json-joy/esm/json-patch-ot/transforms/xStrIns.js

Collection of libraries for building collaborative editing apps.

import { operationToOp } from '../../json-patch/codec/json';
import { OpStrDel, OpStrIns } from '../../json-patch/op';
export const xStrIns = (ins, op) => {
    if (op instanceof OpStrIns) {
        if (ins.pos > op.pos)
            return op;
        return operationToOp({ ...op.toJson(), pos: op.pos + ins.str.length }, {});
    }
    else if (op instanceof OpStrDel) {
        const del = op;
        if (del.pos < ins.pos) {
            const deleteLength = typeof del.str === 'string' ? del.str.length : del.len;
            if (del.pos + deleteLength > ins.pos) {
                const beforeLength = ins.pos - del.pos;
                if (typeof del.str === 'string') {
                    return [
                        operationToOp({ ...del.toJson(), pos: ins.pos + ins.str.length, str: del.str.substr(beforeLength) }, {}),
                        operationToOp({ ...del.toJson(), pos: del.pos, str: del.str.substr(0, beforeLength) }, {}),
                    ];
                }
                else {
                    return [
                        operationToOp({ ...del.toJson(), pos: ins.pos + ins.str.length, len: deleteLength - beforeLength }, {}),
                        operationToOp({ ...del.toJson(), pos: del.pos, len: beforeLength }, {}),
                    ];
                }
            }
        }
        if (ins.pos < del.pos)
            return operationToOp({ ...op.toJson(), pos: op.pos + ins.str.length }, {});
        return op;
    }
    return op;
};