//---------------------------------------------------------------------------//
//  1100101 |_ mov #0, r4         __                                         //
//     11   |_ <0xb380 %5c4>     / _|_ _____ ___                             //
//     0110 |_ 3.50 -> 3.60     |  _\ \ / _ (_-<                             //
//          |_ base# + offset   |_| /_\_\___/__/                             //
//---------------------------------------------------------------------------//
// fxos/symbols: User-extensible naming scheme for OS objects
//
// This header provides tools to define symbols, ie. names attached to fixed or
// symbolic addresses. Currently supported:
//  - Address:  the name maps to a fixed 32-bit virtual address.
//  - Syscall:  the name maps to a syscall number resolved by OS analysis.
//
// The SymbolTable structure manages a set of symbols, usually all the symbols
// in a given virtual space.
//---

#ifndef FXOS_SYMBOLS_H
#define FXOS_SYMBOLS_H

#include <optional>
#include <string>
#include <vector>
#include <cstdint>

namespace FxOS {

/* A named symbol that can be substituted to literal values in the code. */
struct Symbol
{
    enum Type { Syscall = 1, Address = 2 };

    enum Type type;
    uint32_t value;

    /* Symbol name, no particular conventions */
    std::string name;

    bool operator<(const FxOS::Symbol &right) const
    {
        return (type < right.type)
               || (value < right.value && type == right.type);
    }

    bool operator>(const FxOS::Symbol &right) const
    {
        return (type > right.type)
               || (value > right.value && type == right.type);
    }

    bool operator==(const FxOS::Symbol &right) const
    {
        return value == right.value && type == right.type;
    }

    bool operator!=(const FxOS::Symbol &right) const
    {
        return value != right.value || type != right.type;
    }

    bool operator>=(const FxOS::Symbol &right) const
    {
        return (type > right.type)
               || (value >= right.value && type == right.type);
    }

    bool operator<=(const FxOS::Symbol &right) const
    {
        return (type < right.type)
               || (value <= right.value && type == right.type);
    }
};

/* A symbol table, usually the set of symbols of a virtual space */
struct SymbolTable
{
    SymbolTable();

    /* Allow move but disable copy */
    SymbolTable(SymbolTable const &other) = delete;
    SymbolTable(SymbolTable &&other) = default;

    std::string table_name;
    std::vector<Symbol> symbols;

    /* Add a symbol to the table */
    void add(Symbol s);
    /* Query a value for a certain type of symbol */
    std::optional<std::string> query(Symbol::Type type, uint32_t value) const;
    /* Lookup the symbol behind a given name */
    std::optional<Symbol> lookup(std::string name) const;
};

} /* namespace FxOS */

#endif /* FXOS_SYMBOLS_H */