// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Incoprea
// Migrate a version-one color field
// Not compiled or tested in-world
// Setup: Edit DOCUMENT and the example settings, then touch as owner. Requires simulator support for LSL JSON functions.
// Stop / restore: Remove or disable. JSON changes occur only in a local preview string.
// Notes: Only migrates the declared version and refuses an existing destination field. Retains unrelated fields; it does not persist or apply the configuration.
// License: see LICENSE in this distribution.
// Original Incoprea example. MIT.
string DOCUMENT="{\"version\":1,\"colour\":\"green\",\"title\":\"Lamp\"}";
string quoteJson(string value)
{
    string result="\"";
    string hex="0123456789abcdef";
    integer i;
    for(i=0;i<llStringLength(value);++i)
    {
        string c=llGetSubString(value,i,i);
        integer n=llOrd(value,i);
        if(c=="\"" || c=="\\")result+="\\"+c;
        else if(n<32)result+="\\u00"+llGetSubString(hex,n/16,n/16)+llGetSubString(hex,n%16,n%16);
        else result+=c;
    }
    return result+"\"";
}
default
{
    touch_start(integer touches)
    {
        if(llDetectedKey(0)!=llGetOwner())return;
        if(llJsonValueType(DOCUMENT,["version"])!=JSON_NUMBER || llJsonGetValue(DOCUMENT,["version"])!="1")
        {
            llOwnerSay("Expected version 1.");
            return;
        }
        if(llJsonValueType(DOCUMENT,["colour"])!=JSON_STRING || llJsonValueType(DOCUMENT,["color"])!=JSON_INVALID)
        {
            llOwnerSay("Invalid source or destination field collision.");
            return;
        }
        string result=llJsonSetValue(DOCUMENT,["color"],quoteJson(llJsonGetValue(DOCUMENT,["colour"])));
        result=llJsonSetValue(result,["colour"],JSON_DELETE);
        result=llJsonSetValue(result,["version"],"2");
        llOwnerSay(result);
    }
    changed(integer flags)
    {
        if(flags & CHANGED_OWNER)llResetScript();
    }
}