import type { PageServerLoad, Actions } from './$types';
import { redirect } from '@sveltejs/kit';
import { apiClient } from '$lib/server/api';
import { getWeekStart } from '$lib/planner/week';

export const load: PageServerLoad = async ({ fetch, url, locals: _locals }) => {
	const weekParam = url.searchParams.get('week');
	const weekStart = weekParam ?? getWeekStart(new Date());
	const selectedDay = url.searchParams.get('day') ?? weekStart;

	const api = apiClient(fetch);

	// Load the week plan for context (week-so-far display)
	const { data: weekPlan, error: weekPlanError } = await api.GET('/v1/week-plans', {
		params: { query: { weekStart } }
	});

	if (weekPlanError || !weekPlan?.id) {
		return { weekPlan: null, suggestions: [], selectedDay, weekStart };
	}

	// Load variety-aware suggestions for the selected day
	const { data: suggestionsData } = await api.GET('/v1/week-plans/{id}/suggestions', {
		params: { path: { id: weekPlan.id }, query: { slotDate: selectedDay } }
	});

	// Sort by simulatedScore descending (highest = best variety fit)
	const suggestions = (suggestionsData?.suggestions ?? []).sort(
		(a: any, b: any) => (b.simulatedScore ?? 0) - (a.simulatedScore ?? 0)
	);

	return { weekPlan, suggestions, selectedDay, weekStart };
};

export const actions: Actions = {
	pickSuggestion: async ({ fetch, request, locals }) => {
		// Role guard: only planners may assign meals
		if (locals.benutzer?.rolle !== 'planer') {
			return { success: false, error: 'Keine Berechtigung.' };
		}

		const formData = await request.formData();
		const planId = formData.get('planId') as string;
		const recipeId = formData.get('recipeId') as string;
		const slotDate = formData.get('slotDate') as string;
		const weekStart = formData.get('weekStart') as string;

		// Validate slotDate format
		if (!slotDate || !/^\d{4}-\d{2}-\d{2}$/.test(slotDate)) {
			return { success: false, error: 'Ungültiges Datum.' };
		}

		// Validate planId is non-empty
		if (!planId) {
			return { success: false, error: 'Fehlende Plan-ID.' };
		}

		// Validate recipeId is UUID-like format
		if (!recipeId || !/^[0-9a-f-]{36}$/.test(recipeId)) {
			return { success: false, error: 'Ungültige Rezept-ID.' };
		}

		const api = apiClient(fetch);
		const { data, error } = await api.POST('/v1/week-plans/{id}/slots', {
			params: { path: { id: planId } },
			body: { slotDate, recipeId }
		});

		if (error || !data) {
			return { success: false, error: 'Gericht konnte nicht hinzugefügt werden.' };
		}

		// Redirect back to the planner after successful pick (spec: "returns to C1")
		redirect(303, `/planner?week=${weekStart || slotDate.slice(0, 7) + '-01'}`);
	}
};