package db

import (
	"context"
	"crypto/sha256"
	"fmt"
	"testing"
	"time"

	"github.com/stretchr/testify/require"

	"github.com/tamakyi/TamaBox/internal/conf"
)

func setR2TestConfig(t *testing.T) {
	t.Helper()
	oldBucket := conf.Upload.ImageBucket
	oldCDNHost := conf.Upload.ImageBucketCDNHost
	conf.Upload.ImageBucket = "test-r2-bucket"
	conf.Upload.ImageBucketCDNHost = "cdn.example.test/assets"
	oldDefaults := []string{conf.Upload.DefaultAvatarURL, conf.Upload.DefaultBackground, conf.Upload.DefaultBackgroundImageURL}
	conf.Upload.DefaultAvatarURL = "https://cdn.example.test/assets/default-avatar.webp"
	conf.Upload.DefaultBackground = "https://cdn.example.test/assets/default-background.webp"
	conf.Upload.DefaultBackgroundImageURL = "https://cdn.example.test/assets/default-qr.webp"
	t.Cleanup(func() {
		conf.Upload.DefaultAvatarURL, conf.Upload.DefaultBackground, conf.Upload.DefaultBackgroundImageURL = oldDefaults[0], oldDefaults[1], oldDefaults[2]
		conf.Upload.ImageBucket = oldBucket
		conf.Upload.ImageBucketCDNHost = oldCDNHost
	})
}

func TestR2DeleteTaskStore(t *testing.T) {
	setR2TestConfig(t)
	conn, _ := newTestDB(t)
	ctx := context.Background()
	store := NewR2DeleteTaskStore(conn)

	require.NoError(t, store.Enqueue(ctx, "", []string{"ignored.webp"}))
	require.NoError(t, store.Enqueue(ctx, conf.Upload.ImageBucket, nil))
	require.NoError(t, store.Enqueue(ctx, conf.Upload.ImageBucket, []string{
		"2026/11/shared.webp", "2026/11/shared.webp", "2026/11/other.webp", "",
	}))

	tasks, err := store.ListDue(ctx, 10)
	require.NoError(t, err)
	require.Len(t, tasks, 2)
	byKey := make(map[string]*R2DeleteTask, len(tasks))
	for _, task := range tasks {
		byKey[task.Key] = task
		require.Equal(t, conf.Upload.ImageBucket, task.Bucket)
		require.Len(t, task.KeyHash, 64)
	}
	shared := byKey["2026/11/shared.webp"]
	other := byKey["2026/11/other.webp"]
	require.NotNil(t, shared)
	require.NotNil(t, other)
	require.Equal(t, fmt.Sprintf("%x", sha256.Sum256([]byte(shared.Key))), shared.KeyHash)

	future := time.Now().Add(time.Hour).Truncate(time.Microsecond)
	require.NoError(t, store.MarkFailed(shared.ID, future, "temporary failure"))
	due, err := store.ListDue(ctx, 10)
	require.NoError(t, err)
	require.Len(t, due, 1)
	require.Equal(t, other.ID, due[0].ID)

	require.NoError(t, store.Enqueue(ctx, conf.Upload.ImageBucket, []string{shared.Key, shared.Key}))
	var requeued R2DeleteTask
	require.NoError(t, conn.WithContext(ctx).First(&requeued, shared.ID).Error)
	require.Equal(t, shared.ID, requeued.ID)
	require.Zero(t, requeued.Attempts)
	require.Empty(t, requeued.LastError)
	require.WithinDuration(t, time.Now(), requeued.NextRetryAt, 5*time.Second)

	// 同一个 key 可在不同 bucket 各有一条任务，但同一 bucket 内仍保持唯一。
	require.NoError(t, store.Enqueue(ctx, "another-bucket", []string{shared.Key}))
	var count int64
	require.NoError(t, conn.WithContext(ctx).Model(&R2DeleteTask{}).Count(&count).Error)
	require.Equal(t, int64(3), count)

	require.NoError(t, store.Delete(other.ID))
	require.NoError(t, conn.WithContext(ctx).Model(&R2DeleteTask{}).Count(&count).Error)
	require.Equal(t, int64(2), count)
	empty, err := store.ListDue(ctx, 0)
	require.NoError(t, err)
	require.NotNil(t, empty)
	require.Empty(t, empty)
}

func TestR2DeleteTaskHasReferences(t *testing.T) {
	setR2TestConfig(t)
	conn, _ := newTestDB(t)
	ctx := context.Background()
	store := NewR2DeleteTaskStore(conn)
	bucket := conf.Upload.ImageBucket

	upload := &UploadImage{Key: "upload.webp"}
	require.NoError(t, conn.WithContext(ctx).Create(upload).Error)
	require.NoError(t, conn.WithContext(ctx).Delete(upload).Error)
	referenced, err := store.HasReferences(ctx, bucket, upload.Key)
	require.NoError(t, err)
	require.True(t, referenced, "软删除的 upload_images 仍必须通过 Unscoped 阻止对象删除")

	message := &MessageImage{MessageID: 1, ObjectKey: "message.webp", URL: "https://cdn.example.test/assets/message.webp"}
	require.NoError(t, conn.WithContext(ctx).Create(message).Error)
	require.NoError(t, conn.WithContext(ctx).Delete(message).Error)
	referenced, err = store.HasReferences(ctx, bucket, message.ObjectKey)
	require.NoError(t, err)
	require.True(t, referenced, "软删除的 message_images 仍必须通过 Unscoped 阻止对象删除")

	legacyMessage := &MessageImage{MessageID: 2, URL: "https://cdn.example.test/assets/legacy-message.webp"}
	legacyUpload := &UploadImage{Key: "https://cdn.example.test/assets/legacy-upload.webp"}
	external := &MessageImage{MessageID: 3, URL: "https://external.example.net/external.webp"}
	require.NoError(t, conn.WithContext(ctx).Create(legacyMessage).Error)
	require.NoError(t, conn.WithContext(ctx).Create(legacyUpload).Error)
	require.NoError(t, conn.WithContext(ctx).Create(external).Error)

	for _, key := range []string{"legacy-message.webp", "legacy-upload.webp"} {
		referenced, err = store.HasReferences(ctx, bucket, key)
		require.NoError(t, err)
		require.True(t, referenced, key)
	}
	referenced, err = store.HasReferences(ctx, bucket, "external.webp")
	require.NoError(t, err)
	require.False(t, referenced)
	referenced, err = store.HasReferences(ctx, bucket, "missing.webp")
	require.NoError(t, err)
	require.False(t, referenced)

	profileUser := &User{Avatar: "https://cdn.example.test/assets/profile-avatar.webp", Background: "profile-background.webp", BackgroundImage: "https://external.example.net/external-profile.webp"}
	require.NoError(t, conn.WithContext(ctx).Create(profileUser).Error)
	for _, key := range []string{"profile-avatar.webp", "profile-background.webp", "default-avatar.webp", "default-background.webp", "default-qr.webp"} {
		referenced, err = store.HasReferences(ctx, bucket, key)
		require.NoError(t, err)
		require.True(t, referenced, key)
	}

	// 第二个引用查询失败时必须显式返回错误，不能误报为无引用。
	require.NoError(t, conn.Migrator().DropTable(&MessageImage{}))
	_, err = store.HasReferences(ctx, bucket, "missing-again.webp")
	require.Error(t, err)
}