Make struct pointer loading language-specific and reliable for TS
[ldk-java] / typescript_strings.py
1 from bindingstypes import ConvInfo
2 from enum import Enum
3
4 def first_to_lower(string: str) -> str:
5     first = string[0]
6     return first.lower() + string[1:]
7
8
9 class Target(Enum):
10     NODEJS = 1,
11     BROWSER = 2
12
13 class Consts:
14     def __init__(self, DEBUG: bool, target: Target, outdir: str, **kwargs):
15         self.outdir = outdir
16         self.struct_file_suffixes = {}
17         self.c_type_map = dict(
18             uint8_t = ['number', 'Uint8Array'],
19             uint16_t = ['number', 'Uint16Array'],
20             uint32_t = ['number', 'Uint32Array'],
21             uint64_t = ['number'],
22         )
23
24         self.wasm_decoding_map = dict(
25             int8_tArray = 'decodeUint8Array'
26         )
27
28         self.wasm_encoding_map = dict(
29             int8_tArray = 'encodeUint8Array',
30         )
31
32         self.to_hu_conv_templates = dict(
33             ptr = 'const {var_name}_hu_conv: {human_type} = new {human_type}(null, {var_name});',
34             default = 'const {var_name}_hu_conv: {human_type} = new {human_type}(null, {var_name});',
35         )
36
37         self.bindings_header = self.wasm_import_header(target) + """
38 export class VecOrSliceDef {
39     public dataptr: number;
40     public datalen: number;
41     public stride: number;
42     public constructor(dataptr: number, datalen: number, stride: number) {
43         this.dataptr = dataptr;
44         this.datalen = datalen;
45         this.stride = stride;
46     }
47 }
48
49 /*
50 TODO: load WASM file
51 static {
52     System.loadLibrary(\"lightningjni\");
53     init(java.lang.Enum.class, VecOrSliceDef.class);
54     init_class_cache();
55 }
56
57 static native void init(java.lang.Class c, java.lang.Class slicedef);
58 static native void init_class_cache();
59
60 public static native boolean deref_bool(long ptr);
61 public static native long deref_long(long ptr);
62 public static native void free_heap_ptr(long ptr);
63 public static native byte[] read_bytes(long ptr, long len);
64 public static native byte[] get_u8_slice_bytes(long slice_ptr);
65 public static native long bytes_to_u8_vec(byte[] bytes);
66 public static native long new_txpointer_copy_data(byte[] txdata);
67 public static native void txpointer_free(long ptr);
68 public static native byte[] txpointer_get_buffer(long ptr);
69 public static native long vec_slice_len(long vec);
70 public static native long new_empty_slice_vec();
71 */
72
73 """
74
75         self.bindings_version_file = ""
76
77         self.bindings_footer = ""
78
79         self.util_fn_pfx = ""
80         self.util_fn_sfx = ""
81
82         self.common_base = """
83 function freer(f: () => void) { f() }
84 const finalizer = new FinalizationRegistry(freer);
85 function get_freeer(ptr: number, free_fn: (number) => void) {
86         return () => {
87                 free_fn(ptr);
88         }
89 }
90
91 export default class CommonBase {
92         protected ptr: number;
93         protected ptrs_to: object[] = [];
94         protected constructor(ptr: number, free_fn: (ptr: number) => void) {
95                 this.ptr = ptr;
96                 if (Number.isFinite(ptr) && ptr != 0){
97                         finalizer.register(this, get_freeer(ptr, free_fn));
98                 }
99         }
100         // In Java, protected means "any subclass can access fields on any other subclass'"
101         // In TypeScript, protected means "any subclass can access parent fields on instances of itself"
102         // To work around this, we add accessors for other instances' protected fields here.
103         protected static add_ref_from(holder: CommonBase, referent: object) {
104                 holder.ptrs_to.push(referent);
105         }
106         protected static get_ptr_of(o: CommonBase) {
107                 return o.ptr;
108         }
109         protected static set_null_skip_free(o: CommonBase) {
110                 o.ptr = 0;
111                 finalizer.unregister(o);
112         }
113 }
114 """
115
116         self.c_file_pfx = """#include "js-wasm.h"
117 #include <stdatomic.h>
118 #include <lightning.h>
119
120 // These should be provided...somehow...
