/** @odoo-module **/

/**
 * ESC/POS Command Generator
 *
 * Generates ESC/POS command sequences for thermal printers.
 * Supports text formatting, alignment, sizing, and receipt generation.
 *
 * Column width: 32 chars (58 mm paper) — standard for small Bluetooth thermal printers.
 */

// ESC/POS Command Constants
const ESC = 0x1B;
const GS  = 0x1D;
const LF  = 0x0A;

// Initialization
const INIT = [ESC, 0x40];

// Alignment commands
const ALIGN_LEFT   = [ESC, 0x61, 0x00];
const ALIGN_CENTER = [ESC, 0x61, 0x01];
const ALIGN_RIGHT  = [ESC, 0x61, 0x02];

// Text emphasis
const BOLD_ON      = [ESC, 0x45, 0x01];
const BOLD_OFF     = [ESC, 0x45, 0x00];
const UNDERLINE_ON = [ESC, 0x2D, 0x01];
const UNDERLINE_OFF= [ESC, 0x2D, 0x00];

// Paper control
const FEED_LINE = [LF];
const CUT_PAPER = [GS, 0x56, 0x00];

export class EscPosGenerator {
    constructor() {
        this.commands    = [];
        this.characterSet = 'CP437'; // Default character set
        this.colWidth    = 32;       // 58 mm paper = 32 chars @ 12 cpi
    }

    // ─── Low-level ESC/POS helpers ──────────────────────────────────────────

    initialize() { return new Uint8Array(INIT); }

    setAlignment(alignment) {
        switch ((alignment || '').toLowerCase()) {
            case 'center': return new Uint8Array(ALIGN_CENTER);
            case 'right':  return new Uint8Array(ALIGN_RIGHT);
            default:       return new Uint8Array(ALIGN_LEFT);
        }
    }

    setTextSize(width = 1, height = 1) {
        width  = Math.max(1, Math.min(8, width));
        height = Math.max(1, Math.min(8, height));
        const sizeValue = ((width - 1) << 4) | (height - 1);
        return new Uint8Array([GS, 0x21, sizeValue]);
    }

    setEmphasis(bold = false, underline = false) {
        const cmds = [];
        cmds.push(...(bold      ? BOLD_ON      : BOLD_OFF));
        cmds.push(...(underline ? UNDERLINE_ON : UNDERLINE_OFF));
        return new Uint8Array(cmds);
    }

    feedAndCut(lines = 3) {
        const cmds = [];
        for (let i = 0; i < lines; i++) cmds.push(...FEED_LINE);
        cmds.push(...CUT_PAPER);
        cmds.push(...INIT); // Force printer buffer flush and reset
        return new Uint8Array(cmds);
    }

    /**
     * Encode text to bytes using the configured character set.
     */
    encodeText(text) {
        if (!text) return new Uint8Array(0);

        const result  = new Uint8Array(text.length);
        const charSet = (this.characterSet || 'CP437').toUpperCase();

        const cp437Map = {
            'ü':0x81,'é':0x82,'â':0x83,'ä':0x84,'à':0x85,'å':0x86,'ç':0x87,'ê':0x88,
            'ë':0x89,'è':0x8A,'ï':0x8B,'î':0x8C,'ì':0x8D,'Ä':0x8E,'Å':0x8F,'É':0x90,
            'æ':0x91,'Æ':0x92,'ô':0x93,'ö':0x94,'ò':0x95,'û':0x96,'ù':0x97,'ÿ':0x98,
            'Ö':0x99,'Ü':0x9A,'¢':0x9B,'£':0x9C,'¥':0x9D,'á':0xA0,'í':0xA1,'ó':0xA2,
            'ú':0xA3,'ñ':0xA4,'Ñ':0xA5,'ß':0xE1,'µ':0xE6,'±':0xF1,'°':0xF8,'€':0xEE,
        };
        const cp850Map = {
            ...cp437Map, 'ø':0x9B,'Ø':0x9D,'×':0x9E,'®':0xA9,'€':0xD5,
        };

        const activeMap = (charSet === 'CP850' || charSet === 'CP858' || charSet === 'CP852')
            ? cp850Map : cp437Map;

        for (let i = 0; i < text.length; i++) {
            const ch   = text[i];
            const code = ch.charCodeAt(0);
            if (code <= 127) {
                result[i] = code;
            } else if (activeMap[ch] !== undefined) {
                result[i] = activeMap[ch];
            } else {
                const norm = ch.normalize('NFD').replace(/[\u0300-\u036f]/g, '');
                result[i]  = (norm.length > 0 && norm.charCodeAt(0) <= 127)
                    ? norm.charCodeAt(0) : 0x3F; // '?'
            }
        }
        return result;
    }

