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/*! sheetjs (C) 2013-present SheetJS -- http://sheetjs.com */import { Ptr, parse_varint49, write_varint49 } from './proto';import { u8concat } from './util';
function is_framed(buf: Uint8Array): boolean {	var l = 0;	while(l < buf.length) {		l++;		var len = buf[l] | (buf[l+1]<<8) | (buf[l+2] << 16); l += 3;		l += len;	}	return l == buf.length;}export { is_framed };
function deframe(buf: Uint8Array): Uint8Array {	var out = [];	var l = 0;	while(l < buf.length) {		var t = buf[l++];		var len = buf[l] | (buf[l+1]<<8) | (buf[l+2] << 16); l += 3;		out.push(parse_snappy_chunk(t, buf.slice(l, l + len)));		l += len;	}	if(l !== buf.length) throw new Error("data is not a valid framed stream!");	return u8concat(out);}export { deframe };
function reframe(buf: Uint8Array): Uint8Array {	var out: Uint8Array[] = [];	var l = 0;	while(l < buf.length) {		var c = Math.min(buf.length - l, 0xFFFFFFF);		var frame = new Uint8Array(4);		out.push(frame);		var usz = write_varint49(c);		var L = usz.length;		out.push(usz);
		if(c <= 60) { L++; out.push(new Uint8Array([(c - 1)<<2])); }		else if(c <= 0x100)       { L += 2; out.push(new Uint8Array([0xF0, (c-1) & 0xFF])); }		else if(c <= 0x10000)     { L += 3; out.push(new Uint8Array([0xF4, (c-1) & 0xFF, ((c-1) >> 8) & 0xFF])); }		else if(c <= 0x1000000)   { L += 4; out.push(new Uint8Array([0xF8, (c-1) & 0xFF, ((c-1) >> 8) & 0xFF, ((c-1) >> 16) & 0xFF])); }		else if(c <= 0x100000000) { L += 5; out.push(new Uint8Array([0xFC, (c-1) & 0xFF, ((c-1) >> 8) & 0xFF, ((c-1) >> 16) & 0xFF, ((c-1) >>> 24) & 0xFF])); }
		out.push(buf.slice(l, l + c)); L += c;
		frame[0] = 0;		frame[1] = L & 0xFF; frame[2] = (L >>  8) & 0xFF; frame[3] = (L >> 16) & 0xFF;		l += c;	}	return u8concat(out);}export { reframe };
function parse_snappy_chunk(type: number, buf: Uint8Array): Uint8Array {	if(type != 0) throw new Error(`Unexpected Snappy chunk type ${type}`);	var ptr: Ptr = [0];
	var usz = parse_varint49(buf, ptr);	var chunks = [];	while(ptr[0] < buf.length) {		var tag = buf[ptr[0]] & 0x3;		if(tag == 0) {			var len = buf[ptr[0]++] >> 2;			if(len < 60) ++len;			else {				var c = len - 59;				len = buf[ptr[0]];				if(c > 1) len |= (buf[ptr[0]+1]<<8);				if(c > 2) len |= (buf[ptr[0]+2]<<16);				if(c > 3) len |= (buf[ptr[0]+3]<<24);				len >>>=0; len++;				ptr[0] += c;			}			chunks.push(buf.slice(ptr[0], ptr[0] + len)); ptr[0] += len; continue;		} else {			var offset = 0, length = 0;			if(tag == 1) {				length = ((buf[ptr[0]] >> 2) & 0x7) + 4;				offset = (buf[ptr[0]++] & 0xE0) << 3;				offset |= buf[ptr[0]++];			} else {				length = (buf[ptr[0]++] >> 2) + 1;				if(tag == 2) { offset = buf[ptr[0]] | (buf[ptr[0]+1]<<8); ptr[0] += 2; }				else { offset = (buf[ptr[0]] | (buf[ptr[0]+1]<<8) | (buf[ptr[0]+2]<<16) | (buf[ptr[0]+3]<<24))>>>0; ptr[0] += 4; }			}			chunks = [u8concat(chunks)];			if(offset == 0) throw new Error("Invalid offset 0");			if(offset > chunks[0].length) throw new Error("Invalid offset beyond length");			if(length >= offset) {				chunks.push(chunks[0].slice(-offset)); length -= offset;				while(length >= chunks[chunks.length-1].length) {					chunks.push(chunks[chunks.length - 1]);					length -= chunks[chunks.length - 1].length;				}			}			chunks.push(chunks[0].slice(-offset, -offset + length));		}	}	var o = u8concat(chunks);	if(o.length != usz) throw new Error(`Unexpected length: ${o.length} != ${usz}`);	return o;}