package logic

import "testing"

// TestResolveSort_WhitelistHit 白名单命中的列应原样返回，方向按 asc/desc 归一。
func TestResolveSort_WhitelistHit(t *testing.T) {
	wl := map[string]string{"created_at": "created_at", "usage_count": "usage_count"}

	col, dir := resolveSort("created_at", "asc", wl, "id desc")
	if col != "created_at" || dir != "asc" {
		t.Fatalf("hit asc: got (%q,%q)", col, dir)
	}

	// 方向大写也应被识别
	col, dir = resolveSort("usage_count", "ASC", wl, "id desc")
	if col != "usage_count" || dir != "asc" {
		t.Fatalf("hit ASC: got (%q,%q)", col, dir)
	}
}

// TestResolveSort_DefaultDirection 命中白名单但未给方向时，默认 desc。
func TestResolveSort_DefaultDirection(t *testing.T) {
	wl := map[string]string{"created_at": "created_at"}
	col, dir := resolveSort("created_at", "", wl, "id desc")
	if col != "created_at" || dir != "desc" {
		t.Fatalf("default dir: got (%q,%q)", col, dir)
	}
}

// TestResolveSort_FallbackParsed fallback 形如 "列名 方向" 时按解析结果返回。
func TestResolveSort_FallbackParsed(t *testing.T) {
	wl := map[string]string{"created_at": "created_at"}

	col, dir := resolveSort("", "", wl, "id desc")
	if col != "id" || dir != "desc" {
		t.Fatalf("empty sortBy fallback: got (%q,%q)", col, dir)
	}

	col, dir = resolveSort("nope", "", wl, "sort asc")
	if col != "sort" || dir != "asc" {
		t.Fatalf("unknown sortBy fallback: got (%q,%q)", col, dir)
	}

	// 只有列名、无方向时默认 desc
	col, dir = resolveSort("", "", wl, "sort")
	if col != "sort" || dir != "desc" {
		t.Fatalf("single-token fallback: got (%q,%q)", col, dir)
	}
}

// TestResolveSort_InjectionRejected 非法 sortBy（未在白名单）必须回落到 fallback，
// 绝不能把用户输入拼进 ORDER BY。
func TestResolveSort_InjectionRejected(t *testing.T) {
	wl := map[string]string{"created_at": "created_at"}

	for _, evil := range []string{
		"created_at; DROP TABLE users",
		"id)--",
		"(SELECT 1)",
		"created_at DESC, id",
	} {
		col, _ := resolveSort(evil, "asc", wl, "id desc")
		if col != "id" {
			t.Fatalf("injection %q not rejected, got col=%q", evil, col)
		}
	}
}