    /**
     * Emit a single line of text (with optional formatting) followed by LF.
     */
    addLine(text, options = {}) {
        const cmds = [];
        if (options.align)                                 cmds.push(...this.setAlignment(options.align));
        if (options.width || options.height)               cmds.push(...this.setTextSize(options.width || 1, options.height || 1));
        if (options.bold !== undefined || options.underline !== undefined)
            cmds.push(...this.setEmphasis(options.bold || false, options.underline || false));

        cmds.push(...this.encodeText(text));
        cmds.push(...FEED_LINE);

        // Reset formatting after every line
        cmds.push(...this.setTextSize(1, 1));
        cmds.push(...this.setEmphasis(false, false));
        return new Uint8Array(cmds);
    }

    // ─── Number formatting ───────────────────────────────────────────────────

    /**
     * Format a raw number for thermal receipt printing.
     *
     * Rules:
     *   - Use thousands separators (dot for ID locale style)
     *   - Strip trailing ".00" — currencies like IDR have 0 decimal places
     *     and a value like 29970000.00 should print as "29.970.000"
     *   - Keep up to 2 decimal places if non-zero
     *
     * @param {number} value
     * @returns {string}
     */
    formatAmount(value) {
        if (typeof value !== 'number' || isNaN(value)) return '0';
        const rounded = Math.round(value * 100) / 100;
        // Detect if the value is a whole number (IDR-style)
        const isWhole = (rounded % 1 === 0);
        if (isWhole) {
            // Format as integer with thousands dots: 29970000 → "29.970.000"
            return rounded.toFixed(0).replace(/\B(?=(\d{3})+(?!\d))/g, '.');
        }
        // Format with 2 decimals and thousands dots
        const [intPart, decPart] = rounded.toFixed(2).split('.');
        const formattedInt = intPart.replace(/\B(?=(\d{3})+(?!\d))/g, '.');
        return `${formattedInt},${decPart}`;
    }

    /**
     * Build a right-justified two-column line (label left, value right).
     * Total width = this.colWidth.
     *
     * @param {string} label
     * @param {string} value
     * @returns {string}
     */
    twoCol(label, value) {
        const w = this.colWidth;
        const v = String(value);
        const l = String(label);
        if (l.length + v.length >= w) {
            // Not enough room — put value on next implicit line via truncation
            return l.substring(0, w - v.length - 1).padEnd(w - v.length) + v;
        }
        return l + v.padStart(w - l.length);
    }

    /**
     * Divider line (full width).
     */
    divider() {
        return ''.padEnd(this.colWidth, '-');
    }

    // ─── Main receipt generator ──────────────────────────────────────────────

    /**
     * Generate complete receipt from structured data.
     *
     * Expected receiptData shape:
     * {
     *   headerData:  { companyName, address, phone, taxId }
     *   orderData:   { orderName, date, cashier, customer }
     *   lines:       [{ productName, quantity, price, total }, ...]
     *   totals:      { subtotal, tax, discount, total }
     *   paymentData: { method, amount, change }
     *   footerData:  { message, barcode }
     * }
     */
    generateReceipt(receiptData) {
        const cmds = [];
        const W = this.colWidth;

        // ── Initialize ────────────────────────────────────────────────────
        cmds.push(...this.initialize());

        // ── Header ────────────────────────────────────────────────────────
        // On basic receipt (table checker): skip company header, print only minimal info
        if (!receiptData.isBasicReceipt && receiptData.headerData) {
            const h = receiptData.headerData;
            if (h.companyName) {
                cmds.push(...this.addLine(h.companyName, { align: 'center', bold: true, width: 2, height: 2 }));
            }
            if (h.address) {
                cmds.push(...this.addLine(h.address, { align: 'center' }));
            }
            if (h.phone) {
                cmds.push(...this.addLine(h.phone, { align: 'center' }));
            }
            if (h.taxId) {
                cmds.push(...this.addLine(`NPWP: ${h.taxId}`, { align: 'center' }));
            }
            cmds.push(...this.addLine(this.divider()));
        }

