import { apiClient } from '../shared/api-client.js';

export {
    addDays,
    dayName,
    formatDate,
    formatWeekLabel,
    parseIsoDate,
    startOfWeek,
    toIsoDate,
    trimTime,
    weekDates,
    weekEndIso,
    WEEK_LENGTH_DAYS
} from '../shared/dates.js';

export const OVERVIEW_DAYS = 14;
export const GROUP_STORAGE_KEY = 'studentGroupId';

export function groupLessonsByDate(lessons) {
    const byDate = new Map();
    (lessons || []).forEach(lesson => {
        if (!byDate.has(lesson.date)) byDate.set(lesson.date, []);
        byDate.get(lesson.date).push(lesson);
    });
    return byDate;
}

export function buildLessonChips(lesson) {
    const groups = Array.isArray(lesson.groupNames) ? lesson.groupNames.join(', ') : '';
    const subgroups = Array.isArray(lesson.subgroupNames) && lesson.subgroupNames.length
        ? lesson.subgroupNames.join(', ')
        : lesson.subgroupName;
    return [
        lesson.lessonTypeName,
        subgroups,
        lesson.lessonFormat,
        lesson.teacherName,
        lesson.classroomName,
        groups
    ].filter(Boolean);
}

export function buildWeekStatusMessage(lessons) {
    const count = Array.isArray(lessons) ? lessons.length : 0;
    return count > 0 ? `Найдено занятий: ${count}` : 'На этой неделе занятий нет';
}

export function resolveSelectedGroup(groups, savedGroupId = '') {
    if (!Array.isArray(groups) || groups.length === 0) return null;
    return groups.find(group => String(group.id) === String(savedGroupId)) || groups[0];
}

export function groupOptionDescription(group) {
    return [
        group.specialtyCode,
        group.specialtyProfileName,
        group.course ? `${group.course} курс` : ''
    ].filter(Boolean).join(' · ');
}

export async function fetchGroupOptions({ query = '', selectedId = '' } = {}, client = apiClient) {
    const params = new URLSearchParams({ query, limit: '20' });
    if (selectedId) params.set('selectedId', selectedId);
    return client.get(`/api/groups/options?${params}`, { errorMessage: 'Не удалось загрузить группы' });
}

export async function fetchSchedule({ groupId, startDate, endDate }, client = apiClient) {
    return client.get(
        `/api/schedule?groupId=${encodeURIComponent(groupId)}&startDate=${startDate}&endDate=${endDate}`,
        { errorMessage: 'Не удалось загрузить расписание' }
    );
}