121 void *memset(void *s, int c, size_t n);
122 void *memcpy(void *dest, const void *src, size_t n);
123 int memcmp(const void *s1, const void *s2, size_t n);
124
125 void __attribute__((noreturn)) abort(void);
126 static inline void assert(bool expression) {
127         if (!expression) { abort(); }
128 }
129 """
130
131         if not DEBUG:
132             self.c_file_pfx = self.c_file_pfx + """
133 void *malloc(size_t size);
134 void free(void *ptr);
135
136 #define MALLOC(a, _) malloc(a)
137 #define FREE(p) if ((unsigned long)(p) > 4096) { free(p); }
138 #define DO_ASSERT(a) (void)(a)
139 #define CHECK(a)
140 #define CHECK_ACCESS(p)
141 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v)
142 """
143         else:
144             self.c_file_pfx = self.c_file_pfx + """
145 // Always run a, then assert it is true:
146 #define DO_ASSERT(a) do { bool _assert_val = (a); assert(_assert_val); } while(0)
147 // Assert a is true or do nothing
148 #define CHECK(a) DO_ASSERT(a)
149
150 // Running a leak check across all the allocations and frees of the JDK is a mess,
151 // so instead we implement our own naive leak checker here, relying on the -wrap
152 // linker option to wrap malloc/calloc/realloc/free, tracking everyhing allocated
153 // and free'd in Rust or C across the generated bindings shared library.
154
155 #define BT_MAX 128
156 typedef struct allocation {
157         struct allocation* next;
158         void* ptr;
159         const char* struct_name;
160 } allocation;
161 static allocation* allocation_ll = NULL;
162
163 void* __real_malloc(size_t len);
164 void* __real_calloc(size_t nmemb, size_t len);
165 static void new_allocation(void* res, const char* struct_name) {
166         allocation* new_alloc = __real_malloc(sizeof(allocation));
167         new_alloc->ptr = res;
168         new_alloc->struct_name = struct_name;
169         new_alloc->next = allocation_ll;
170         allocation_ll = new_alloc;
171 }
172 static void* MALLOC(size_t len, const char* struct_name) {
173         void* res = __real_malloc(len);
174         new_allocation(res, struct_name);
175         return res;
176 }
177 void __real_free(void* ptr);
178 static void alloc_freed(void* ptr) {
179         allocation* p = NULL;
180         allocation* it = allocation_ll;
181         while (it->ptr != ptr) {
182                 p = it; it = it->next;
183                 if (it == NULL) {
184                         //XXX: fprintf(stderr, "Tried to free unknown pointer %p\\n", ptr);
185                         return; // addrsan should catch malloc-unknown and print more info than we have
186                 }
187         }
188         if (p) { p->next = it->next; } else { allocation_ll = it->next; }
189         DO_ASSERT(it->ptr == ptr);
190         __real_free(it);
191 }
192 static void FREE(void* ptr) {
193         if ((unsigned long)ptr <= 4096) return; // Rust loves to create pointers to the NULL page for dummys
194         alloc_freed(ptr);
195         __real_free(ptr);
196 }
197
198 static void CHECK_ACCESS(const void* ptr) {
199         allocation* it = allocation_ll;
200         while (it->ptr != ptr) {
201                 it = it->next;
202                 if (it == NULL) {
203                         return; // addrsan should catch malloc-unknown and print more info than we have
204                 }
205         }
206 }
207 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v) \\
208         if (v.is_owned && v.inner != NULL) { \\
209                 const void *p = __unmangle_inner_ptr(v.inner); \\
210                 if (p != NULL) { \\
211                         CHECK_ACCESS(p); \\
212                 } \\
213         }
214
215 void* __wrap_malloc(size_t len) {
216         void* res = __real_malloc(len);
217         new_allocation(res, "malloc call");
218         return res;
219 }
220 void* __wrap_calloc(size_t nmemb, size_t len) {
221         void* res = __real_calloc(nmemb, len);
222         new_allocation(res, "calloc call");
223         return res;
224 }
225 void __wrap_free(void* ptr) {
226         if (ptr == NULL) return;
227         alloc_freed(ptr);
228         __real_free(ptr);
229 }
230
231 void* __real_realloc(void* ptr, size_t newlen);
232 void* __wrap_realloc(void* ptr, size_t len) {
233         if (ptr != NULL) alloc_freed(ptr);
234         void* res = __real_realloc(ptr, len);
235         new_allocation(res, "realloc call");
236         return res;
237 }
238 void __wrap_reallocarray(void* ptr, size_t new_sz) {
239         // Rust doesn't seem to use reallocarray currently
240         DO_ASSERT(false);
241 }
242
243 void __attribute__((destructor)) check_leaks() {
244         for (allocation* a = allocation_ll; a != NULL; a = a->next) {
245                 //XXX: fprintf(stderr, "%s %p remains\\n", a->struct_name, a->ptr);
