/**
 * Hoover — components/modal.js
 *
 * Modal overlay system: openModal, closeModal, closeAllModals, formModal.
 * Renders directly into #modal-root using DOM manipulation (not vdom) to
 * avoid fighting with the main render cycle.
 */

import { esc } from '../helpers.js?v=6';
import { att_esc } from '../helpers.js?v=6';
import { apiSubmit } from '../api.js?v=6';

const _modalQueue = [];

function _renderModals() {
    const root = document.getElementById('modal-root');
    if (!root) return;
    root.innerHTML = '';
    _modalQueue.forEach((m, idx) => {
        const wrap = document.createElement('div');
        wrap.className = 'modal-overlay active';
        wrap.onclick = (e) => { if (e.target === wrap) closeModal(idx); };
        const content = document.createElement('div');
        content.className = 'modal';
        content.onclick = (e) => e.stopPropagation();
        if (m.renderFn) {
            try { m.renderFn(content, idx); }
            catch (err) { content.textContent = err.message; }
        }
        wrap.appendChild(content);
        root.appendChild(wrap);
    });
}

/**
 * Open a modal dialog.
 *
 * @param {function} renderFn – (contentEl, idx) => void, renders into contentEl
 */
export function openModal(renderFn) {
    _modalQueue.push({ renderFn, id: _modalQueue.length });
    _renderModals();
}

/**
 * Close a modal by index. Closes the topmost modal if index is omitted.
 *
 * @param {number} [idx]
 */
export function closeModal(idx) {
    if (idx === undefined) idx = _modalQueue.length - 1;
    if (idx >= 0 && idx < _modalQueue.length) _modalQueue.splice(idx, 1);
    _renderModals();
}

/**
 * Close all open modals.
 */
export function closeAllModals() {
    _modalQueue.length = 0;
    _renderModals();
}

/**
 * Render a standard modal layout: title, form fields, action buttons.
 *
 * @param {HTMLElement} inner     – Modal content element to fill
 * @param {string}      title     – Modal title
 * @param {object[]}    fields    – Form field descriptors
 * @param {object[]}    actions   – Action button descriptors
 *
 * Field shape:
 *   { label, id, [tag: 'input'|'select'|'textarea'], [type], [value], [placeholder], [options] }
 *
 * Action shape:
 *   { label, cls, action, handler }
 */
export function formModal(inner, title, fields, actions) {
    inner.innerHTML = '<h2 class="modal-title">' + esc(title) + '</h2><div class="modal-body">'
        + fields.map(f => {
            if (f.tag === 'select')
                return '<div class="form-group"><label>' + esc(f.label) + '</label><select id="' + att_esc(f.id) + '"'
                    + (f.multiple ? ' multiple' : '') + '>'
                    + (f.options || []).map(o =>
                        typeof o === 'string'
                            ? '<option value="' + att_esc(o) + '">' + esc(o) + '</option>'
                            : '<option value="' + att_esc(o[0]) + '"' + (o[1] ? ' selected' : '') + '>' + esc(o[1]) + '</option>',
                    ).join('') + '</select></div>';

            const tag = f.tag || 'input';
            return '<div class="form-group"><label>' + esc(f.label) + '</label><' + tag + ' id="' + att_esc(f.id) + '"'
                + (f.type !== 'text' ? ' type="' + att_esc(f.type) + '"' : '')
                + (f.value !== undefined ? ' value="' + att_esc(f.value) + '"' : '')
                + (f.placeholder ? ' placeholder="' + att_esc(f.placeholder) + '"' : '')
                + '></' + tag + '></div>';
        }).join('') + '</div><div class="modal-actions">'
        + actions.map(a =>
            '<button class="btn ' + att_esc(a.cls) + '" data-action="' + att_esc(a.action) + '">' + esc(a.label) + '</button>',
        ).join('') + '</div>';

    actions.forEach(a => {
        const btn = inner.querySelector('[data-action="' + att_esc(a.action) + '"]');
        if (btn) btn.addEventListener('click', a.handler);
    });
}

