package lagoon

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

type fillFixture struct {
	Name         string  `gorm:"column:name"`
	CollectionID uint    `gorm:"column:collection_id"`
	Notes        *string `gorm:"column:notes"`
}

func (fillFixture) Fillable() []string { return []string{"name", "notes"} }
func (fillFixture) Hidden() []string   { return []string{"collection_id"} }

var (
	_ HasFillable = fillFixture{}
	_ HasHidden   = fillFixture{}
)

func TestFillAllowList(t *testing.T) {
	var row fillFixture
	row.CollectionID = 3
	err := Fill(&row, []string{"name"}, map[string]any{
		"name":          "x",
		"collection_id": uint(9),
	}, true)
	if err != nil {
		t.Fatal(err)
	}
	if row.Name != "x" {
		t.Fatalf("name = %q", row.Name)
	}
	if row.CollectionID != 3 {
		t.Fatalf("collection_id mutated to %d", row.CollectionID)
	}
}

func TestFillDroppedKeyLogsOnce(t *testing.T) {
	var buf bytes.Buffer
	prev := slog.Default()
	slog.SetDefault(slog.New(slog.NewTextHandler(&buf, &slog.HandlerOptions{Level: slog.LevelWarn})))
	defer slog.SetDefault(prev)

	var row fillFixture
	requested := map[string]any{"name": "once", "collection_id": uint(1)}
	if err := Fill(&row, []string{"name"}, requested, false); err != nil {
		t.Fatal(err)
	}
	if err := Fill(&row, []string{"name"}, requested, false); err != nil {
		t.Fatal(err)
	}
	log := buf.String()
	if strings.Count(log, "collection_id") != 1 {
		t.Fatalf("dropped key should log once, got %q", log)
	}
	if !strings.Contains(log, "lagoon: dropped non-fillable key") {
		t.Fatalf("missing warn message: %q", log)
	}
}

func TestFillProductionSilent(t *testing.T) {
	var buf bytes.Buffer
	prev := slog.Default()
	slog.SetDefault(slog.New(slog.NewTextHandler(&buf, &slog.HandlerOptions{Level: slog.LevelWarn})))
	defer slog.SetDefault(prev)

	var row fillFixture
	if err := Fill(&row, []string{"name"}, map[string]any{
		"name":          "prod",
		"unknown_field": true,
	}, true); err != nil {
		t.Fatal(err)
	}
	if buf.Len() != 0 {
		t.Fatalf("production fill must be silent, got %q", buf.String())
	}
	if row.Name != "prod" {
		t.Fatalf("name = %q", row.Name)
	}
}

func TestFillNilPointerClearsNullable(t *testing.T) {
	existing := "keep"
	row := fillFixture{Notes: &existing}
	if err := Fill(&row, []string{"notes"}, map[string]any{"notes": nil}, true); err != nil {
		t.Fatal(err)
	}
	if row.Notes != nil {
		t.Fatalf("notes = %v, want nil", row.Notes)
	}
}

func TestFillDroppedKeyNeverErrors(t *testing.T) {
	var row fillFixture
	if err := Fill(&row, []string{"name"}, map[string]any{"collection_id": uint(9), "nope": 1}, true); err != nil {
		t.Fatalf("dropped keys must not error: %v", err)
	}
	if row.CollectionID != 0 {
		t.Fatalf("collection_id = %d", row.CollectionID)
	}
}