package log

import (
	"context"
	"fmt"
	"log/slog"
	"os"
	"path/filepath"
	"runtime"
	"strings"

	"golang.org/x/term"
)

// LogLevel represents the logging level
type LogLevel int

const (
	LevelFatal LogLevel = iota
	LevelError
	LevelWarn
	LevelNotice
	LevelInfo
	LevelDebug
)

// Logger configuration
type Config struct {
	Verbose bool
	Debug   bool
	Cron    bool
}

var logger *slog.Logger

// Initialize sets up the global logger based on the provided configuration
func Initialize(cfg Config) {
	// Determine log level based on configuration
	var level slog.Level

	if cfg.Cron {
		// In cron mode, only show fatal errors (which we'll handle specially)
		level = slog.LevelError
	} else if cfg.Debug || strings.Contains(os.Getenv("GODEBUG"), "vaultik") {
		level = slog.LevelDebug
	} else if cfg.Verbose {
		level = slog.LevelInfo
	} else {
		level = slog.LevelWarn
	}

	// Create handler with appropriate level
	opts := &slog.HandlerOptions{
		Level: level,
	}

	// Check if stdout is a TTY
	if term.IsTerminal(int(os.Stdout.Fd())) {
		// Use colorized TTY handler
		logger = slog.New(NewTTYHandler(os.Stdout, opts))
	} else {
		// Use JSON format for non-TTY output
		logger = slog.New(slog.NewJSONHandler(os.Stdout, opts))
	}

	// Set as default logger
	slog.SetDefault(logger)
}

// getCaller returns the caller information as a string
func getCaller(skip int) string {
	_, file, line, ok := runtime.Caller(skip)
	if !ok {
		return "unknown"
	}
	return fmt.Sprintf("%s:%d", filepath.Base(file), line)
}

// Fatal logs a fatal error and exits
func Fatal(msg string, args ...any) {
	if logger != nil {
		// Add caller info to args
		args = append(args, "caller", getCaller(2))
		logger.Error(msg, args...)
	}
	os.Exit(1)
}

// Fatalf logs a formatted fatal error and exits
func Fatalf(format string, args ...any) {
	Fatal(fmt.Sprintf(format, args...))
}

// Error logs an error
func Error(msg string, args ...any) {
	if logger != nil {
		args = append(args, "caller", getCaller(2))
		logger.Error(msg, args...)
	}
}

// Errorf logs a formatted error
func Errorf(format string, args ...any) {
	Error(fmt.Sprintf(format, args...))
}

// Warn logs a warning
func Warn(msg string, args ...any) {
	if logger != nil {
		args = append(args, "caller", getCaller(2))
		logger.Warn(msg, args...)
	}
}

// Warnf logs a formatted warning
func Warnf(format string, args ...any) {
	Warn(fmt.Sprintf(format, args...))
}

// Notice logs a notice (mapped to Info level)
func Notice(msg string, args ...any) {
	if logger != nil {
		args = append(args, "caller", getCaller(2))
		logger.Info(msg, args...)
	}
}

// Noticef logs a formatted notice
func Noticef(format string, args ...any) {
	Notice(fmt.Sprintf(format, args...))
}

// Info logs an info message
func Info(msg string, args ...any) {
	if logger != nil {
		args = append(args, "caller", getCaller(2))
		logger.Info(msg, args...)
	}
}

// Infof logs a formatted info message
func Infof(format string, args ...any) {
	Info(fmt.Sprintf(format, args...))
}

// Debug logs a debug message
func Debug(msg string, args ...any) {
	if logger != nil {
		args = append(args, "caller", getCaller(2))
		logger.Debug(msg, args...)
	}
}

// Debugf logs a formatted debug message
func Debugf(format string, args ...any) {
	Debug(fmt.Sprintf(format, args...))
}

// With returns a logger with additional context
func With(args ...any) *slog.Logger {
	if logger != nil {
		return logger.With(args...)
	}
	return slog.Default()
}

// WithContext returns a logger with context
func WithContext(ctx context.Context) *slog.Logger {
	return logger
}

// Logger returns the underlying slog.Logger
func Logger() *slog.Logger {
	return logger
}