        // ── Order info ────────────────────────────────────────────────────
        if (receiptData.orderData) {
            const o = receiptData.orderData;
            if (receiptData.isBasicReceipt) {
                // Basic receipt (table checker): all info at double height for readability
                if (o.orderName) cmds.push(...this.addLine(`Order: ${o.orderName}`, { height: 2, bold: true }));
                if (o.date)      cmds.push(...this.addLine(o.date, { height: 2 }));
                if (o.cashier)   cmds.push(...this.addLine(`By: ${o.cashier}`, { height: 2 }));
                if (o.tableName) cmds.push(...this.addLine(o.tableName, { bold: true, height: 2, align: 'center' }));
                if (o.customer)  cmds.push(...this.addLine(`Cust: ${o.customer}`, { height: 2 }));
            } else {
                if (o.orderName) cmds.push(...this.addLine(`Order: ${o.orderName}`));
                if (o.date)      cmds.push(...this.addLine(`Date:  ${o.date}`));
                if (o.cashier)   cmds.push(...this.addLine(`Cashier: ${o.cashier}`));
                if (o.tableName) cmds.push(...this.addLine(o.tableName, { bold: true, align: 'center' }));
                if (o.customer)  cmds.push(...this.addLine(`Customer: ${o.customer}`));
            }
            cmds.push(...this.addLine(this.divider()));
        }

        // ── Line items ────────────────────────────────────────────────────
        if (receiptData.lines && receiptData.lines.length > 0) {
            receiptData.lines.forEach(line => {
                const name = String(line.productName || '');
                const qty  = line.quantity || 0;
                const qtyStr = qty % 1 === 0 ? qty.toFixed(0) : qty.toFixed(2);

                if (receiptData.isBasicReceipt) {
                    // ── Basic receipt / table checker ──────────────────────────
                    // Show only qty + product name (no price/total), at double-width
                    // double-height for maximum readability on 58mm paper.
                    // At width=2, each char is 2x wide, so effective cols = W/2 = 16
                    const halfW = Math.floor(W / 2);
                    const qtyLabel = qtyStr.padEnd(2) + ' ';
                    const nameMaxLen = halfW - qtyLabel.length;
                    const displayName = name.length > nameMaxLen
                        ? name.substring(0, nameMaxLen - 1) + '.'
                        : name;
                    cmds.push(...this.addLine(qtyLabel + displayName, { bold: true, width: 2, height: 2 }));
                } else {
                    // ── Full receipt ───────────────────────────────────────────
                    // Line 1: product name
                    const displayName = name.length > W ? name.substring(0, W - 1) + '.' : name;
                    cmds.push(...this.addLine(displayName, { bold: true, height: 2 }));

                    // Line 2: qty x unitPrice = total (right-aligned)
                    const priceStr = this.formatAmount(line.price || 0);
                    const totalStr = this.formatAmount(line.total || 0);
                    const middle   = `${qtyStr}x ${priceStr}`;
                    let itemLine   = middle + totalStr.padStart(W - middle.length);
                    if (itemLine.length > W) itemLine = totalStr.padStart(W);
                    cmds.push(...this.addLine(itemLine, { bold: true, height: 2 }));
                }

                // Combo sub-lines detail printing (shown on both basic/checker and full receipt modes)
                if (line.comboLines && line.comboLines.length > 0) {
                    line.comboLines.forEach(sub => {
                        const subName = String(sub.productName || '');
                        const subQty = sub.quantity || 0;
                        const subQtyStr = subQty % 1 === 0 ? subQty.toFixed(0) : subQty.toFixed(2);

                        if (receiptData.isBasicReceipt) {
                            // Double-height sub-lines on basic receipt
                            const halfW = Math.floor(W / 2);
                            const prefix = ` ${subQtyStr}x `;
                            const maxSubLen = halfW - prefix.length;
                            const displaySub = subName.length > maxSubLen
                                ? subName.substring(0, maxSubLen - 1) + '.'
                                : subName;
                            cmds.push(...this.addLine(prefix + displaySub, { height: 2 }));
                        } else {
                            // Format: "  - 1x Mie Goreng"
                            const prefix = `  - ${subQtyStr}x `;
                            const maxSubLen = W - prefix.length;
                            const displaySub = subName.length > maxSubLen
                                ? subName.substring(0, maxSubLen - 1) + '.'
                                : subName;
                            cmds.push(...this.addLine(prefix + displaySub, { bold: true }));
                        }
                    });
                }

