/**
 * A simple ESC/POS encoder for thermal printers
 */
export class EscPosEncoder {
    private encoder = new TextEncoder();
    private buffer: number[] = [];

    constructor() {}

    /**
     * Initialize printer
     */
    initialize(): this {
        this.buffer.push(0x1b, 0x40);
        return this;
    }

    /**
     * Write text
     */
    text(value: string): this {
        const bytes = this.encoder.encode(value);
        this.buffer.push(...Array.from(bytes));
        return this;
    }

    /**
     * Write text with newline
     */
    line(value: string = ''): this {
        this.text(value + '\n');
        return this;
    }

    /**
     * Set alignment
     * 0: left, 1: center, 2: right
     */
    align(value: 0 | 1 | 2): this {
        this.buffer.push(0x1b, 0x61, value);
        return this;
    }

    /**
     * Set bold
     */
    bold(value: boolean): this {
        this.buffer.push(0x1b, 0x45, value ? 1 : 0);
        return this;
    }

    /**
     * Set font size
     * 0: normal, 1: double height, 2: double width, 3: double height + width
     */
    size(value: 0 | 1 | 2 | 3): this {
        let size = 0;
        if (value === 1) size = 0x01;
        if (value === 2) size = 0x10;
        if (value === 3) size = 0x11;
        this.buffer.push(0x1d, 0x21, size);
        return this;
    }

    /**
     * Feed and cut
     */
    cut(): this {
        this.buffer.push(0x1d, 0x56, 0x00);
        return this;
    }

    /**
     * Feed lines
     */
    feed(lines: number = 1): this {
        this.buffer.push(0x1b, 0x64, lines);
        return this;
    }

    /**
     * Get the encoded bytes
     */
    encode(): Uint8Array {
        return new Uint8Array(this.buffer);
    }
}