react.c

#define CONCAT2(x, y) x ## y
#define CONCAT(x, y) CONCAT2(x, y)

#define COMPONENT(...)
#define DEFEVENT(...)
#define DEFBUBBLE(...)

struct context {
#define DEFCONTEXT(type, name, default) type name;
#include "components.i"
#undef DEFCONTEXT
};

struct context context_default(void) {
    struct context ctx;

#define DEFCONTEXT(type, name, default) ctx.name = default;
#include "components.i"
#undef DEFCONTEXT

    return ctx;
}
#define DEFCONTEXT(...)

// EVENTS & BUBBLES

#undef DEFEVENT
#undef DEFBUBBLE
#define DEFEVENT(name, ...) struct event_##name { __VA_ARGS__ }; const int event_##name = __LINE__;
#define DEFBUBBLE(name, ...) struct bubble_##name { __VA_ARGS__ };
#include "components.i"
#undef DEFEVENT
#undef DEFBUBBLE
#define DEFEVENT(...)
#define DEFBUBBLE(...)

#undef DEFBUBBLE
#define DEFBUBBLE(name, ...) struct { void *data; void (*fn)(void *data, struct bubble_##name *event); } name;
struct bubble_handlers {
#include "components.i"
};
#undef DEFBUBBLE
#define DEFBUBBLE(...)

#undef COMPONENT

#define PROP(...)
#define STATE(...)
#define ON(...)
#define CATCH(...)
#define LET(...)
#define PROVIDE(...)
#define USE(...)
#define INSTANCE(...)

// DEFINE PROPS
#define COMPONENT(name, ...) struct name##_props { __VA_ARGS__ };
#undef PROP
#define PROP(type, name) type name;
#include "components.i"
#undef PROP
#define PROP(...)
#undef COMPONENT

// DEFINE STATES
#define COMPONENT(name, ...) struct name##_state { struct name##_props ens_props; struct context ctx; __VA_ARGS__ };
#undef STATE
#define STATE(type, name, ...) type name;

#undef INSTANCE
#define INSTANCE(component, ...) int CONCAT(ens_state_count_, __LINE__); int CONCAT(ens_state_count_pre_, __LINE__); struct component##_state CONCAT(ens_state_, __LINE__)[8];

#undef USE
#define USE(component, ...) int CONCAT(ens_state_count_, __LINE__); int CONCAT(ens_state_count_pre_, __LINE__); struct component##_state CONCAT(ens_state_, __LINE__)[8];

#include "components.i"

#undef STATE
#define STATE(...)

#undef USE
#define USE(...)

#undef INSTANCE
#define INSTANCE(...)
#undef COMPONENT

// DEFINE DEINITS

#define COMPONENT(name, ...) void name##_deinit(struct name##_state *state) { __VA_ARGS__ };

#undef INSTANCE
#define INSTANCE(component, ...) for (int i = 0; i < state->CONCAT(ens_state_count_, __LINE__); i++) component##_deinit(&state->CONCAT(ens_state_, __LINE__)[i]);

#undef USE
#define USE(component, ...) for (int i = 0; i < state->CONCAT(ens_state_count_, __LINE__); i++) component##_deinit(&state->CONCAT(ens_state_, __LINE__)[i]);

#include "components.i"

#undef USE
#define USE(...)

#undef INSTANCE
#define INSTANCE(...)
#undef COMPONENT

// DEFINE DEFAULT

#define COMPONENT(name, ...) void name##_default(struct name##_state *state) { __VA_ARGS__ };

#undef STATE
#define STATE(type, name, ...) state->name = __VA_ARGS__;

#undef INSTANCE
#define INSTANCE(component, ...) state->CONCAT(ens_state_count_, __LINE__) = 0;

#undef USE
#define USE(component, ...) state->CONCAT(ens_state_count_, __LINE__) = 0;

#include "components.i"

#undef STATE
#define STATE(...)

#undef USE
#define USE(...)

#undef INSTANCE
#define INSTANCE(...)
#undef COMPONENT

// DECLARE

#define COMPONENT(name, ...) \
    struct context name##_build(struct name##_state *state, struct context ctx, struct name##_props props); \
    struct context name##_init(struct name##_state *state, struct context ctx, struct name##_props props);


#include "components.i"

#undef COMPONENT

// DEFINE PREBUILDS

#define COMPONENT(name, ...) void name##_prebuild(struct name##_state *state) { __VA_ARGS__ };

#undef INSTANCE
#define INSTANCE(component, ...) state->CONCAT(ens_state_count_pre_, __LINE__) = state->CONCAT(ens_state_count_, __LINE__); state->CONCAT(ens_state_count_, __LINE__) = 0;

#undef USE
#define USE(component, ...) state->CONCAT(ens_state_count_pre_, __LINE__) = state->CONCAT(ens_state_count_, __LINE__); state->CONCAT(ens_state_count_, __LINE__) = 0;

#include "components.i"

#undef USE
#define USE(...)

