import { eq } from 'drizzle-orm';
import * as z from 'zod';
import {
    agents,
    files,
    models,
    providers,
    settings,
    toolCalls,
    topics,
    users,
} from '~~/drizzle/schema';
import { auth } from '~~/lib/auth';
import { db } from '~~/server/lib/db';

/**
 * Deletes the signed in user's account and everything that belongs to it.
 *
 * The app tables only store a plain user id, nothing cascades from the users
 * table, so every one of them is cleared here. It all happens in one
 * transaction: either the whole account is gone or nothing changed.
 *
 * Objects in file storage are left alone on purpose.
 */
export default defineEventHandler(async (event) => {
    await protectRoute(event);

    const userId = event.context.user!.id as string;

    const result = await readValidatedBody(event, (body) =>
        z
            .object({
                password: z.string().min(1),
                // required when two-factor is on: a code from the authenticator
                // app, or one of the backup codes
                code: z.string().min(1).optional(),
                backupCode: z.boolean().optional(),
            })
            .safeParse(body),
    );

    if (!result.success) {
        throw createError({
            statusCode: 400,
            message: result.error.issues[0]!.message,
        });
    }

    const { password, code, backupCode } = result.data;

    // read from the database, the session can lag behind by a few minutes
    const account = await db.query.users.findFirst({
        where: {
            id: userId,
        },
    });

    const twoFactorEnabled = !!account?.twoFactorEnabled;

    if (twoFactorEnabled && code === undefined) {
        throw createError({
            statusCode: 400,
            statusMessage: 'Two-factor code required',
            data: {
                code: 'TWO_FACTOR_REQUIRED',
            },
        });
    }

    try {
        await auth.api.verifyPassword({
            body: {
                password,
            },
            headers: event.headers,
        });

        if (twoFactorEnabled && backupCode) {
            await auth.api.verifyBackupCode({
                body: {
                    code: code!,
                },
                headers: event.headers,
            });
        } else if (twoFactorEnabled) {
            await auth.api.verifyTOTP({
                body: {
                    code: code!,
                },
                headers: event.headers,
            });
        }
    } catch (error: any) {
        const errorCode = error?.body?.code as string | undefined;

        if (errorCode === undefined) {
            console.error('Failed to verify credentials:', error);
        }

        throw createError({
            statusCode: errorCode === undefined ? 500 : 400,
            statusMessage: 'Failed to delete account',
            data: {
                code: errorCode ?? 'INTERNAL_ERROR',
            },
        });
    }

    await db.transaction(async (tx) => {
        // messages, their parts, generations and attachments cascade from topics
        await tx.delete(topics).where(eq(topics.userId, userId));
        await tx.delete(agents).where(eq(agents.userId, userId));
        await tx.delete(models).where(eq(models.userId, userId));
        await tx.delete(providers).where(eq(providers.userId, userId));
        // nothing points a tool call back at its message, so these never cascade
        await tx.delete(toolCalls).where(eq(toolCalls.userId, userId));
        // embeddings go with their file
        await tx.delete(files).where(eq(files.userId, userId));
        await tx.delete(settings).where(eq(settings.userId, userId));

        // sessions, accounts and two-factor rows cascade from the user
        await tx.delete(users).where(eq(users.id, userId));
    });

    // the session is gone, but the browser would keep trusting its cached
    // copy for a few minutes unless the cookies go too
    const { authCookies } = await auth.$context;

    for (const cookie of Object.values(authCookies)) {
        deleteCookie(event, cookie.name, {
            path: cookie.attributes.path,
            secure: cookie.attributes.secure,
            sameSite: cookie.attributes.sameSite,
            httpOnly: cookie.attributes.httpOnly,
        });
    }

    return { ok: true };
});