#include "tstring.h"
#include "string.h"
#include "stdlib.h"
#include "stdio.h"

void generator(
	tstring* header_filename,
	tstring* source_filename,
	tstring* prefix, 
	tstring* bucket_count,
	tstring* K_size, tstring* K_comp_pred, tstring* K_hash_func,
	tstring* V_size
) {
	tstring* key_type = tstring_n_compose("tc",
		prefix, "_key_t"
	);
	tstring* key_type_decl = tstring_n_compose("ctctc",
		"struct ", key_type, "{\n"
			"char* data[",K_size,"];\n"
		"};\n"
	);
	tstring* value_type = tstring_n_compose("tc",
		prefix, "_value_t"
	);
	tstring* value_type_decl = tstring_n_compose("ctctc",
		"struct ", value_type, "{\n"
			"char* data[",V_size,"];\n"
		"};\n"
	);
	tstring* accessor_type = tstring_n_compose("tc",
		prefix, "_accessor_t"
	);
	tstring* accessor_type_decl = tstring_n_compose("ctc",
		"struct ", accessor_type, "{\n"
			"void* value;\n"
		"};\n"
	);
	tstring* hash_decl = tstring_n_compose("ctctctctc",
		"size_t ",K_hash_func,"(void*);\n"
		"struct ",prefix,"_hashtype{\n"
		"size_t operator()(const ",key_type,"& key) {\n"
			"return ", K_hash_func, "((void*)&key);\n"
		"}\n"
		"};\n"
	);
	tstring* hash_type = tstring_n_compose("tc",
		prefix,"_hashtype"
	);
	tstring* hashmap_ptr_type = tstring_n_compose("tc",
		prefix,"_hashmap_ptr"
	);
	tstring* hashmap_decl = tstring_n_compose("ctc",
		"typedef void* ",hashmap_ptr_type,";\n"
	);
	tstring* cpp_hashmap_type = tstring_n_compose("ctctctctc",
		"mct20::lfhmap<",key_type,",",value_type,",",bucket_count,",",hash_type,">"
	);
	tstring* cpp_hashmap_ptr_type = tstring_n_compose("tc",
		cpp_hashmap_type,"*"
	);
	
	tstring* create_hashmap_decl = tstring_n_compose("tctc",
		hashmap_ptr_type," ",prefix,"_hm_create();\n"
	);
	tstring* destroy_hashmap_decl = tstring_n_compose("ctctc",
		"void ", prefix, "_hm_destroy(",hashmap_ptr_type,");\n"
	);
	tstring* hashmap_push_decl = tstring_n_compose("ctctctctc",
		"void ", prefix, "_hm_push(",hashmap_ptr_type," ptr, ",key_type,"* k, ",value_type,"* v);\n"
	);
	tstring* hashmap_get_decl = tstring_n_compose("tctctctc",
		accessor_type, " ", prefix, "_hm_get(",hashmap_ptr_type," ptr, ",key_type,"* k);\n"
	);
	tstring* hashmap_endget_decl = tstring_n_compose("ctctc",
		"void ", prefix, "_hm_endget(",accessor_type," acc);\n"
	);
	tstring* hashmap_remove_decl = tstring_n_compose("ctctctc",
		"void ", prefix, "_hm_remove(",hashmap_ptr_type," ptr, ",key_type,"* k);\n"
	);

	tstring* top_guard = tstring_n_compose("ctctc",
		"#ifndef GUARD_", prefix,
		"\n#define GUARD_", prefix,"\n\n"
	);
	tstring* bottom_guard = tstring_n_compose("ctc",
		"\n#endif // GUARD_", prefix, "\n"
	);
	tstring* extc_top_guard = cstring_to_tstring(
		"#ifdef __cplusplus\n"
		"extern \"C\" {\n"
		"#endif\n"
	);
	tstring* extc_bottom_guard = cstring_to_tstring(
		"#ifdef __cplusplus\n"
		"}\n"
		"#endif\n"
	);
	tstring* cpp_header_include = cstring_to_tstring(
		"#include \"lfhmap.hpp\"\n"
	);
	tstring* key_equality_predicate_handler = tstring_n_compose("ctctctctc",
		"bool operator==(",key_type,"& lhs,",key_type,"& rhs) {\n"
		"	return K_comp_pred((void*)&lhs,(void*)&rhs);\n"
		"}\n"
		"bool operator!=(",key_type,"& lhs,",key_type,"& rhs) {\n"
		"	return !K_comp_pred((void*)&lhs,(void*)&rhs);\n"
		"}\n"
	);
	tstring* to_cpp_hashmap_cast = tstring_n_compose("ctc",
		"(", cpp_hashmap_ptr_type, ")"
	);
	tstring* from_cpp_hashmap_cast = tstring_n_compose("ctc",
		"(", hashmap_ptr_type, ")"
	);

