import type { PageServerLoad, Actions } from './$types';
import { db } from '$lib/server/db';
import { fosterAssignments, users } from '$lib/server/schema';
import { eq, and, asc } from 'drizzle-orm';
import { error, fail } from '@sveltejs/kit';
import { logAudit } from '$lib/server/audit';
import { hasPermission, canViewPets } from '$lib/roles';

export const load: PageServerLoad = async ({ parent, locals }) => {
	if (!canViewPets(locals.user!.role)) error(403, 'Access denied');
	const { pet } = await parent();

	const assignments = await db
		.select({
			id: fosterAssignments.id,
			petId: fosterAssignments.petId,
			userId: fosterAssignments.userId,
			startDate: fosterAssignments.startDate,
			endDate: fosterAssignments.endDate,
			isCurrent: fosterAssignments.isCurrent,
			notes: fosterAssignments.notes,
			createdAt: fosterAssignments.createdAt,
			fosterName: users.name,
			fosterEmail: users.email
		})
		.from(fosterAssignments)
		.leftJoin(users, eq(fosterAssignments.userId, users.id))
		.where(eq(fosterAssignments.petId, pet.id))
		.orderBy(asc(fosterAssignments.startDate));

	// Load active foster-role users for the dropdown
	const fosterUsers = await db
		.select({ id: users.id, name: users.name, email: users.email })
		.from(users)
		.where(and(eq(users.role, 'foster'), eq(users.active, true)))
		.orderBy(asc(users.name));

	return { assignments, fosterUsers };
};

export const actions: Actions = {
	add: async ({ request, params, locals }) => {
		if (!hasPermission(locals.user!.role, 'pets')) error(403, 'Access denied');
		const petId = parseInt(params.id, 10);
		const fd = await request.formData();

		const userIdStr = fd.get('userId')?.toString();
		const userId = userIdStr ? parseInt(userIdStr, 10) : null;

		if (!userId || isNaN(userId)) {
			return fail(400, { error: 'Foster user is required' });
		}

		const startDateStr = fd.get('startDate')?.toString() || null;
		const startDate = startDateStr ? new Date(startDateStr) : new Date();
		const endDateStr = fd.get('endDate')?.toString() || null;
		const endDate = endDateStr ? new Date(endDateStr) : null;
		const notes = fd.get('notes')?.toString().trim() || null;
		const isCurrent = fd.get('isCurrent') === 'on';

		// If marking as current, unset all others
		if (isCurrent) {
			await db.update(fosterAssignments).set({ isCurrent: false }).where(eq(fosterAssignments.petId, petId));
		}

		const [inserted] = await db.insert(fosterAssignments).values({
			petId,
			userId,
			startDate,
			endDate,
			notes,
			isCurrent
		}).$returningId();

		await logAudit({
			userId: locals.user!.id,
			action: 'create',
			entity: 'foster_assignment',
			entityId: inserted.id,
			diff: { petId, userId, isCurrent }
		});

		return { success: true };
	},

	setCurrent: async ({ request, params, locals }) => {
		if (!hasPermission(locals.user!.role, 'pets')) error(403, 'Access denied');
		const petId = parseInt(params.id, 10);
		const fd = await request.formData();
		const assignmentId = parseInt(fd.get('assignmentId') as string, 10);

		if (!assignmentId || isNaN(assignmentId)) {
			return fail(400, { error: 'Invalid assignment ID' });
		}

		const isCurrent = fd.get('isCurrent') === 'on';

		if (isCurrent) {
			await db.update(fosterAssignments).set({ isCurrent: false }).where(eq(fosterAssignments.petId, petId));
		}

		await db.update(fosterAssignments).set({ isCurrent }).where(eq(fosterAssignments.id, assignmentId));

		await logAudit({
			userId: locals.user!.id,
			action: 'update',
			entity: 'foster_assignment',
			entityId: assignmentId,
			diff: { petId, isCurrent }
		});

		return { success: true };
	},

	delete: async ({ request, params, locals }) => {
		if (!hasPermission(locals.user!.role, 'pets')) error(403, 'Access denied');
		const petId = parseInt(params.id, 10);
		const fd = await request.formData();
		const assignmentId = parseInt(fd.get('assignmentId') as string, 10);

		if (!assignmentId || isNaN(assignmentId)) {
			return fail(400, { error: 'Invalid assignment ID' });
		}

		await db.delete(fosterAssignments).where(eq(fosterAssignments.id, assignmentId));

		await logAudit({
			userId: locals.user!.id,
			action: 'delete',
			entity: 'foster_assignment',
			entityId: assignmentId,
			diff: { petId }
		});

		return { success: true };
	}
};