control.hh

#pragma once
 
#include <clingo/backend.hh>
#include <clingo/base.hh>
#include <clingo/config.hh>
#include <clingo/core.hh>
#include <clingo/observe.hh>
#include <clingo/propagate.hh>
#include <clingo/solve.hh>
#include <clingo/stats.hh>
#include <clingo/symbol.hh>
 
#include <clingo/control.h>
 
#include <cassert>
#include <optional>
#include <span>
 
namespace Clingo {
 
namespace AST {
 
class Program;
auto c_cast(Program const &x) -> clingo_program_t *;
 
} // namespace AST
 
namespace Detail {
 
void join(clingo_control_t *ctx, clingo_program_t const *prg);
 
} // namespace Detail
 
 
struct Part {
    Part(std::string name, SymbolVector params = {}) : name{std::move(name)}, params(std::move(params)) {
        assert(!this->name.empty());
    }
 
    std::string name;
    SymbolVector params;
};
using PartSpan = std::span<Part const>;
using PartList = std::initializer_list<Part>;
using PartVector = std::vector<Part>;
 
class ConstMap {
  public:
    using key_type = std::string_view;
    using mapped_type = Symbol;
    using value_type = std::pair<key_type, mapped_type>;
    using size_type = std::size_t;
    using difference_type = std::ptrdiff_t;
    using reference = value_type;
    using pointer = Detail::ArrowProxy<value_type>;
    using iterator = Detail::RandomAccessIterator<ConstMap>;
 
    explicit ConstMap(clingo_const_map_t const *map) : map_{map} {}
 
    [[nodiscard]] auto contains(key_type name) const -> bool {
        return Detail::call<clingo_const_map_find>(map_, name.data(), name.size(), nullptr);
    }
 
    [[nodiscard]] auto operator[](key_type name) const -> mapped_type {
        clingo_symbol_t sym = 0;
        bool found = false;
        Detail::handle_error(clingo_const_map_find(map_, name.data(), name.size(), &sym, &found));
        return found ? Symbol{sym, true} : throw std::out_of_range{"key not found"};
    }
 
    [[nodiscard]] auto at(size_t index) const -> value_type {
        clingo_string_t name;
        clingo_symbol_t sym = 0;
        Detail::handle_error(clingo_const_map_at(map_, index, &name, &sym));
        return {{name.data, name.size}, Symbol{sym, true}};
    }
 
    [[nodiscard]] auto size() const -> size_type { return Detail::call<clingo_const_map_size>(map_); }
 
    [[nodiscard]] auto begin() const -> iterator { return iterator{*this, 0}; }
 
    [[nodiscard]] auto end() const -> iterator { return iterator{*this, size()}; }
 
  private:
    clingo_const_map_t const *map_;
};
 
enum class ControlMode : clingo_mode_t {
    parse = clingo_mode_parse,     
    rewrite = clingo_mode_rewrite, 
    ground = clingo_mode_ground,   
    solve = clingo_mode_solve,     
};
 
enum class WriteAspifFlags : clingo_write_aspif_mode_t {
    none = 0,                                              
    preamble = clingo_write_aspif_mode_preamble,           
    preamble_auto = clingo_write_aspif_mode_preamble_auto, 
    append = clingo_write_aspif_mode_append,               
    preprocess = clingo_write_aspif_mode_preprocess,       
    symbols = clingo_write_aspif_mode_symbols,             
};
CLINGO_ENABLE_BITSET_ENUM(WriteAspifFlags);
 
enum class SolveFlags : clingo_solve_mode_bitset_t {
    empty = 0,                       
    yield = clingo_solve_mode_yield, 
    async = clingo_solve_mode_async, 
};
CLINGO_ENABLE_BITSET_ENUM(SolveFlags);
 
enum class DiscardType {
    minimize = clingo_discard_type_e::minimize, 
    project = clingo_discard_type_e::project,   
};
 
class Control {
  public:
    using Context = std::function<SymbolVector(std::string_view, SymbolSpan)>;
 
    explicit Control(Library const &lib, StringList arguments) : Clingo::Control{lib, StringSpan{arguments}} {}
 
    explicit Control(Library const &lib, StringSpan arguments = {}) {
        auto cstrs = Detail::transform(arguments, [](auto const &x) { return clingo_string_t{x.data(), x.size()}; });
        ctl_.reset(Detail::call<clingo_control_new>(c_cast(lib), cstrs.data(), arguments.size()), false);
    }
 
    explicit Control(clingo_control_t *rep, bool acquire) : ctl_{rep, acquire} {}
 
    [[nodiscard]] friend auto c_cast(Control const &ctl) -> clingo_control_t * { return ctl.ctl_.get(); }
 
