package db

import (
	"strings"
	"testing"
)

func TestSplitStatements(t *testing.T) {
	cases := []struct {
		in   string
		want []string
	}{
		{"SELECT 1", []string{"SELECT 1"}},
		{"SELECT 1; SELECT 2;", []string{"SELECT 1", "SELECT 2"}},
		{"SELECT ';'; SELECT 2", []string{"SELECT ';'", "SELECT 2"}},
		{"SELECT 1; -- c;mt\nSELECT 2", []string{"SELECT 1", "-- c;mt\nSELECT 2"}},
		{"/* a;b */ SELECT 1; SELECT 2", []string{"/* a;b */ SELECT 1", "SELECT 2"}},
		{`SELECT "a;b"; SELECT 2`, []string{`SELECT "a;b"`, "SELECT 2"}},
		{";;", nil},
		{"", nil},
	}
	for _, tc := range cases {
		got := SplitStatements(tc.in)
		if len(got) != len(tc.want) {
			t.Fatalf("SplitStatements(%q) = %#v, want %#v", tc.in, got, tc.want)
		}
		for i := range got {
			if got[i] != tc.want[i] {
				t.Fatalf("SplitStatements(%q)[%d] = %q, want %q", tc.in, i, got[i], tc.want[i])
			}
		}
	}
}

func TestStripComments(t *testing.T) {
	cases := []struct {
		in      string
		has     string // 结果应包含(大小写敏感原文)
		missing string // 结果不应包含
	}{
		{"SELECT 1 -- WHERE x", "SELECT 1", "WHERE x"},
		{"UPDATE t SET x=1 # note\nWHERE id=1", "WHERE id=1", "note"},
		{"SELECT /* hint */ 1", "SELECT", "hint"},
		{"SELECT /*!50000 DROP TABLE t*/", "DROP TABLE t", "/*!"},
		{"SELECT 'DROP TABLE x'", "SELECT", "DROP TABLE x"},
		{`SELECT "col;drop" FROM t`, "FROM t", "col;drop"},
	}
	for _, tc := range cases {
		got := StripComments(tc.in)
		if tc.has != "" && !strings.Contains(got, tc.has) {
			t.Fatalf("StripComments(%q) = %q, 应包含 %q", tc.in, got, tc.has)
		}
		if tc.missing != "" && strings.Contains(got, tc.missing) {
			t.Fatalf("StripComments(%q) = %q, 不应包含 %q", tc.in, got, tc.missing)
		}
	}
}