/**
 * Factory that returns a function to open a multi-select modal.
 *
 * @param {object} props
 * @param {string} props.title       - Modal title
 * @param {string} props.url         - API POST URL
 * @param {string[]} props.options   - All selectable options
 * @param {string[]} props.selected  - Currently selected values
 * @param {string} props.fieldKey    - JSON key for the field
 * @param {string} [props.successMsg] - Success toast message
 * @param {function} [props.reload]  - () => Promise, called on success
 * @returns {function} () => void, calls openModal
 */
export function MultiSelectModal(props = {}) {
    return () => {
        const selectId = 'ms-' + props.fieldKey;
        openModal((inner) => {
            formModal(inner, props.title,
                [{
                    label: props.fieldKey,
                    id: selectId,
                    tag: 'select',
                    multiple: true,
                    options: (props.options || []).map(o => [o, (props.selected || []).includes(o)]),
                }],
                [
                    { label: 'Cancel', cls: 'btn-outline', action: 'c', handler: () => closeModal() },
                    ...apiSubmit({
                        url: props.url,
                        body: () => ({
                            [props.fieldKey]: Array.from(document.getElementById(selectId).selectedOptions)
                                .map(o => o.value),
                        }),
                        successMsg: props.successMsg || 'Updated',
                        reload: props.reload,
                        closeModal: () => closeModal(),
                    }),
                ],
            );
        });
    };
}

/**
 * Factory that returns a function to open a modal with form fields and apiSubmit.
 * Accepts an optional `data` argument forwarded to title, fields, submit.url, submit.body resolvers.
 *
 * @param {object} props
 * @param {string|function} props.title       - Modal title or (data) => string
 * @param {object[]|function} props.fields     - Form field descriptors or (data) => object[]
 * @param {object} props.submit                - Submit configuration
 * @param {string|function} props.submit.url   - API URL or (data) => string
 * @param {string} [props.submit.method]       - HTTP method (default: 'POST')
 * @param {function} [props.submit.body]       - (data) => object
 * @param {function} [props.submit.validate]   - (body) => string|null
 * @param {string|function} [props.submit.successMsg] - Toast message or (data) => string
 * @param {function} [props.reload]            - (data) => Promise, called on success with the data argument
 * @param {function} [props.handler]           - Custom submit handler override (bypasses apiSubmit)
 * @param {string} [props.submitLabel]         - Submit button label (default: 'Submit')
 * @returns {function} (data) => void, calls openModal
 */
export function QuickModal(props = {}) {
    return (data) => {
        const title = typeof props.title === 'function' ? props.title(data) : props.title;
        const fields = typeof props.fields === 'function' ? props.fields(data) : props.fields;
        const url = typeof props.submit.url === 'function' ? props.submit.url(data) : props.submit.url;

        openModal((inner) => {
            let actions;
            if (props.handler) {
                actions = [
                    { label: 'Cancel', cls: 'btn-outline', action: 'c', handler: () => closeModal() },
                    {
                        label: props.submitLabel || 'Submit',
                        cls: 'btn-primary',
                        action: 's',
                        handler: () => props.handler(data, () => closeModal()),
                    },
                ];
            } else {
                actions = [
                    { label: 'Cancel', cls: 'btn-outline', action: 'c', handler: () => closeModal() },
                    ...apiSubmit({
                        url,
                        method: props.submit.method || 'POST',
                        body: props.submit.body ? () => props.submit.body(data) : undefined,
                        validate: props.submit.validate,
                        successMsg: typeof props.submit.successMsg === 'function'
                            ? props.submit.successMsg(data)
                            : (props.submit.successMsg || 'Done'),
                        reload: props.reload ? () => props.reload(data) : undefined,
                        closeModal: () => closeModal(),
                    }),
                ];
            }
            formModal(inner, title, fields, actions);
        });
    };
}