                // Note line (customer note / kitchen note) — word-wrapped to prevent truncation
                if (line.note) {
                    const rawNote = String(line.note);
                    const rawLines = rawNote.split('\n');
                    const wrappedLines = [];
                    const maxNoteWidth = W - 2;
                    
                    rawLines.forEach(rawLine => {
                        const words = rawLine.split(/\s+/);
                        let currentLine = '';
                        for (const word of words) {
                            if (!word) continue;
                            if ((currentLine + (currentLine ? ' ' : '') + word).length <= maxNoteWidth) {
                                currentLine += (currentLine ? ' ' : '') + word;
                            } else {
                                if (currentLine) {
                                    wrappedLines.push(currentLine);
                                }
                                let tempWord = word;
                                while (tempWord.length > maxNoteWidth) {
                                    wrappedLines.push(tempWord.substring(0, maxNoteWidth));
                                    tempWord = tempWord.substring(maxNoteWidth);
                                }
                                currentLine = tempWord;
                            }
                        }
                        if (currentLine) {
                            wrappedLines.push(currentLine);
                        }
                    });
                    
                    wrappedLines.forEach((l, i) => {
                        const prefix = i === 0 ? '* ' : '  ';
                        if (receiptData.isBasicReceipt) {
                            cmds.push(...this.addLine(prefix + l, { bold: true, height: 2 }));
                        } else {
                            cmds.push(...this.addLine(prefix + l, { bold: true }));
                        }
                    });
                }
            });
            cmds.push(...this.addLine(this.divider()));
        }

        // ── Totals ────────────────────────────────────────────────────────
        // Hidden on basic receipt — matches t-if="!props.basic_receipt" in order_receipt.xml
        if (!receiptData.isBasicReceipt && receiptData.totals) {
            const t = receiptData.totals;

            if (t.subtotal !== undefined) {
                cmds.push(...this.addLine(this.twoCol('Subtotal:', this.formatAmount(t.subtotal))));
            }
            if (t.discount !== undefined && t.discount > 0) {
                cmds.push(...this.addLine(this.twoCol('Discount:', this.formatAmount(t.discount))));
            }
            if (t.tax !== undefined && t.tax !== 0) {
                cmds.push(...this.addLine(this.twoCol('Tax:', this.formatAmount(t.tax))));
            }
            if (t.total !== undefined) {
                // Double-width/height for the grand total line
                const totalLabel = 'TOTAL:';
                const totalValue = this.formatAmount(t.total);
                // At 2x width the printer uses half the chars per line (W/2 = 16)
                const halfW = Math.floor(W / 2);
                const totalLine = totalLabel + totalValue.padStart(halfW - totalLabel.length);
                cmds.push(...this.addLine(totalLine, { bold: true, width: 2, height: 2 }));
            }
            cmds.push(...this.addLine(this.divider()));
        }

        // ── Payment ───────────────────────────────────────────────────────
        // Hidden on basic receipt — matches t-if="!props.basic_receipt" in order_receipt.xml
        if (!receiptData.isBasicReceipt && receiptData.paymentData) {
            const p = receiptData.paymentData;
            if (p.method) {
                cmds.push(...this.addLine(`Payment: ${p.method}`));
            }
            if (p.amount !== undefined) {
                cmds.push(...this.addLine(this.twoCol('Paid:', this.formatAmount(p.amount))));
            }
            if (p.change !== undefined && p.change > 0) {
                cmds.push(...this.addLine(this.twoCol('Change:', this.formatAmount(p.change)), { bold: true }));
            }
            cmds.push(...this.addLine(this.divider()));
        }

        // ── Footer ────────────────────────────────────────────────────────
        // Skip footer on basic receipt (table checker) — matches pos_custom_receipt behaviour
        if (!receiptData.isBasicReceipt && receiptData.footerData) {
            const f = receiptData.footerData;
            if (f.message) {
                cmds.push(...this.addLine(f.message, { align: 'center' }));
            }
            if (f.barcode) {
                cmds.push(...this.addLine(f.barcode, { align: 'center' }));
            }
        }

        // Feed and cut (set feed to 4 lines to ensure the footer clears the tear bar without excess blank space)
        cmds.push(...this.feedAndCut(4));

        return new Uint8Array(cmds);
    }

    /**
     * Helper: combine multiple Uint8Arrays into one.
     */
    static combineArrays(arrays) {
        const total  = arrays.reduce((s, a) => s + a.length, 0);
        const result = new Uint8Array(total);
        let offset   = 0;
        for (const arr of arrays) { result.set(arr, offset); offset += arr.length; }
        return result;
    }
}

export default EscPosGenerator;