// MARK: - Imports
// #region Imports
import fs from 'fs';
import { cleanValue } from './csvParser.js';
import { computeSkeleHash } from './imageHasher.js';
import { createLogger } from '../../util/logger.js';
// #endregion

const log = createLogger('import');

// MARK: - Category Importer
// #region Category Importer

/**
 * Imports category tree and attaches category images.
 *
 * @param {object} params
 * @param {object} params.store - Store singleton
 * @param {number} params.googleAuthId
 * @param {Array<Record<string, string>>} params.includedCategories
 * @param {Array<object>} params.categoryImageTasks
 * @param {object} params.progressTracker
 * @returns {Promise<{ jtlCatIdToDashCatId: Map<string, number>, hauptDashId: number, createdCatCount: number, catPicCount: number }>}
 */
export async function importCategories({
    store,
    googleAuthId,
    includedCategories,
    categoryImageTasks,
    progressTracker,
}) {
    const treeResult = await store.category.getTreeForCompany(googleAuthId);
    const existingTree = treeResult.tree || [];
    const rootCategory = existingTree.find((c) => c.parentId == null) || existingTree[0];
    if (!rootCategory) {
        throw new Error('Company root category not found');
    }
    const rootCategoryId = rootCategory.id;

    const existingMap = new Map();
    for (const c of existingTree) {
        const key = `${c.parentId ?? 'root'}:${String(c.name || '').trim().toLowerCase()}`;
        existingMap.set(key, c.id);
    }

    const jtlCatIdToDashCatId = new Map();
    jtlCatIdToDashCatId.set('0', rootCategoryId);

    // Group category images by JTL category ID
    const catImagesByJtlId = new Map();
    for (const task of categoryImageTasks) {
        if (!catImagesByJtlId.has(task.catJtlId)) {
            catImagesByJtlId.set(task.catJtlId, []);
        }
        catImagesByJtlId.get(task.catJtlId).push(task);
    }

    function parseSortValue(val) {
        if (val == null || val === '') return 0;
        const n = Number(val);
        return Number.isFinite(n) ? n : 0;
    }

    const pendingCats = includedCategories.map((c, idx) => ({ ...c, _csvIndex: idx }));
    let createdCatCount = 0;
    let catPicCount = 0;
    let safety = 0;

    const importedMetaByCatId = new Map();
    const touchedParentIds = new Set();

    while (pendingCats.length > 0 && safety < 10) {
        safety++;
        const readyCats = [];
        const remaining = [];

        for (const c of pendingCats) {
            const jtlParent = String(c.parentid ?? c.kOberKategorie ?? '0');
            if (jtlParent === '0' || !jtlParent || jtlCatIdToDashCatId.has(jtlParent)) {
                readyCats.push(c);
            } else {
                remaining.push(c);
            }
        }

        // Group by parent and order siblings numerically by CSV sort column, maintaining CSV order on ties
        readyCats.sort((a, b) => {
            const parentA = String(a.parentid ?? a.kOberKategorie ?? '0');
            const parentB = String(b.parentid ?? b.kOberKategorie ?? '0');
            if (parentA !== parentB) {
                return parentA.localeCompare(parentB);
            }
            const sortA = parseSortValue(a.sort ?? a.nSort);
            const sortB = parseSortValue(b.sort ?? b.nSort);
            if (sortA !== sortB) return sortA - sortB;
            return a._csvIndex - b._csvIndex;
        });

        for (const c of readyCats) {
            const jtlId = String(c.id ?? c.kKategorie);
            const jtlParent = String(c.parentid ?? c.kOberKategorie ?? '0');

            let name = cleanValue(c.name ?? c.cName);
            if (!name) {
                try {
                    const tr = JSON.parse(c.translations || '[]');
                    name = tr[0]?.name || tr[0]?.cName || '';
                } catch {}
            }
            if (!name) name = `Kategorie ${jtlId}`;

            let dashParentId;
            if (jtlParent === '0' || !jtlParent) {
                dashParentId = rootCategoryId;
            } else if (jtlCatIdToDashCatId.has(jtlParent)) {
                dashParentId = jtlCatIdToDashCatId.get(jtlParent);
            } else {
                remaining.push(c);
                continue;
            }

            const key = `${dashParentId}:${name.toLowerCase()}`;
            let dashCatId = existingMap.get(key);

            if (!dashCatId) {
                try {
                    const created = await store.category.createUnderParent({
                        googleAuthId,
                        parentId: dashParentId,
                        name,
                    });
                    dashCatId = created.id;
                    existingMap.set(key, dashCatId);
                    createdCatCount++;
                } catch (err) {
                    log.warn(`Failed to create category "${name}":`, err.message);
                }
            }

            if (dashCatId) {
                jtlCatIdToDashCatId.set(jtlId, dashCatId);
                importedMetaByCatId.set(dashCatId, {
                    sort: parseSortValue(c.sort ?? c.nSort),
                    csvIndex: c._csvIndex,
                });
                touchedParentIds.add(dashParentId);

                // Add category images
                const imgs = catImagesByJtlId.get(jtlId) || [];
                for (const imgTask of imgs) {
                    try {
                        const imgBuf = fs.readFileSync(imgTask.fullPath);
                        await store.category.addImage(googleAuthId, dashCatId, imgBuf);
                        catPicCount++;

                        const skele = await computeSkeleHash(imgBuf);
                        progressTracker.emitSkeleHash(skele?.base62 || null);
                    } catch (err) {
                        log.warn(`Category image error (${imgTask.relPath}):`, err.message);
                    }
                    progressTracker.counts.imagesdone++;
                }
            }

            progressTracker.counts.categoriesdone++;
            progressTracker.emitProgress();
        }
        pendingCats.length = 0;
        pendingCats.push(...remaining);
    }

    // Explicit sibling reordering pass using store.category.order
    if (touchedParentIds.size > 0 && typeof store.category?.order === 'function') {
        try {
            const treeAfter = await store.category.getTreeForCompany(googleAuthId);
            const allNodes = treeAfter.tree || [];

            for (const parentId of touchedParentIds) {
                const siblings = allNodes.filter((node) => node.parentId === parentId);
                if (siblings.length <= 1) continue;

                siblings.sort((a, b) => {
                    const metaA = importedMetaByCatId.get(a.id);
                    const metaB = importedMetaByCatId.get(b.id);
                    const sortA = metaA ? metaA.sort : Infinity;
                    const sortB = metaB ? metaB.sort : Infinity;
                    if (sortA !== sortB) return sortA - sortB;
                    const idxA = metaA ? metaA.csvIndex : (a.sort ?? 0);
                    const idxB = metaB ? metaB.csvIndex : (b.sort ?? 0);
                    return idxA - idxB;
                });

                const categoryIds = siblings.map((s) => s.id);
                try {
                    await store.category.order({
                        googleAuthId,
                        parentId,
                        categoryIds,
                    });
                } catch (orderErr) {
                    log.warn(`Failed to apply category order for parent ${parentId}:`, orderErr.message);
                }
            }
        } catch (err) {
            log.warn('Failed to fetch tree for category reordering:', err.message);
        }
    }

    progressTracker.flushSkeleHashes();
    progressTracker.emitProgress(true);
    log.info(`Categories resolved: ${jtlCatIdToDashCatId.size}/${includedCategories.length}, created: ${createdCatCount}, images: ${catPicCount}`);

    const hauptDashId = jtlCatIdToDashCatId.get('1') || rootCategoryId;

    return {
        jtlCatIdToDashCatId,
        hauptDashId,
        createdCatCount,
        catPicCount,
    };
}

// #endregion