// Package logging provides centralized structured logging using slog
// with configurable log levels. Call InitLogger() from main() to configure.
package logging

import (
	"io"
	"log/slog"
	"os"
	"strings"
)

// InitLogger initializes the global slog default logger with the specified log level.
// Valid levels: debug, info, warn, error (case-insensitive)
// If level is empty or invalid, defaults to INFO.
// Call this from main() at startup.
func InitLogger(level string) {
	var logLevel slog.Level

	switch strings.ToLower(strings.TrimSpace(level)) {
	case "debug":
		logLevel = slog.LevelDebug
	case "info", "":
		logLevel = slog.LevelInfo
	case "warn", "warning":
		logLevel = slog.LevelWarn
	case "error":
		logLevel = slog.LevelError
	default:
		logLevel = slog.LevelInfo
	}

	opts := &slog.HandlerOptions{
		Level: logLevel,
	}

	handler := slog.NewTextHandler(os.Stdout, opts)
	slog.SetDefault(slog.New(handler))
}

// SetupTestLogger configures logging for tests to reduce noise.
// Sets log level to WARN and outputs to io.Discard to suppress DEBUG and INFO messages.
// Returns a cleanup function that should be called when the test completes (use t.Cleanup).
func SetupTestLogger() func() {
	// Save original logger to restore later
	originalLogger := slog.Default()

	// Set level to WARN and discard output to silence tests
	opts := &slog.HandlerOptions{
		Level: slog.LevelWarn,
	}
	handler := slog.NewTextHandler(io.Discard, opts)
	slog.SetDefault(slog.New(handler))

	// Return cleanup function
	return func() {
		slog.SetDefault(originalLogger)
	}
}