/**
 * VDA 4913 → DELVRY03 (XML-IDoc) Converter
 * Based on: ifm electronic EDI Guide XML-DELVRY03 v1.0 (30.06.2020)
 * Input:  Parsed VDA 4913 object from VDAParser (vda-parser.js)
 * Output: EDIFACT-style IDoc field map object ready for XML serialisation
 *         OR a flat key=value string for direct IDoc inbound processing.
 *
 * Segment mapping:
 *   VDA 711 → EDI_DC40 + E1EDL20 (delivery header)
 *   VDA 712 → E1EDL20 transport fields (carrier, weight)
 *   VDA 713 → E1EDL20 delivery note fields + E1ADRM1 (ship-to)
 *   VDA 714 → E1EDL24 (delivery item)
 *   VDA 715 → E1EDL37 (handling unit)
 */
window.EDIBridge = window.EDIBridge || {};

class VDA4913ToDELVRY03 {

    // ── Unit mapping VDA → SAP/IDoc ──────────────────────────────────────────
    static UNIT_MAP = {
        'ST':  'PCE',
        'PCE': 'PCE',
        'KG':  'KG',
        'KGM': 'KG',
        'L':   'L',
        'MTR': 'M',
        'M':   'M',
        'PAL': 'PAL',
        'CTN': 'CTN',
    };

    // ── Transport type mapping VDA → SAP TRAGY ────────────────────────────────
    static TRANSPORT_MAP = {
        '1': '01', // Sea
        '2': '02', // Rail
        '3': '03', // Road
        '4': '04', // Air
        '5': '05', // Post
    };

    // ─────────────────────────────────────────────────────────────────────────
    // Main entry point
    // @param {object} parsed  – result of VDAParser.parse()
    // @param {object} config  – { senderId, receiverId, plant, salesOrg, ... }
    // @returns {object}       – IDoc structure { control: {}, segments: [] }
    // ─────────────────────────────────────────────────────────────────────────
    static convert(parsed, config = {}) {
        const idocs = [];

        for (const interchange of (parsed.interchanges || [])) {
            const hdr711 = interchange.header || {};

            for (const transport of (interchange.transports || [])) {
                const hdr712 = transport.data || {};

                for (const dn of (transport.deliveryNotes || [])) {
                    const hdr713 = dn.header || {};
                    idocs.push(this._buildIDoc(hdr711, hdr712, hdr713, dn, config));
                }
            }
        }

        return idocs;
    }

    // ─────────────────────────────────────────────────────────────────────────
    // Build one IDoc per delivery note
    // ─────────────────────────────────────────────────────────────────────────
    static _buildIDoc(hdr711, hdr712, hdr713, dn, config) {
        const now    = new Date();
        const dateNow = this._fmtDate(now);
        const timeNow = this._fmtTime(now);

        const senderId   = config.senderId   || hdr711.sourceId || 'SUPPLIER';
        const receiverId = config.receiverId || hdr711.targetId || 'IFM';
        const docNum     = hdr713.dnNo       || hdr712.refNo    || '';
        const delivDate  = this._vdaDate(hdr713.date || hdr712.date || dateNow);

        // ── EDI_DC40 – Control Record ─────────────────────────────────────────
        const control = {
            TABNAM:   'EDI_DC40',
            MANDT:    config.client    || '600',
            DOCNUM:   docNum.padStart(16, '0'),
            DOCREL:   config.docrel    || '750',
            STATUS:   '30',
            DIRECT:   '1',
            OUTMOD:   '2',
            IDOCTYP:  'DELVRY03',
            MESTYP:   'STPOD',
            STD:      'E',
            STDVRS:   '003',
            STDMES:   'DELVRY',
            SNDPOR:   config.sndPort   || 'EDIPORT',
            SNDPRT:   'LS',
            SNDPRN:   senderId.substring(0, 10),
            SNDLAD:   senderId.substring(0, 21),
            RCVPOR:   config.rcvPort   || 'SAPPORT',
            RCVPRT:   'LI',
            RCVPRN:   receiverId.substring(0, 10),
            RCVLAD:   '1000280',
            CREDAT:   dateNow,
            CRETIM:   timeNow,
        };

        const segments = [];