    [[nodiscard]] auto mode() const -> ControlMode {
        return static_cast<ControlMode>(Detail::call<clingo_control_mode>(ctl_.get()));
    }
 
    void write_aspif(std::string_view path, WriteAspifFlags flags = WriteAspifFlags::none) const {
        Detail::handle_error(clingo_control_write_aspif(ctl_.get(), path.data(), path.size(),
                                                        static_cast<clingo_write_aspif_mode_t>(flags)));
    }
 
    void parse_files(StringSpan files) const {
        auto cfiles = Detail::transform(files, [](auto const &x) { return clingo_string_t{x.data(), x.size()}; });
        Detail::handle_error(clingo_control_parse_files(ctl_.get(), cfiles.data(), cfiles.size()));
    }
 
    void parse_files(StringList files) const { parse_files(StringSpan{files.begin(), files.end()}); }
 
    void parse_string(std::string_view program) const {
        Detail::handle_error(clingo_control_parse_string(ctl_.get(), program.data(), program.size()));
    }
 
    void ground(std::optional<PartSpan> parts = std::nullopt, Context ctx = nullptr) const {
        std::optional<PartVector> default_parts;
        std::vector<clingo_part_t> c_parts;
        if (default_parts = !parts ? this->parts() : std::nullopt; default_parts) {
            parts = default_parts;
        }
        if (parts) {
            c_parts.reserve(parts->size());
            for (auto const &part : *parts) {
                c_parts.emplace_back(part.name.data(), part.name.size(), c_cast(part.params.data()),
                                     part.params.size());
            }
        } else {
            c_parts.reserve(1);
            c_parts.emplace_back("base", 4, nullptr, 0);
        }
        Detail::handle_error(
            clingo_control_ground(ctl_.get(), c_parts.data(), c_parts.size(), ctx ? &ctx_ : nullptr, &ctx));
    }
 
    void ground(std::initializer_list<Part> parts, Context ctx = nullptr) const {
        ground(PartSpan{parts}, std::move(ctx));
    }
 
    [[nodiscard]] auto base() const -> Base { return Base{Detail::call<clingo_control_base>(ctl_.get())}; }
 
    [[nodiscard]] auto stats() const -> ConstStats {
        auto const *stats = Detail::call<clingo_control_stats>(ctl_.get());
        auto key = Detail::call<clingo_stats_root>(stats);
        return ConstStats{stats, key};
    }
 
    [[nodiscard]] auto solve(SolveEventHandler &handler, ProgramLiteralSpan const &assumptions = {},
                             SolveFlags flags = SolveFlags::empty) const -> SolveHandle {
        return solve_(&handler, assumptions, flags);
    }
 
    [[nodiscard]] auto solve(ProgramLiteralSpan const &assumptions = {}, SolveFlags flags = SolveFlags::yield) const
        -> SolveHandle {
        return solve_(nullptr, assumptions, flags);
    }
 
    void main() const { Detail::handle_error(clingo_control_main(ctl_.get())); }
 
    void interrupt() const { clingo_control_interrupt(ctl_.get()); }
 
    void discard(DiscardType type) const {
        Detail::handle_error(clingo_control_discard(ctl_.get(), static_cast<clingo_discard_type_t>(type)));
    }
 
    [[nodiscard]] auto buffer() const -> std::string_view {
        auto [data, size] = Detail::call<clingo_control_buffer>(ctl_.get());
        return {data, size};
    }
 
