package webutil

import (
	"net/url"
	"testing"
)

func TestScanStruct(t *testing.T) {
	t.Run("fields scanned by name", func(t *testing.T) {
		type S struct {
			Name   string
			Age    int
			Active bool
		}
		var s S
		err := ScanStruct(url.Values{
			"Name":   {"Alice"},
			"Age":    {"30"},
			"Active": {"on"},
		}, &s)
		if err != nil {
			t.Fatal(err)
		}
		if s.Name != "Alice" || s.Age != 30 || !s.Active {
			t.Fatalf("unexpected: %+v", s)
		}
	})

	t.Run("missing form key leaves zero value", func(t *testing.T) {
		type S struct {
			Name string
			Age  int
		}
		var s S
		if err := ScanStruct(url.Values{"Name": {"Bob"}}, &s); err != nil {
			t.Fatal(err)
		}
		if s.Name != "Bob" || s.Age != 0 {
			t.Fatalf("unexpected: %+v", s)
		}
	})

	t.Run("extra form keys ignored", func(t *testing.T) {
		type S struct{ Name string }
		var s S
		if err := ScanStruct(url.Values{"Name": {"Alice"}, "Extra": {"ignored"}}, &s); err != nil {
			t.Fatal(err)
		}
	})

	t.Run("unexported fields skipped", func(t *testing.T) {
		type S struct {
			Name   string
			secret string
		}
		var s S
		if err := ScanStruct(url.Values{"Name": {"Alice"}, "secret": {"oops"}}, &s); err != nil {
			t.Fatal(err)
		}
		if s.secret != "" {
			t.Fatal("unexported field should not be set")
		}
	})

	t.Run("parse error", func(t *testing.T) {
		type S struct{ Age int }
		var s S
		if err := ScanStruct(url.Values{"Age": {"not-a-number"}}, &s); err == nil {
			t.Fatal("expected error")
		}
	})

	t.Run("requires pointer to struct", func(t *testing.T) {
		if err := ScanStruct(url.Values{}, "not a struct"); err == nil {
			t.Fatal("expected error")
		}
	})
}