package lagoon

import (
	"bytes"
	"encoding/json"
	"errors"
	"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)
	}
}

type fillSecretFixture struct {
	Name   string     `gorm:"column:name"`
	APIKey Encrypted  `gorm:"column:api_key" json:"-"`
	Token  *Encrypted `gorm:"column:token" json:"-"`
}

func TestFillEncryptedTakesPlaintext(t *testing.T) {
	if err := PublishEncryptionKeys(nil, bytes.Repeat([]byte("F"), 32), nil); err != nil {
		t.Fatal(err)
	}
	allowed := []string{"name", "api_key", "token"}
	var row fillSecretFixture
	if err := Fill(&row, allowed, map[string]any{"api_key": "sk-plain", "token": "tok-plain"}, true); err != nil {
		t.Fatal(err)
	}
	if row.APIKey.Reveal() != "sk-plain" {
		t.Fatalf("api_key Reveal = %q", row.APIKey.Reveal())
	}
	if row.Token == nil || row.Token.Reveal() != "tok-plain" {
		t.Fatalf("token = %v", row.Token)
	}

	// Another row's ciphertext is stored as literal text, never decrypted.
	stolen, err := NewEncrypted("victim-secret").Value()
	if err != nil {
		t.Fatal(err)
	}
	ciphertext, ok := stolen.(string)
	if !ok {
		t.Fatalf("ciphertext driver value is %T", stolen)
	}
	var thief fillSecretFixture
	if err := Fill(&thief, allowed, map[string]any{"api_key": ciphertext}, true); err != nil {
		t.Fatal(err)
	}
	if thief.APIKey.Reveal() != ciphertext {
		t.Fatal("ciphertext in a request must not be decrypted into the victim's plaintext")
	}

	for _, bad := range []any{42, true, map[string]any{"x": 1}, []byte("raw")} {
		var r fillSecretFixture
		if err := Fill(&r, allowed, map[string]any{"api_key": bad}, true); err == nil {
			t.Fatalf("api_key=%T must be rejected", bad)
		}
		if r.APIKey.Reveal() != "" {
			t.Fatalf("api_key=%T left a value behind", bad)
		}
	}

	if err := Fill(&row, allowed, map[string]any{"api_key": nil, "token": nil}, true); err != nil {
		t.Fatal(err)
	}
	if row.APIKey.Reveal() != "" || row.Token != nil {
		t.Fatalf("nil must clear: api_key=%q token=%v", row.APIKey.Reveal(), row.Token)
	}
}

// TestFillJSONNumber covers request bodies decoded with UseNumber: a
// json.Number fills integer, unsigned and float fields (plain or pointer), a
// string field keeps the number's text, and a fraction or an overflow into an
// integer field is an error rather than a silent truncation.
func TestFillJSONNumber(t *testing.T) {
	type numbers struct {
		Year  *int    `gorm:"column:year"`
		Count uint8   `gorm:"column:count"`
		Price float64 `gorm:"column:price"`
		Code  string  `gorm:"column:code"`
	}
	allowed := []string{"year", "count", "price", "code"}
	var row numbers
	err := Fill(&row, allowed, map[string]any{
		"year":  json.Number("1977"),
		"count": json.Number("200"),
		"price": json.Number("12.5"),
		"code":  json.Number("0042"),
	}, true)
	if err != nil {
		t.Fatal(err)
	}
	if row.Year == nil || *row.Year != 1977 || row.Count != 200 || row.Price != 12.5 || row.Code != "0042" {
		t.Fatalf("row = %+v (year %v)", row, row.Year)
	}
	for key, value := range map[string]json.Number{"year": "1977.5", "count": "256"} {
		if err := Fill(&row, allowed, map[string]any{key: value}, true); err == nil {
			t.Fatalf("%s = %s filled without an error", key, value)
		}
	}
}

// TestFillTypeErrorNamesTheKey proves a value that does not fit its column
// comes back as a *FillTypeError carrying the requested key, so a caller can
// answer it as a validation failure on that field, while a bad model stays a
// plain error.
func TestFillTypeErrorNamesTheKey(t *testing.T) {
	type numbers struct {
		Year  int     `gorm:"column:year"`
		Count uint8   `gorm:"column:count"`
		Title string  `gorm:"column:title"`
		Price float64 `gorm:"column:price"`
	}
	allowed := []string{"year", "count", "title", "price"}
	cases := map[string]any{
		"year":  json.Number("1977.5"),
		"count": json.Number("1e21"),
		"title": true,
		"price": "cheap",
	}
	for key, value := range cases {
		var row numbers
		err := Fill(&row, allowed, map[string]any{key: value}, true)
		var typed *FillTypeError
		if !errors.As(err, &typed) || typed.Key != key || typed.Err == nil {
			t.Fatalf("%s = %v: err = %#v, want *FillTypeError for %s", key, value, err, key)
		}
		if !strings.Contains(err.Error(), "lagoon: fill "+key+": ") {
			t.Fatalf("%s: message = %q", key, err.Error())
		}
	}
	var typed *FillTypeError
	if err := Fill(numbers{}, allowed, map[string]any{"year": 1}, true); err == nil || errors.As(err, &typed) {
		t.Fatalf("non-pointer model: err = %v, want a plain error", err)
	}
}