    [[nodiscard]] auto parts() const -> std::optional<PartVector> {
        clingo_part_t const *parts = nullptr;
        size_t size = 0;
        bool has_value = false;
        Detail::handle_error(clingo_control_get_parts(ctl_.get(), &parts, &size, &has_value));
        if (has_value) {
            return Detail::transform(std::span{parts, size}, [](auto const &part) {
                auto params = std::span{cpp_cast(part.params), part.params_size};
                return Part{{part.name, part.name_size}, {params.begin(), params.end()}};
            });
        }
        return std::nullopt;
    }
 
    void parts(PartList parts) const { this->parts(std::span{parts.begin(), parts.end()}); }
 
    void parts(std::optional<PartSpan> parts) const {
        if (parts) {
            auto cparts = Detail::transform(*parts, [](auto const &part) {
                return clingo_part_t{part.name.data(), part.name.size(), c_cast(part.params.data()),
                                     part.params.size()};
            });
            Detail::handle_error(clingo_control_set_parts(ctl_.get(), cparts.data(), cparts.size(), true));
        } else {
            Detail::handle_error(clingo_control_set_parts(ctl_.get(), nullptr, 0, true));
        }
    }
 
    [[nodiscard]] auto config() const -> Config {
        auto *config = Detail::call<clingo_control_config>(ctl_.get());
        auto key = Detail::call<clingo_config_root>(config);
        return Config{config, key};
    }
 
    [[nodiscard]] auto const_map() const -> ConstMap {
        return ConstMap{Detail::call<clingo_control_const_map>(ctl_.get())};
    }
 
    void observe(Observer &obs, bool preprocess = true) const { obs.observe(ctl_.get(), preprocess); }
 
    [[nodiscard]] auto backend() const -> ProgramBackend {
        return ProgramBackend{Detail::call<clingo_control_backend>(ctl_.get())};
    }
 
    template <std::derived_from<Propagator> T> auto register_propagator(std::unique_ptr<T> propagator) const -> T & {
        assert(propagator != nullptr);
        auto &res = *propagator;
        Detail::handle_error(clingo_control_register_propagator(
            ctl_.get(), std::is_base_of_v<Heuristic, T> ? &Detail::c_heuristic : &Detail::c_propagator,
            propagator.release()));
        return res;
    }
 
    void join(AST::Program const &prg) const { Detail::join(ctl_.get(), c_cast(prg)); }
 
  private:
    friend class Detail::intrusive_handle<Control, clingo_control_t>;
 
    static auto ctx_([[maybe_unused]] clingo_lib_t *lib, [[maybe_unused]] clingo_location_t const *location,
                     char const *name, size_t name_size, clingo_symbol_t const *arguments, size_t arguments_size,
                     void *data, clingo_symbol_callback_t symbol_callback, void *symbol_callback_data) -> bool {
        CLINGO_TRY {
            auto &cb = *static_cast<std::function<SymbolVector(std::string_view, SymbolSpan)> *>(data);
            auto syms = cb({name, name_size}, {cpp_cast(arguments), arguments_size});
            auto const *c_syms = c_cast(syms.data());
            return symbol_callback(c_syms, syms.size(), symbol_callback_data);
        }
        CLINGO_CATCH;
    }
 
    static auto acquire(clingo_control_t *ptr) { clingo_control_acquire(ptr); }
 
    static auto release(clingo_control_t *ptr) { clingo_control_release(ptr); }
 
    [[nodiscard]] auto solve_(SolveEventHandler *handler, ProgramLiteralSpan const &assumptions, SolveFlags flags) const
        -> SolveHandle {
        clingo_solve_handle_t *res = nullptr;
        Detail::handle_error(clingo_control_solve(ctl_.get(), static_cast<clingo_solve_mode_bitset_t>(flags),
                                                  assumptions.data(), assumptions.size(),
                                                  handler != nullptr ? &Detail::c_solve_event_handler : nullptr,
                                                  handler != nullptr ? handler : nullptr, &res));
        return SolveHandle{res};
    }
 
    Detail::intrusive_handle<Control, clingo_control_t> ctl_;
};
 
 
} // namespace Clingo