package logging

import (
	"log/slog"
	"strings"
	"testing"
)

func TestParseLevel(t *testing.T) {
	cases := []struct {
		in   string
		want slog.Level
		ok   bool
	}{
		{"debug", slog.LevelDebug, true},
		{"DEBUG", slog.LevelDebug, true},
		{" info ", slog.LevelInfo, true},
		{"warn", slog.LevelWarn, true},
		{"warning", slog.LevelWarn, true},
		{"error", slog.LevelError, true},
		{"trace", 0, false},
		{"", 0, false},
	}
	for _, c := range cases {
		got, err := ParseLevel(c.in)
		if c.ok && err != nil {
			t.Errorf("ParseLevel(%q) unexpected error: %v", c.in, err)
		}
		if !c.ok && err == nil {
			t.Errorf("ParseLevel(%q) expected error, got %v", c.in, got)
		}
		if c.ok && got != c.want {
			t.Errorf("ParseLevel(%q) = %v, want %v", c.in, got, c.want)
		}
	}
}

func TestParseFormat(t *testing.T) {
	cases := []struct {
		in   string
		want string
		ok   bool
	}{
		{"", "json", true},
		{"json", "json", true},
		{"TEXT", "text", true},
		{" text ", "text", true},
		{"xml", "", false},
	}
	for _, c := range cases {
		got, err := ParseFormat(c.in)
		if c.ok && err != nil {
			t.Errorf("ParseFormat(%q) unexpected error: %v", c.in, err)
		}
		if !c.ok && err == nil {
			t.Errorf("ParseFormat(%q) expected error, got %q", c.in, got)
		}
		if c.ok && got != c.want {
			t.Errorf("ParseFormat(%q) = %q, want %q", c.in, got, c.want)
		}
	}
}

func TestRequestIDHelpers(t *testing.T) {
	if !ValidRequestID("req-abc_123.4") {
		t.Error("ValidRequestID(valid) = false")
	}
	for _, bad := range []string{"", "has space", "has\nnewline", "semi;colon", strings.Repeat("a", 129)} {
		if ValidRequestID(bad) {
			t.Errorf("ValidRequestID(%q) = true, want false", bad)
		}
	}
	id := NewRequestID()
	if id == "" || !ValidRequestID(id) {
		t.Fatalf("NewRequestID() = %q, want a valid non-empty id", id)
	}
	if NewRequestID() == id {
		t.Fatal("NewRequestID() returned the same value twice")
	}
}

func TestNewHandler(t *testing.T) {
	for _, format := range []string{"", "json", "JSON", "text"} {
		h, err := NewHandler(format, slog.LevelInfo)
		if err != nil {
			t.Errorf("NewHandler(%q) unexpected error: %v", format, err)
		}
		if h == nil {
			t.Errorf("NewHandler(%q) returned nil handler", format)
		}
	}
	if _, err := NewHandler("xml", slog.LevelInfo); err == nil {
		t.Error("NewHandler(\"xml\") expected error, got nil")
	}
}