package cabana

import (
	"reflect"
	"testing"
	"time"

	"gorm.io/gorm"
)

type embeddedBase struct {
	ID        uint      `gorm:"primarykey"`
	CreatedAt time.Time `gorm:"column:created_at"`
}

type embeddedModel struct {
	embeddedBase
	Name string `gorm:"column:name"`
}

type gormModelRow struct {
	gorm.Model
	Name string `gorm:"column:name"`
}

type retaggedModel struct {
	Name  string `gorm:"column:title"`
	Title string `gorm:"column:name"`
	Plain string
}

// TestModelHelpersLookThroughEmbeddedStructs pins WR-16: the reflection helpers
// that resolve columns see fields promoted from an embedded struct such as
// gorm.Model, so list rows keep their id and timestamps and a relation link
// writes the real owner key instead of 0.
func TestModelHelpersLookThroughEmbeddedStructs(t *testing.T) {
	row := &embeddedModel{embeddedBase: embeddedBase{ID: 7, CreatedAt: time.Unix(1700000000, 0).UTC()}, Name: "n"}
	if got := primaryColumn(row); got != "id" {
		t.Fatalf("primaryColumn = %q, want id (the embedded primarykey field)", got)
	}
	if got := pkUint(row); got != 7 {
		t.Fatalf("pkUint = %d, want 7", got)
	}
	cols := modelColumns(row)
	for _, want := range []string{"created_at", "name"} {
		if _, ok := cols[want]; !ok {
			t.Fatalf("modelColumns = %v, missing %s", cols, want)
		}
	}
	projected := projectRow(row, nil, []ListColumn{{Key: "name"}, {Key: "created_at"}})
	if projected["id"] != uint(7) || projected["name"] != "n" || projected["created_at"] == nil {
		t.Fatalf("projectRow = %#v, want the embedded id and created_at", projected)
	}
	if castPK(row, 9) != uint(9) {
		t.Fatalf("castPK = %#v", castPK(row, 9))
	}

	gm := &gormModelRow{Model: gorm.Model{ID: 11}, Name: "g"}
	if primaryColumn(gm) != "id" || pkUint(gm) != 11 {
		t.Fatalf("gorm.Model primary key = %q/%d, want id/11", primaryColumn(gm), pkUint(gm))
	}
	if !fieldByColumn(reflect.ValueOf(gm).Elem(), "updated_at").IsValid() {
		t.Fatal("gorm.Model's UpdatedAt is not reachable by column")
	}
}

// TestFieldByColumnTagBeatsGoName pins the other half of WR-16: a field with an
// explicit column tag is matched by that tag alone, never by its Go name.
func TestFieldByColumnTagBeatsGoName(t *testing.T) {
	row := retaggedModel{Name: "in-title-column", Title: "in-name-column", Plain: "p"}
	v := reflect.ValueOf(row)
	if got := fieldByColumn(v, "name"); !got.IsValid() || got.String() != "in-name-column" {
		t.Fatalf("column name resolved to %v, want the field tagged column:name", got)
	}
	if got := fieldByColumn(v, "title"); !got.IsValid() || got.String() != "in-title-column" {
		t.Fatalf("column title resolved to %v, want the field tagged column:title", got)
	}
	if got := fieldByColumn(v, "plain"); !got.IsValid() || got.String() != "p" {
		t.Fatalf("an untagged field must still match its Go name case-insensitively, got %v", got)
	}
	if got := fieldByColumn(reflect.ValueOf(struct {
		Name string `gorm:"column:title"`
	}{Name: "x"}), "name"); got.IsValid() {
		t.Fatalf("a tagged field matched by its Go name: %v", got)
	}
}