	tstring* create_hashmap_impl = tstring_n_compose("tctctctc",
		hashmap_ptr_type," ",prefix,"_hm_create(){\n"
		"	return ",from_cpp_hashmap_cast,"new ",cpp_hashmap_type,"();\n"
		"}\n"
	);
	tstring* destroy_hashmap_impl = tstring_n_compose("ctctctc",
		"void ", prefix, "_hm_destroy(",hashmap_ptr_type," value){\n"
		"	delete ",to_cpp_hashmap_cast,"value;\n"
		"}\n"
	);

	tstring* hashmap_push_impl = tstring_n_compose("ctctctctctc",
		"void ", prefix, "_hm_push(",hashmap_ptr_type," ptr, ",key_type,"* k, ",value_type,"* v){\n"
		"	(",to_cpp_hashmap_cast,"ptr)->set(*k, *v);\n"
		"}\n"
	);
	tstring* hashmap_get_impl = tstring_n_compose("tctctctctctctc",
		accessor_type, " ", prefix, "_hm_get(",hashmap_ptr_type," ptr, ",key_type,"* k){\n",
			accessor_type, " acc;\n"
		"	auto obtained = (",to_cpp_hashmap_cast,"ptr)->get(*k);\n"
		"	if(obtained) {\n"
		"		acc.value = (void*)new mct20::accessor<",value_type,">(obtained.value());\n"
		"	} else {\n"
		"		acc.value = nullptr;\n"
		"	}\n"
		"}\n"
	);
	tstring* hashmap_endget_impl = tstring_n_compose("ctctctc",
		"void ", prefix, "_hm_endget(",accessor_type," acc) {\n"
		"	delete (mct20::accessor<",value_type,">*)acc.value;\n"
		"}\n"
	);
	tstring* hashmap_remove_impl = tstring_n_compose("ctctctctc",
		"void ", prefix, "_hm_remove(",hashmap_ptr_type," ptr, ",key_type,"* k) {\n"
		"	(",to_cpp_hashmap_cast,"ptr)->remove(*k);\n"
		"}\n"
	);

	{
		FILE* header;
		if(
			!(header = fopen(header_filename->data, "w"))
		) {
			char* m = header_filename->data;
			fprintf(stderr, "Couldn't open header file: %s\n", header_filename->data);
			exit(EXIT_FAILURE);
		}
		if(
			tstring_n_write(
				header,14,
				top_guard,
				extc_top_guard,
				key_type_decl,
				value_type_decl,
				accessor_type_decl,
				hashmap_decl,
				create_hashmap_decl,
				destroy_hashmap_decl,
				hashmap_get_decl,
				hashmap_endget_decl,
				hashmap_push_decl,
				hashmap_remove_decl,
				extc_bottom_guard,
				bottom_guard
			) != 0
		) {
			fprintf(stderr, "Couldn't generate header file: error writing to file: %s\n", header_filename->data);
			exit(EXIT_FAILURE);
		}
		fclose(header);
	}
	{
		FILE* source;
		if(
			!(source = fopen(source_filename->data, "w"))
		) {
			char* m = source_filename->data;
			fprintf(stderr, "Couldn't open source file: %s\n", source_filename->data);
			exit(EXIT_FAILURE);
		}
		if(
			tstring_n_write(
				source,22,
				top_guard,
				cpp_header_include,
				extc_top_guard,
				key_type_decl,
				value_type_decl,
				accessor_type_decl,
				hash_decl,
				hashmap_decl,

				create_hashmap_decl,
				destroy_hashmap_decl,
				hashmap_get_decl,
				hashmap_endget_decl,
				hashmap_push_decl,
				hashmap_remove_decl,

				create_hashmap_impl,
				destroy_hashmap_impl,
				hashmap_get_impl,
				hashmap_endget_impl,
				hashmap_push_impl,
				hashmap_remove_impl,
				extc_bottom_guard,
				bottom_guard
			) != 0
		) {
			fprintf(stderr, "Couldn't generate header file: error writing to file: %s\n", source_filename->data);
			exit(EXIT_FAILURE);
		}
		fclose(source);
	}
}