/* global jQuery */
/**
 * Sprint settings page: JSON mutation plumbing + jQuery UI sortable wiring.
 *
 * The settings page mounts a single root element with `data-sprint-id` and
 * `data-csrf`. Everything below scopes itself to that root.
 */
(function ($) {
    'use strict';

    const $root = $('[data-sprint-root]');
    if ($root.length === 0) {
        return;
    }

    const sprintId = parseInt($root.data('sprint-id'), 10);
    const csrf     = String($root.data('csrf') || '');

    // ---------------------------------------------------------------------
    // AJAX plumbing
    // ---------------------------------------------------------------------

    function request(method, url, body) {
        const opts = {
            method,
            headers: {
                'Accept':        'application/json',
                'X-CSRF-Token':  csrf,
            },
            credentials: 'same-origin',
        };
        if (body !== undefined) {
            opts.headers['Content-Type'] = 'application/json';
            opts.body = JSON.stringify(body);
        }
        return fetch(url, opts).then(async function (res) {
            let payload = null;
            try { payload = await res.json(); } catch (_) { /* ignore */ }
            if (!res.ok || !payload || payload.ok !== true) {
                const msg = (payload && payload.error && payload.error.message)
                    ? payload.error.message
                    : res.statusText || 'Request failed';
                const err = new Error(msg);
                err.status = res.status;
                err.payload = payload;
                throw err;
            }
            return payload.data;
        });
    }

    // ---------------------------------------------------------------------
    // Toast / status line
    // ---------------------------------------------------------------------

    const $status = $root.find('[data-status]');
    let statusTimer = null;
    function flash(text, isError) {
        $status
            .text(text)
            .removeClass('text-green-700 text-red-700 bg-green-50 bg-red-50 border-green-200 border-red-200')
            .addClass(isError ? 'text-red-700 bg-red-50 border-red-200' : 'text-green-700 bg-green-50 border-green-200')
            .removeClass('opacity-0')
            .addClass('opacity-100');
        clearTimeout(statusTimer);
        statusTimer = setTimeout(function () {
            $status.removeClass('opacity-100').addClass('opacity-0');
        }, 2500);
    }

    // ---------------------------------------------------------------------
    // Sprint meta — save on change / blur
    // ---------------------------------------------------------------------

    function patchMeta(payload) {
        return request('PATCH', '/sprints/' + sprintId, payload)
            .then(function () { flash('Saved'); })
            .catch(function (e) { flash(e.message, true); });
    }

    const metaDebounce = {};
    function debouncedMeta(field, value, ms) {
        clearTimeout(metaDebounce[field]);
        metaDebounce[field] = setTimeout(function () {
            const payload = {};
            payload[field] = value;
            patchMeta(payload);
        }, ms || 400);
    }

    $root.find('[data-meta]').on('change', function () {
        const $el = $(this);
        const field = $el.attr('name');
        let v = $el.val();
        if (field === 'reserve_fraction') {
            v = Number(v) / 100; // form shows percent
        }
        debouncedMeta(field, v, 0);
    });

    // ---------------------------------------------------------------------
    // Weeks count
    // ---------------------------------------------------------------------

    $root.find('[data-weeks-form]').on('submit', function (ev) {
        ev.preventDefault();
        const n = parseInt($(this).find('input[name="n_weeks"]').val(), 10);
        if (!Number.isInteger(n) || n < 1) {
            flash('Weeks must be a positive integer', true);
            return;
        }
        request('POST', '/sprints/' + sprintId + '/weeks', { n_weeks: n })
            .then(function () { window.location.reload(); })
            .catch(function (e) { flash(e.message, true); });
    });

    // ---------------------------------------------------------------------
    // Per-week weekday checkboxes (Phase 12)
    //
    // Each row carries five [data-day-toggle] boxes. On any change we rebuild
    // the row's mask from all five and send it in one PATCH — no debounce on
    // per-checkbox granularity (each click is one state change), but we do
    // delay per-row in case the user ticks several in quick succession.
    // ---------------------------------------------------------------------

    const weekDebounce = {};

    function maskFromRow($row) {
        let mask = 0;
        $row.find('[data-day-toggle]').each(function () {
            if ($(this).is(':checked')) {
                const bit = parseInt($(this).data('bit'), 10);
                if (Number.isInteger(bit)) { mask |= (1 << bit); }
            }
        });
        return mask;
    }

    function popcount5(mask) {
        let n = 0;
        for (let i = 0; i < 5; i++) { if ((mask >> i) & 1) { n++; } }
        return n;
    }

    $root.on('change', '[data-day-toggle]', function () {
        const $row   = $(this).closest('[data-week-row]');
        const weekId = parseInt($row.data('week-id'), 10);
        const mask   = maskFromRow($row);