246         }
247         DO_ASSERT(allocation_ll == NULL);
248 }
249 """
250         self.c_file_pfx = self.c_file_pfx + """
251 // We assume that CVec_u8Z and u8slice are the same size and layout (and thus pointers to the two can be mixed)
252 _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKu8slice), "Vec<u8> and [u8] need to have been mapped identically");
253 _Static_assert(offsetof(LDKCVec_u8Z, data) == offsetof(LDKu8slice, data), "Vec<u8> and [u8] need to have been mapped identically");
254 _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKu8slice, datalen), "Vec<u8> and [u8] need to have been mapped identically");
255
256 _Static_assert(sizeof(void*) == 4, "Pointers mut be 32 bits");
257
258 #define DECL_ARR_TYPE(ty, name) \\
259         struct name##array { \\
260                 uint32_t arr_len; \\
261                 ty elems[]; \\
262         }; \\
263         typedef struct name##array * name##Array; \\
264         static inline name##Array init_##name##Array(size_t arr_len) { \\
265                 name##Array arr = (name##Array)MALLOC(arr_len * sizeof(ty) + sizeof(uint32_t), "##name array init"); \\
266                 arr->arr_len = arr_len; \\
267                 return arr; \\
268         }
269
270 DECL_ARR_TYPE(int64_t, int64_t);
271 DECL_ARR_TYPE(int8_t, int8_t);
272 DECL_ARR_TYPE(uint32_t, uint32_t);
273 DECL_ARR_TYPE(void*, ptr);
274 DECL_ARR_TYPE(char, char);
275 typedef charArray jstring;
276
277 static inline jstring str_ref_to_ts(const char* chars, size_t len) {
278         charArray arr = init_charArray(len);
279         memcpy(arr->elems, chars, len);
280         return arr;
281 }
282 static inline LDKStr str_ref_to_owned_c(const jstring str) {
283         char* newchars = MALLOC(str->arr_len + 1, "String chars");
284         memcpy(newchars, str->elems, str->arr_len);
285         newchars[str->arr_len] = 0;
286         LDKStr res = {
287                 .chars = newchars,
288                 .len = str->arr_len,
289                 .chars_is_owned = true
290         };
291         return res;
292 }
293
294 typedef bool jboolean;
295
296 uint32_t __attribute__((visibility("default"))) TS_malloc(uint32_t size) {
297         return (uint32_t)MALLOC(size, "JS-Called malloc");
298 }
299 void __attribute__((visibility("default"))) TS_free(uint32_t ptr) {
300         FREE((void*)ptr);
301 }
302 """
303
304         self.c_version_file = ""
305
306         self.hu_struct_file_prefix = """
307 import CommonBase from './CommonBase.mjs';
308 import * as bindings from '../bindings.mjs'
309 import * as InternalUtils from '../InternalUtils.mjs'
310
311 """
312         self.c_fn_ty_pfx = ""
313         self.file_ext = ".mts"
314         self.ptr_c_ty = "uint32_t"
315         self.ptr_native_ty = "number"
316         self.result_c_ty = "uint32_t"
317         self.ptr_arr = "ptrArray"
318         self.is_arr_some_check = ("", " != 0")
319         self.get_native_arr_len_call = ("", "->arr_len")
320
321         with open(outdir + "/InternalUtils.mts", "w") as f:
322             f.write("export function check_arr_len(arr: Uint8Array, len: number): Uint8Array {\n")
323             f.write("\tif (arr.length != len) { throw new Error(\"Expected array of length \" + len + \"got \" + arr.length); }\n")
324             f.write("\treturn arr;\n")
325             f.write("}")
326
327     def release_native_arr_ptr_call(self, ty_info, arr_var, arr_ptr_var):
328         return None
329     def create_native_arr_call(self, arr_len, ty_info):
330         if ty_info.c_ty == "ptrArray":
331             assert ty_info.subty is not None and ty_info.subty.c_ty.endswith("Array")
332         return "init_" + ty_info.c_ty + "(" + arr_len + ")"
333     def set_native_arr_contents(self, arr_name, arr_len, ty_info):
334         if ty_info.c_ty == "int8_tArray":
335             return ("memcpy(" + arr_name + "->elems, ", ", " + arr_len + ")")
336         else:
337             assert False
338     def get_native_arr_contents(self, arr_name, dest_name, arr_len, ty_info, copy):
339         if ty_info.c_ty == "int8_tArray":
340             if copy:
341                 return "memcpy(" + dest_name + ", " + arr_name + "->elems, " + arr_len + ")"
342         if ty_info.c_ty == "ptrArray":
343             return "(void*) " + arr_name + "->elems"
344         else:
345             assert not copy
346             return arr_name + "->elems"
347     def get_native_arr_elem(self, arr_name, idxc, ty_info):
348         assert False # Only called if above is None
349     def get_native_arr_ptr_call(self, ty_info):
350         if ty_info.subty is not None:
351             return "(" + ty_info.subty.c_ty + "*)(", " + 4)"
352         return "(" + ty_info.c_ty + "*)(", " + 4)"
353     def get_native_arr_entry_call(self, ty_info, arr_name, idxc, entry_access):
