package db

import (
	"database/sql"
	"testing"
)

func TestNullStrPtr(t *testing.T) {
	tests := []struct {
		name     string
		input    sql.NullString
		wantNil  bool
		wantVal  string
	}{
		{
			name:    "valid string",
			input:   sql.NullString{String: "hello", Valid: true},
			wantNil: false,
			wantVal: "hello",
		},
		{
			name:    "invalid (nil)",
			input:   sql.NullString{Valid: false},
			wantNil: true,
		},
		{
			name:    "valid empty string",
			input:   sql.NullString{String: "", Valid: true},
			wantNil: false,
			wantVal: "",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := nullStrPtr(tt.input)
			if tt.wantNil {
				if got != nil {
					t.Errorf("nullStrPtr() = %v, want nil", got)
				}
				return
			}
			if got == nil {
				t.Fatal("nullStrPtr() = nil, want non-nil pointer")
			}
			if *got != tt.wantVal {
				t.Errorf("nullStrPtr() = %q, want %q", *got, tt.wantVal)
			}
		})
	}
}

func TestNullStrVal(t *testing.T) {
	tests := []struct {
		name  string
		input sql.NullString
		want  string
	}{
		{
			name:  "valid string",
			input: sql.NullString{String: "world", Valid: true},
			want:  "world",
		},
		{
			name:  "invalid (nil)",
			input: sql.NullString{Valid: false},
			want:  "",
		},
		{
			name:  "valid empty string",
			input: sql.NullString{String: "", Valid: true},
			want:  "",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := nullStrVal(tt.input)
			if got != tt.want {
				t.Errorf("nullStrVal() = %q, want %q", got, tt.want)
			}
		})
	}
}

func TestNullIntPtr(t *testing.T) {
	tests := []struct {
		name    string
		input   sql.NullInt64
		wantNil bool
		wantVal int
	}{
		{
			name:    "valid int",
			input:   sql.NullInt64{Int64: 42, Valid: true},
			wantNil: false,
			wantVal: 42,
		},
		{
			name:    "invalid (nil)",
			input:   sql.NullInt64{Valid: false},
			wantNil: true,
		},
		{
			name:    "valid zero",
			input:   sql.NullInt64{Int64: 0, Valid: true},
			wantNil: false,
			wantVal: 0,
		},
		{
			name:    "valid negative",
			input:   sql.NullInt64{Int64: -100, Valid: true},
			wantNil: false,
			wantVal: -100,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := nullIntPtr(tt.input)
			if tt.wantNil {
				if got != nil {
					t.Errorf("nullIntPtr() = %v, want nil", got)
				}
				return
			}
			if got == nil {
				t.Fatal("nullIntPtr() = nil, want non-nil pointer")
			}
			if *got != tt.wantVal {
				t.Errorf("nullIntPtr() = %d, want %d", *got, tt.wantVal)
			}
		})
	}
}