#undef INSTANCE
#define INSTANCE(...)
#undef COMPONENT

// DEFINE POSTBUILDS

#define COMPONENT(name, ...) void name##_postbuild(struct name##_state *state) { __VA_ARGS__ };

#undef INSTANCE
#define INSTANCE(component, ...) for (int i = state->CONCAT(ens_state_count_, __LINE__); i < state->CONCAT(ens_state_count_pre_, __LINE__); i++) { component##_deinit(&state->CONCAT(ens_state_, __LINE__)[i]); }

#undef USE
#define USE(component, ...) for (int i = state->CONCAT(ens_state_count_, __LINE__); i < state->CONCAT(ens_state_count_pre_, __LINE__); i++) { component##_deinit(&state->CONCAT(ens_state_, __LINE__)[i]); }

#include "components.i"

#undef USE
#define USE(...)

#undef INSTANCE
#define INSTANCE(...)
#undef COMPONENT

// DEFINE BUILDS

#define COMPONENT(name, ...) struct context name##_build(struct name##_state *state, struct context ctx, struct name##_props props) { name##_prebuild(state); __VA_ARGS__ name##_postbuild(state); state->ctx = ctx; return ctx; };

#undef STATE
#define STATE(type, name, ...) type name = state->name;

#undef PROP
#define PROP(type, name) type name = props.name;

#undef PROVIDE
#define PROVIDE(name, ...) ctx.name = __VA_ARGS__;

#undef LET
#define LET(type_value, ...) type_value = __VA_ARGS__;

#define CTX(name) ctx.name

#undef INSTANCE
#define INSTANCE(component, ...) if (state->CONCAT(ens_state_count_, __LINE__) < state->CONCAT(ens_state_count_, __LINE__)) { \
        component##_build(&state->CONCAT(ens_state_, __LINE__)[state->CONCAT(ens_state_count_, __LINE__)++], ctx, (struct component##_props) { __VA_ARGS__ }); \
    } else {                                                            \
        component##_init(&state->CONCAT(ens_state_, __LINE__)[state->CONCAT(ens_state_count_, __LINE__)++], ctx, (struct component##_props) { __VA_ARGS__ }); \
    }                                                                   \

#undef USE
#define USE(component, ...) if (state->CONCAT(ens_state_count_, __LINE__) < state->CONCAT(ens_state_count_, __LINE__)) { \
        ctx = component##_build(&state->CONCAT(ens_state_, __LINE__)[state->CONCAT(ens_state_count_, __LINE__)++], ctx, (struct component##_props) { __VA_ARGS__ }); \
    } else {                                                            \
        ctx = component##_init(&state->CONCAT(ens_state_, __LINE__)[state->CONCAT(ens_state_count_, __LINE__)++], ctx, (struct component##_props) { __VA_ARGS__ }); \
    }                                                                   \

#include "components.i"

#undef STATE
#define STATE(...)

#undef PROP
#define PROP(...)

#undef PROVIDE
#define PROVIDE(...)

#undef LET
#define LET(...)

#undef CTX
#define CTX(...)

#undef USE
#define USE(...)

#undef INSTANCE
#define INSTANCE(...)
#undef COMPONENT

// DEFINE INITS

#define COMPONENT(name, ...) struct context name##_init(struct name##_state *state, struct context ctx, struct name##_props props) { name##_default(state); name##_build(state, ctx, props); };
#include "components.i"
#undef COMPONENT

// EVENT HANDLERS

#define BUBBLE(x, ...) bubble_handlers.x.fn(bubble_handlers.x.data, &(struct bubble_##x) { __VA_ARGS__ });

#define COMPONENT(name, ...) __VA_ARGS__

#undef CATCH
#define CATCH(event, e, ...) void CONCAT(ens_bubble_handler_, __LINE__)(void *data, struct bubble_##event *e) { __VA_ARGS__ }

#include "components.i"

#undef CATCH
#define CATCH(...)
#undef COMPONENT

#undef CTX
#define CTX(name) state->ctx.name

#define COMPONENT(name, ...) void name##_event_i(struct name##_state *state, int event, void *event_data, struct bubble_handlers bubble_handlers) { __VA_ARGS__ } void name##_event(struct name##_state *state, int event, void *event_data) { name##_event_i(state, event, event_data, (struct bubble_handlers) { 0 }); name##_build(state, context_default(), state->ens_props); }

#undef STATE
#define STATE(type, name, ...) type *name = &state->name;

#undef ON
#define ON(ev, e, ...) if (event == event_##ev) { struct event_##ev *e = event_data; __VA_ARGS__ }

#undef CATCH
#define CATCH(ev, e, ...) bubble_handlers.ev.data = state; bubble_handlers.ev.fn = CONCAT(ens_bubble_handler_, __LINE__);

#undef USE
#define USE(component, ...) for (int i = 0; i < state->CONCAT(ens_state_count_, __LINE__); i++) { component##_event_i(&state->CONCAT(ens_state_, __LINE__)[i], event, event_data, bubble_handlers); }

#undef INSTANCE
#define INSTANCE(component, ...) for (int i = 0; i < state->CONCAT(ens_state_count_, __LINE__); i++) { component##_event_i(&state->CONCAT(ens_state_, __LINE__)[i], event, event_data, bubble_handlers); }

#include "components.i"

#undef ON
#define ON(...)
#undef COMPONENT

#undef DEFCONTEXT
#undef DEFEVENT
#undef DEFBUBBLE
#undef PROP
#undef STATE
#undef ON
#undef CATCH
#undef LET
#undef PROVIDE
#undef USE
#undef INSTANCE