354         return None
355     def cleanup_native_arr_ref_contents(self, arr_name, dest_name, arr_len, ty_info):
356         if ty_info.c_ty == "int8_tArray":
357             return None
358         else:
359             return None
360
361     def str_ref_to_native_call(self, var_name, str_len):
362         return "str_ref_to_ts(" + var_name + ", " + str_len + ")"
363     def str_ref_to_c_call(self, var_name):
364         return "str_ref_to_owned_c(" + var_name + ")"
365
366     def c_fn_name_define_pfx(self, fn_name, have_args):
367         return " __attribute__((visibility(\"default\"))) TS_" + fn_name + "("
368
369     def wasm_import_header(self, target):
370         res = """
371 const memory = new WebAssembly.Memory({initial: 256});
372
373 const imports: any = {};
374 imports.env = {};
375
376 imports.env.memoryBase = 0;
377 imports.env.memory = memory;
378 imports.env.tableBase = 0;
379 imports.env.table = new WebAssembly.Table({initial: 4, element: 'anyfunc'});
380
381 imports.env["abort"] = function () {
382         console.error("ABORT");
383 };
384 imports.env["js_invoke_function"] = function(fn: number, arg1: number, arg2: number, arg3: number, arg4: number, arg5: number, arg6: number, arg7: number, arg8: number, arg9: number, arg10: number) {
385         console.log('function called from wasm:', fn, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9, arg10);
386 };
387 imports.env["js_free_function_ptr"] = function(fn: number) {
388         console.log("function ptr free'd from wasm:", fn);
389 };
390
391 imports.wasi_snapshot_preview1 = {
392         "fd_write" : () => {
393                 console.log("ABORT");
394         },
395         "random_get" : () => {
396                 console.log("RAND GET");
397         },
398         "environ_sizes_get" : () => {
399                 console.log("wasi_snapshot_preview1:environ_sizes_get");
400         },
401         "proc_exit" : () => {
402                 console.log("wasi_snapshot_preview1:proc_exit");
403         },
404         "environ_get" : () => {
405                 console.log("wasi_snapshot_preview1:environ_get");
406         },
407 };
408
409 var wasm = null;
410 let isWasmInitialized: boolean = false;
411 """
412
413         if target == Target.NODEJS:
414             res += """import * as fs from 'fs';
415 export async function initializeWasm(path) {
416         const source = fs.readFileSync(path);
417         const { instance: wasmInstance } = await WebAssembly.instantiate(source, imports);
418         wasm = wasmInstance.exports;
419         isWasmInitialized = true;
420 };
421 """
422         else:
423             res += """
424 export async function initializeWasm(uri) {
425         const stream = fetch(uri);
426         const { instance: wasmInstance } = await WebAssembly.instantiateStreaming(stream, imports);
427         wasm = wasmInstance.exports;
428         isWasmInitialized = true;
429 };
430
431 """
432
433         return res + """
434
435
436 // WASM CODEC
437
438 const nextMultipleOfFour = (value: number) => {
439         return Math.ceil(value / 4) * 4;
440 }
441
442 const encodeUint8Array = (inputArray) => {
443         const cArrayPointer = wasm.TS_malloc(inputArray.length + 4);
444         const arrayLengthView = new Uint32Array(memory.buffer, cArrayPointer, 1);
445         arrayLengthView[0] = inputArray.length;
446         const arrayMemoryView = new Uint8Array(memory.buffer, cArrayPointer + 4, inputArray.length);
447         arrayMemoryView.set(inputArray);
448         return cArrayPointer;
449 }
450
451 const encodeUint32Array = (inputArray) => {
452         const cArrayPointer = wasm.TS_malloc((inputArray.length + 1) * 4);
453         const arrayMemoryView = new Uint32Array(memory.buffer, cArrayPointer, inputArray.length);
454         arrayMemoryView.set(inputArray, 1);
455         arrayMemoryView[0] = inputArray.length;
456         return cArrayPointer;
457 }
458
459 const getArrayLength = (arrayPointer) => {
460         const arraySizeViewer = new Uint32Array(
461                 memory.buffer, // value
462                 arrayPointer, // offset
463                 1 // one int
464         );
465         return arraySizeViewer[0];
466 }
467 const decodeUint8Array = (arrayPointer, free = true) => {
468         const arraySize = getArrayLength(arrayPointer);
469         const actualArrayViewer = new Uint8Array(
470                 memory.buffer, // value
471                 arrayPointer + 4, // offset (ignoring length bytes)
472                 arraySize // uint8 count
473         );
474         // Clone the contents, TODO: In the future we should wrap the Viewer in a class that
475         // will free the underlying memory when it becomes unreachable instead of copying here.