        // Optimistic local update: derived count flips immediately.
        $row.find('[data-week-count]').text(String(popcount5(mask)));

        clearTimeout(weekDebounce[weekId]);
        weekDebounce[weekId] = setTimeout(function () {
            request('PATCH', '/sprints/' + sprintId + '/week/' + weekId, { active_days_mask: mask })
                .then(function (data) {
                    if (data && data.sprint_week) {
                        $row.find('[data-week-count]')
                            .text(String(data.sprint_week.max_working_days));
                    }
                    flash('Saved');
                })
                .catch(function (e) { flash(e.message, true); });
        }, 250);
    });

    // ---------------------------------------------------------------------
    // Worker picker
    // ---------------------------------------------------------------------

    function workerRowTemplate(sw) {
        const nameSafe = $('<div>').text(sw.worker_name).html();
        return $(
            '<li class="flex items-center gap-2 px-3 py-2 border-b bg-white last:border-b-0"' +
               ' data-sw-id="' + sw.id + '"' +
               ' data-worker-id="' + sw.worker_id + '">' +
                '<span class="handle cursor-grab text-slate-400">&#8801;</span>' +
                '<span class="flex-1">' + nameSafe + '</span>' +
                '<input type="number" step="0.05" min="0" max="1" value="' + Number(sw.rtb).toFixed(2) + '"' +
                    ' data-rtb class="w-20 rounded border border-slate-300 px-2 py-1 font-mono text-sm focus:outline-none focus:ring-2 focus:ring-slate-400">' +
                '<button type="button" data-remove class="text-sm text-red-600 hover:underline">Remove</button>' +
            '</li>'
        );
    }

    function availableRowTemplate(worker) {
        const nameSafe = $('<div>').text(worker.name).html();
        return $(
            '<li class="flex items-center gap-2 px-3 py-2 border-b last:border-b-0"' +
               ' data-worker-id="' + worker.id + '">' +
                '<span class="flex-1">' + nameSafe + '</span>' +
                '<button type="button" data-add class="text-sm text-blue-700 hover:underline">Add →</button>' +
            '</li>'
        );
    }

    const $available = $root.find('[data-available]');
    const $inSprint  = $root.find('[data-in-sprint]');

    // Add a worker
    $available.on('click', '[data-add]', function () {
        const $li = $(this).closest('li');
        const workerId = parseInt($li.data('worker-id'), 10);
        const name = $li.find('span.flex-1').text();

        request('POST', '/sprints/' + sprintId + '/workers', { worker_id: workerId })
            .then(function (data) {
                const sw = data.sprint_worker;
                sw.worker_name = sw.worker_name || name;
                $inSprint.append(workerRowTemplate(sw));
                $li.remove();
                flash('Worker added');
                refreshEmptyStates();
            })
            .catch(function (e) { flash(e.message, true); });
    });

    // Remove a worker
    $inSprint.on('click', '[data-remove]', function () {
        const $li = $(this).closest('li');
        const swId = parseInt($li.data('sw-id'), 10);
        const workerId = parseInt($li.data('worker-id'), 10);
        const name = $li.find('span.flex-1').text();

        request('DELETE', '/sprints/' + sprintId + '/workers/' + swId)
            .then(function () {
                $li.remove();
                $available.append(availableRowTemplate({ id: workerId, name: name }));
                flash('Worker removed');
                refreshEmptyStates();
            })
            .catch(function (e) { flash(e.message, true); });
    });

    // RTB edit on blur / change
    $inSprint.on('change', '[data-rtb]', function () {
        const $input = $(this);
        const swId = parseInt($input.closest('li').data('sw-id'), 10);
        let v = Number($input.val());
        if (Number.isNaN(v) || v < 0 || v > 1) {
            flash('RTB must be 0–1', true);
            return;
        }
        // Snap to 0.05 step
        v = Math.round(v * 20) / 20;
        $input.val(v.toFixed(2));

        request('PATCH', '/sprints/' + sprintId + '/workers/' + swId, { rtb: v })
            .then(function () { flash('Saved'); })
            .catch(function (e) { flash(e.message, true); });
    });

    // Drag reorder (requires jQuery UI)
    if (typeof $.fn.sortable === 'function') {
        $inSprint.sortable({
            handle: '.handle',
            axis: 'y',
            placeholder: 'bg-slate-100 h-10',
            update: function () {
                const ordering = $inSprint.children('li').map(function (i, el) {
                    return {
                        sprint_worker_id: parseInt($(el).data('sw-id'), 10),
                        sort_order: i + 1,
                    };
                }).get();

                request('POST', '/sprints/' + sprintId + '/workers/reorder', ordering)
                    .then(function (data) {
                        flash(data.moved ? 'Order saved' : 'No changes');
                    })
                    .catch(function (e) { flash(e.message, true); });
            },
        });
    } else {
        // eslint-disable-next-line no-console
        console.warn('[sprint-settings] jQuery UI not loaded — drag reorder disabled.');
    }

    function refreshEmptyStates() {
        $root.find('[data-empty-available]').toggle($available.children('li').length === 0);
        $root.find('[data-empty-sprint]').toggle($inSprint.children('li').length === 0);
    }
    refreshEmptyStates();

})(jQuery);