte) (n int, err error) {
	n = len(p)
	if n > 0 && p[n-1] == '\n' {
		// Trim CR added by stdlog.
		p = p[0 : n-1]
	}
	l.Error().Msg(string(p))
	return len(p), nil
}