import { json, error } from '@sveltejs/kit';
import type { RequestHandler } from './$types.js';
import { boardSchema } from '$lib/server/validation.js';
import { withTenant } from '$lib/server/rls.js';
import { requireAuth } from '$lib/server/guards.js';
import { prisma } from '$lib/server/db.js';
import { generatePositions } from '$lib/utils/fractional-index.js';

// List boards for current tenant
export const GET: RequestHandler = async ({ locals }) => {
	const tenant = locals.tenant;
	if (!tenant) throw error(400, 'Unknown tenant');

	const boards = await withTenant(tenant.id, async (tx) => {
		const where: Record<string, unknown> = { tenantId: tenant.id, archived: false };

		// If not logged in, only show public boards
		if (!locals.user) {
			where.visibility = 'PUBLIC';
		} else {
			// Show boards user is a member of + public boards
			where.OR = [
				{ visibility: 'PUBLIC' },
				{ members: { some: { userId: locals.user.id } } }
			];
		}

		return tx.board.findMany({
			where,
			include: {
				members: {
					include: { user: { select: { id: true, name: true, avatarUrl: true } } }
				},
				_count: { select: { columns: true } }
			},
			orderBy: { updatedAt: 'desc' }
		});
	});

	return json({ boards });
};

// Create a new board
export const POST: RequestHandler = async ({ request, locals }) => {
	const tenant = locals.tenant;
	if (!tenant) throw error(400, 'Unknown tenant');
	requireAuth(locals.user);

	const body = await request.json();
	const result = boardSchema.safeParse(body);
	if (!result.success) {
		return json({ error: result.error.issues[0].message }, { status: 400 });
	}

	const { title, description, visibility, categoryId, templateId } = result.data;
	const cardPrefix = title.replace(/[^a-zA-Z]/g, '').toUpperCase().slice(0, 4) || 'CARD';

	// Load template columns if templateId provided
	let templateColumns: { title: string }[] = [];
	if (templateId) {
		// System templates have null tenantId, so query without RLS
		const template = await prisma.boardTemplate.findFirst({
			where: {
				id: templateId,
				OR: [{ tenantId: null }, { tenantId: tenant.id }]
			}
		});
		if (template) {
			const tpl = template.template as { columns?: { title: string }[] };
			templateColumns = tpl.columns || [];
		}
	}

	const board = await withTenant(tenant.id, async (tx) => {
		const newBoard = await tx.board.create({
			data: {
				tenantId: tenant.id,
				title,
				description,
				visibility,
				cardPrefix,
				...(categoryId ? { categoryId } : {}),
				members: {
					create: {
						userId: locals.user!.id,
						role: 'OWNER'
					}
				}
			},
			include: {
				members: {
					include: { user: { select: { id: true, name: true, avatarUrl: true } } }
				}
			}
		});

		// Create columns from template
		if (templateColumns.length > 0) {
			const positions = generatePositions(templateColumns.length);
			for (let i = 0; i < templateColumns.length; i++) {
				await tx.column.create({
					data: {
						boardId: newBoard.id,
						title: templateColumns[i].title,
						position: positions[i]
					}
				});
			}
		}

		return newBoard;
	});

	return json({ board }, { status: 201 });
};