        // ── E1EDL20 – Delivery Header ─────────────────────────────────────────
        // VDA 712: carrier (16-30), date (30-36), time (36-40)
        // VDA 713: dnNo (5-13), date (13-19), unloadingPoint (19-24)
        const e1edl20 = {
            _SEGMENT: 'E1EDL20',
            VBELN:    docNum.padStart(10, '0'),          // Delivery note number
            VSTEL:    hdr713.unloadingPoint || config.shippingPoint || '',  // Shipping point
            VKORG:    config.salesOrg       || '',
            LGNUM:    config.warehouseNo    || '',
            ABLAD:    hdr713.unloadingPoint || '',       // Unloading point
            BTGEW:    String(hdr712.grossWeight || ''), // Total weight
            NTGEW:    String(hdr712.netWeight   || ''), // Net weight
            GEWEI:    'KG',
            BOLNR:    hdr712.refNo          || '',       // Bill of lading
            TRATY:    this.TRANSPORT_MAP[hdr712.transportType] || '',
            TRAID:    hdr712.carrierName    || '',       // Carrier name / transport ID
            LIFEX:    docNum,                            // External delivery note no.
            PARID:    senderId,                          // External partner number
            PODAT:    this._vdaDate(hdr713.date || hdr712.date || ''), // Proof of delivery date
            POTIM:    hdr712.time           || '',
        };
        segments.push(e1edl20);

        // ── E1ADRM1 – Ship-To Address (partner function WE) ───────────────────
        // From VDA 713: qualifier (24-30), orderNo (30-38)
        const e1adrm1 = {
            _SEGMENT: 'E1ADRM1',
            PARTNER_Q:  'WE',
            ADDRESS_T:  '1',
            PARTNER_ID: config.shipToId || hdr713.qualifier || '',
            NAME1:      config.shipToName || 'ifm electronic gmbh',
            STREET1:    config.shipToStreet || '',
            CITY1:      config.shipToCity   || '',
            POSTL_COD1: config.shipToZip   || '',
            COUNTRY1:   config.shipToCountry || 'DE',
        };
        segments.push(e1adrm1);

        // ── E1ADRM1 – Supplier Address (partner function LF) ─────────────────
        const e1adrm1_lf = {
            _SEGMENT: 'E1ADRM1',
            PARTNER_Q:  'LF',
            ADDRESS_T:  '1',
            PARTNER_ID: senderId,
            NAME1:      config.supplierName   || '',
            STREET1:    config.supplierStreet || '',
            CITY1:      config.supplierCity   || '',
            POSTL_COD1: config.supplierZip    || '',
            COUNTRY1:   config.supplierCountry || 'DE',
        };
        segments.push(e1adrm1_lf);

        // ── E1EDL24 – Delivery Items ──────────────────────────────────────────
        // VDA 714: custMat (5-27), suppMat (27-49), qty (53-65)/1000, unit (65-67), refNo (77-90)
        let posNr = 10;
        for (const pos of (dn.positions || [])) {
            const d = pos.data || {};
            const unit = this.UNIT_MAP[d.unit] || d.unit || 'PCE';

            const e1edl24 = {
                _SEGMENT: 'E1EDL24',
                POSNR:    String(posNr).padStart(6, '0'),
                MATNR:    d.suppMat  || '',              // Supplier material number
                MATWA:    d.suppMat  || '',              // Material entered
                ARKTX:    '',                            // Short text
                KDMAT:    d.custMat  || '',              // Customer material number
                LGMNG:    String(d.qty || 0),            // Actual delivery qty
                VRKME:    unit,                          // Sales unit
                MEINS:    unit,                          // Base unit
                VGBEL:    hdr713.orderNo || '',          // Reference document (order)
                VGPOS:    String(posNr).padStart(6, '0'),
                WERKS:    config.plant || '1110',        // Plant
            };
            segments.push(e1edl24);

            // ── E1EDL37 – Handling Units (from VDA 715 packaging lines) ───────
            // VDA 715: packMatCust (5-27), packMatSupp (27-49), qty (59-62),
            //          labelFrom (78-87), labelTo (87-96)
            let huCounter = 1;
            for (const pack of (pos.packaging || [])) {
                const huId = String(huCounter).padStart(10, '0');
                const e1edl37 = {
                    _SEGMENT: 'E1EDL37',
                    VPOSNR:   String(posNr).padStart(6, '0'),
                    VEGR1:    pack.packMatSupp || pack.packMatCust || '', // HU type
                    ANZPK:    String(pack.qty || 1),                      // Number of packages
                    EXIDV:    pack.labelFrom  || huId,                    // External HU ID (label from)
                    EXIDV2:   pack.labelTo    || '',                      // Label to
                };
                segments.push(e1edl37);
                huCounter++;
            }

