/**
 *  ops/apply.c
 *
 *  Post Scarcity Software Environment: apply.
 *
 *  Add a applying for a key/value pair to a store -- at this stage, just an
 *  association list.
 *
 *  (c) 2026 Simon Brooke <simon@journeyman.cc>
 *  Licensed under GPL version 2.0, or, at your option, any later version.
 */

#include "memory/node.h"
#include "memory/pointer.h"
#include "memory/pso.h"
#include "memory/pso3.h"
#include "memory/pso4.h"
#include "memory/tags.h"

#include "ops/assoc.h"
#include "ops/stack_ops.h"
#include "ops/string_ops.h"
#include "ops/truth.h"

#include "payloads/cons.h"
#include "payloads/stack.h"

/**
 * @brief Apply a function to arguments in an environment.
 *
 * * (apply fn args) 
 */
struct pso_pointer apply(
#ifndef MANAGED_POINTER_ONLY
                             struct pso4 *frame,
#endif
                             struct pso_pointer frame_pointer,
                             struct pso_pointer env ) {
#ifdef MANAGED_POINTER_ONLY
    struct pso4 *frame = pointer_to_pso4( frame_pointer );
#endif

// TODO.

}

/**
 * @brief Evaluate a form, in an environment
 *
 * * (eval form) 
 */
struct pso_pointer eval(
#ifndef MANAGED_POINTER_ONLY
                            struct pso4 *frame,
#endif
                            struct pso_pointer frame_pointer,
                            struct pso_pointer env ) {
#ifdef MANAGED_POINTER_ONLY
    struct pso4 *frame = pointer_to_pso4( frame_pointer );
#endif
    struct pso_pointer result = fetch_arg( frame, 0 );

    switch ( get_tag_value( result ) ) {
            //     case CONSTV:
            //         result = eval_cons( frame, frame_pointer, env);
            //         break;
        case INTEGERTV:
        case KEYTV:
        case STRINGTV:
            // self evaluating
            break;
        case SYMBOLTV:
            result = c_assoc( result, env );
            break;
            //     case LAMBDATV:
            //         result = eval_lambda( frame, frame_pointer, env);
            //         break;
            //     case NLAMBDATV:
            //         result = eval_nlambda( frame, frame_pointer, env);
            //         break;
            //     case SPECIALTV:
            //         result = eval_special( frame, frame_pointer, env);
            //         break;
        default:
            result =
                make_exception( c_cons
                                ( c_string_to_lisp_string
                                  ( L"Can't yet evaluate things of this type: " ),
                                  result ), frame_pointer,
								  c_cons( c_cons( c_string_to_lisp_keyword(L"tag"),
										  get_tag_string(result)), nil), nil );
    }

    if ( exceptionp( result ) ) {
        struct pso3 *x =
            ( struct pso3 * ) pointer_to_object_with_tag_value( result,
                                                                EXCEPTIONTV );

        if ( nilp( x->payload.exception.stack ) ) {
            result =
                make_exception( x->payload.exception.message, frame_pointer, nil,
                                result );
        }
    }

    return result;
}