/*
 * SPDX-License-Identifier: LGPL-2.0-or-later
 *
 * PlumbMsg — a plan9port plumbing message and its wire codec.
 *
 * A plumb message is a context-carrying request routed by the plumber daemon
 * through named ports. The wire format (plan9port libplumb/mesg.c) is six
 * newline-terminated header lines followed by the raw data bytes:
 *
 *     src\n            source application ("kate")
 *     dst\n            destination port ("" lets the rules decide)
 *     wdir\n           working directory (resolves relative paths)
 *     type\n           data type ("text")
 *     attr\n           space-separated name=value attributes
 *     ndata\n          decimal byte count of the data that follows
 *     <ndata bytes>    the data (NOT newline-terminated)
 *
 * Attribute values containing space, tab, '=' or ' are single-quoted, with a
 * literal ' escaped by doubling it ('') — exactly as libplumb quotes them.
 *
 * This header is pure (QString/QByteArray only) so pack/unpack can be unit
 * tested against the bytes captured from a live plumber on the edit port.
 */
#ifndef KATECUSTOM_PLUMBMSG_H
#define KATECUSTOM_PLUMBMSG_H

#include <QByteArray>
#include <QList>
#include <QString>

namespace katecustom
{

/*! One plumb attribute (name=value). */
struct PlumbAttr {
    QString name;
    QString value;
    bool operator==(const PlumbAttr &o) const
    {
        return name == o.name && value == o.value;
    }
};

/*! A decoded plumb message. */
struct PlumbMsg {
    QString src;
    QString dst;
    QString wdir;
    QString type;
    QList<PlumbAttr> attr;
    QByteArray data;

    /*! Value of attribute \a name, or empty QString if absent. */
    QString lookup(const QString &name) const;

    /*! Set (or replace) attribute \a name to \a value. */
    void setAttr(const QString &name, const QString &value);

    /*!
     * Encode to the libplumb wire format. The attribute list is serialised with
     * libplumb-compatible quoting. ndata is the byte length of \c data.
     */
    QByteArray pack() const;

    /*!
     * Decode \a buf (a complete message) into \a out. Returns true on success.
     * Mirrors libplumb plumbunpackpartial: parses six header lines, then takes
     * exactly the trailing bytes as data (libplumb clamps ndata to what was
     * actually received, so a short ndata header is tolerated the same way).
     */
    static bool unpack(const QByteArray &buf, PlumbMsg *out);
};

/*! Serialise an attribute list with libplumb quoting rules (exposed for tests). */
QByteArray packPlumbAttr(const QList<PlumbAttr> &attr);

/*! Parse a packed attribute line back into a list (exposed for tests). */
QList<PlumbAttr> unpackPlumbAttr(const QByteArray &line);

} // namespace katecustom

#endif