            // ── E1EDL14 – DG Control Data (delivery item) – only if needed ───
            // Skipped unless config.includeDG = true

            posNr += 10;
        }

        // ── Free texts from VDA 716 ───────────────────────────────────────────
        if (dn.texts && dn.texts.length > 0) {
            const e1txth8 = {
                _SEGMENT: 'E1TXTH8',
                FUNCTION: 'H',
                TDOBJECT: 'VBBK',
                TDOBNAME: docNum,
                TDID:     '0001',
                TDSPRAS:  '1',
                TDTEXTTYPE: 'GRKO',
                LANGUA_ISO: 'DE',
            };
            segments.push(e1txth8);

            for (const txt of dn.texts) {
                segments.push({
                    _SEGMENT: 'E1TXTP8',
                    TDFORMAT: '*',
                    TDLINE:   txt.substring(0, 132),
                });
            }
        }

        return { control, segments };
    }

    // ─────────────────────────────────────────────────────────────────────────
    // Serialise IDoc array to flat IDoc text format (for file-based inbound)
    // ─────────────────────────────────────────────────────────────────────────
    static toIdocText(idocs) {
        const lines = [];
        let docNum = 1;

        for (const idoc of idocs) {
            const dn = String(docNum++).padStart(16, '0');

            // Control record
            const ctrl = { ...idoc.control, DOCNUM: dn };
            lines.push(this._flatRecord('EDI_DC40', ctrl));

            // Data segments
            let segNum = 1;
            for (const seg of idoc.segments) {
                const segName = seg._SEGMENT;
                const fields  = { ...seg };
                delete fields._SEGMENT;
                lines.push(this._flatRecord(segName, fields, dn, segNum++));
            }
        }

        return lines.join('\n');
    }

    // ─────────────────────────────────────────────────────────────────────────
    // Serialise to structured JSON (for XML generation or further processing)
    // ─────────────────────────────────────────────────────────────────────────
    static toJSON(idocs) {
        return JSON.stringify(idocs, null, 2);
    }

    // ─────────────────────────────────────────────────────────────────────────
    // Serialise to XML-IDoc format (as expected by ifm DELVRY03 guide)
    // ─────────────────────────────────────────────────────────────────────────
    static toXML(idocs) {
        const xmlParts = ['<?xml version="1.0" encoding="UTF-8"?>', '<DELVRY03>'];

        for (const idoc of idocs) {
            xmlParts.push('  <IDOC BEGIN="1">');

            // Control record
            xmlParts.push('    <EDI_DC40 SEGMENT="1">');
            for (const [k, v] of Object.entries(idoc.control)) {
                if (v !== undefined && v !== '') {
                    xmlParts.push(`      <${k}>${this._xmlEsc(v)}</${k}>`);
                }
            }
            xmlParts.push('    </EDI_DC40>');

            // Data segments
            for (const seg of idoc.segments) {
                const name = seg._SEGMENT;
                xmlParts.push(`    <${name} SEGMENT="1">`);
                for (const [k, v] of Object.entries(seg)) {
                    if (k === '_SEGMENT') continue;
                    if (v !== undefined && v !== '') {
                        xmlParts.push(`      <${k}>${this._xmlEsc(v)}</${k}>`);
                    }
                }
                xmlParts.push(`    </${name}>`);
            }

            xmlParts.push('  </IDOC>');
        }

        xmlParts.push('</DELVRY03>');
        return xmlParts.join('\n');
    }

    // ─────────────────────────────────────────────────────────────────────────
    // Helpers
    // ─────────────────────────────────────────────────────────────────────────

    /** VDA date YYMMDD → YYYYMMDD */
    static _vdaDate(d) {
        if (!d) return '';
        d = String(d).replace(/\D/g, '');
        if (d.length === 6) return '20' + d;   // YYMMDD → YYYYMMDD
        if (d.length === 8) return d;           // already YYYYMMDD
        return d;
    }

    /** Date object → YYYYMMDD */
    static _fmtDate(dt) {
        return dt.toISOString().replace(/-/g, '').substring(0, 8);
    }

    /** Date object → HHMMSS */
    static _fmtTime(dt) {
        return dt.toISOString().replace(/:/g, '').substring(11, 17);
    }

    /** Flat IDoc record line */
    static _flatRecord(segName, fields, docNum = '', segNum = 0) {
        const parts = [segName.padEnd(30)];
        if (docNum) parts.push(docNum.padStart(16, '0'));
        if (segNum) parts.push(String(segNum).padStart(6, '0'));
        for (const [k, v] of Object.entries(fields)) {
            parts.push(`${k}=${v}`);
        }
        return parts.join(' ');
    }

    /** XML escape */
    static _xmlEsc(v) {
        return String(v)
            .replace(/&/g, '&amp;')
            .replace(/</g, '&lt;')
            .replace(/>/g, '&gt;')
            .replace(/"/g, '&quot;');
    }
}

window.EDIBridge.VDA4913ToDELVRY03 = VDA4913ToDELVRY03;