/**
 ** \file task/libtask.hh
 ** \brief Interface to the Task module.
 **
 */

/* This file must not be protected against multiple inclusion,
   because it might be read to define or declare the tasks. */

#include <task/boolean-task.hh>
#include <task/disjunctive-task.hh>
#include <task/function-task.hh>
#include <task/int-task.hh>
#include <task/multiple-string-task.hh>
#include <task/string-task.hh>

/// Handling of Task.
namespace task
{} // namespace task

/** A means to concatenate tokens with delayed evaluation. */
#define CONCAT_(A, B) A##B
#define CONCAT(A, B) CONCAT_(A, B)

/** Make a "unique" token using the line number of invocation of this
    macro.

    Conflicts are possible, but unlikely: tasks declared at the same
    line number, but in different files, are not a problem, since
    anyway the tasks are static, and in different namespaces.

    Just don't declare two tasks on the same line! */
#define TASK_UNIQUE() CONCAT(task_, __LINE__)

/*------------------------------.
| Easy instantiation of Tasks.  |
`------------------------------*/

#undef TASK_GROUP
#undef TASK_DECLARE
#undef BOOLEAN_TASK_DECLARE
#undef INT_TASK_DECLARE
#undef STRING_TASK_DECLARE
#undef MULTIPLE_STRING_TASK_DECLARE
#undef DISJUNCTIVE_TASK_DECLARE

// Should we define the objects, or just declare them?
#if DEFINE_TASKS

/// Define the current Task group name.
#  define TASK_GROUP(Name) const char group_name[] = Name

/// Instantiate a FunctionTask.
#  define TASK_DECLARE(Name, Help, Routine, Deps)                              \
    extern void(Routine)();                                                    \
    static task::FunctionTask task_##Routine(Routine, group_name, Help, Name,  \
                                             Deps)

/// Instantiate a BooleanTask.
#  define BOOLEAN_TASK_DECLARE(Name, Help, Flag, Deps)                         \
    bool Flag;                                                                 \
    static task::BooleanTask task_##Flag(Flag, group_name, Help, Name, Deps)

#  define TASK_UNIQUE_NAME_(Line) task_##Line

#  define TASK_UNIQUE_NAME TASK_UNIQUE_NAME_(__LINE__)

/// Instantiate an IntTask.
#  define INT_TASK_DECLARE(Name, Min, Max, Help, Flag, Deps)                   \
    static task::IntTask TASK_UNIQUE()(Flag, Min, Max, group_name, Help, Name, \
                                       Deps)

/// Instantiate a StringTask.
#  define STRING_TASK_DECLARE(Name, Default, Help, Flag, Deps)                 \
    std::string Flag = Default;                                                \
    static task::StringTask task_##Flag(Flag, group_name, Help, Name, Deps)

/// Instanciate a MultipleStringTask
#  define MULTIPLE_STRING_TASK_DECLARE(Name, Help, Routine, Deps)              \
    extern task::MultipleStringTask::callback_type Routine;                    \
    static task::MultipleStringTask task_##Routine(Routine, group_name, Help,  \
                                                   Name, Deps)

/// Instantiate a DisjunctiveTask.
#  define DISJUNCTIVE_TASK_DECLARE(Name, Help, Deps)                           \
    static task::DisjunctiveTask task_##Routine(group_name, Help, Name, Deps)

#else // !DEFINE_TASKS

/// Define the current Task group name.
#  define TASK_GROUP(Name) extern const char* group_name
/// Instantiate a FunctionTask.
#  define TASK_DECLARE(Name, Help, Routine, Deps) extern void(Routine)()
/// Instantiate a BooleanTask.
#  define BOOLEAN_TASK_DECLARE(Name, Help, Flag, Deps) extern bool Flag;
/// Instantiate an IntTask.
#  define INT_TASK_DECLARE(Name, Min, Max, Help, Flag, Deps)
/// Instantiate a StringTask.
#  define STRING_TASK_DECLARE(Name, Default, Help, Flag, Deps)                 \
    extern std::string Flag;
/// Instantiate a MultipleStringTask.
#  define MULTIPLE_STRING_TASK_DECLARE(Name, Help, Routine, Deps)              \
    extern void(Routine)(std::string);
/// Instantiate a DisjunctiveTask.
#  define DISJUNCTIVE_TASK_DECLARE(Name, Help, Deps)

#endif // !DEFINE_TASKS