476         const actualArray = actualArrayViewer.slice(0, arraySize);
477         if (free) {
478                 wasm.TS_free(arrayPointer);
479         }
480         return actualArray;
481 }
482 const decodeUint32Array = (arrayPointer, free = true) => {
483         const arraySize = getArrayLength(arrayPointer);
484         const actualArrayViewer = new Uint32Array(
485                 memory.buffer, // value
486                 arrayPointer + 4, // offset (ignoring length bytes)
487                 arraySize // uint32 count
488         );
489         // Clone the contents, TODO: In the future we should wrap the Viewer in a class that
490         // will free the underlying memory when it becomes unreachable instead of copying here.
491         const actualArray = actualArrayViewer.slice(0, arraySize);
492         if (free) {
493                 wasm.TS_free(arrayPointer);
494         }
495         return actualArray;
496 }
497
498 const encodeString = (string) => {
499         // make malloc count divisible by 4
500         const memoryNeed = nextMultipleOfFour(string.length + 1);
501         const stringPointer = wasm.TS_malloc(memoryNeed);
502         const stringMemoryView = new Uint8Array(
503                 memory.buffer, // value
504                 stringPointer, // offset
505                 string.length + 1 // length
506         );
507         for (let i = 0; i < string.length; i++) {
508                 stringMemoryView[i] = string.charCodeAt(i);
509         }
510         stringMemoryView[string.length] = 0;
511         return stringPointer;
512 }
513
514 const decodeString = (stringPointer, free = true) => {
515         const memoryView = new Uint8Array(memory.buffer, stringPointer);
516         let cursor = 0;
517         let result = '';
518
519         while (memoryView[cursor] !== 0) {
520                 result += String.fromCharCode(memoryView[cursor]);
521                 cursor++;
522         }
523
524         if (free) {
525                 wasm.wasm_free(stringPointer);
526         }
527
528         return result;
529 };
530 """
531
532     def init_str(self):
533         return ""
534
535     def var_decl_statement(self, ty_string, var_name, statement):
536         return "const " + var_name + ": " + ty_string + " = " + statement
537
538     def get_ptr(self, var):
539         return "CommonBase.get_ptr_of(" + var + ")"
540     def set_null_skip_free(self, var):
541         return "CommonBase.set_null_skip_free(" + var + ");"
542
543     def add_ref(self, holder, referent):
544         return "CommonBase.add_ref_from(" + holder + ", " + referent + ")"
545
546     def obj_defined(self, struct_names, folder):
547         with open(self.outdir + "/index.mts", 'a') as index:
548             index.write(f"export * from './{folder}/{struct_names[0]}.mjs';\n")
549         with open(self.outdir + "/imports.mts.part", 'a') as imports:
550             imports.write(f"import {{ {', '.join(struct_names)} }} from '../{folder}/{struct_names[0]}.mjs';\n")
551
552     def native_c_unitary_enum_map(self, struct_name, variants, enum_doc_comment):
553         out_c = "static inline LDK" + struct_name + " LDK" + struct_name + "_from_js(int32_t ord) {\n"
554         out_c = out_c + "\tswitch (ord) {\n"
555         ord_v = 0
556
557         out_typescript_enum_fields = ""
558
559         for var, var_docs in variants:
560             out_c = out_c + "\t\tcase %d: return %s;\n" % (ord_v, var)
561             ord_v = ord_v + 1
562             if var_docs is not None:
563                 out_typescript_enum_fields += f"/**\n * {var_docs}\n */\n"
564             out_typescript_enum_fields += f"{var},\n\t\t\t\t"
565         out_c = out_c + "\t}\n"
566         out_c = out_c + "\tabort();\n"
567         out_c = out_c + "}\n"
568
569         out_c = out_c + "static inline int32_t LDK" + struct_name + "_to_js(LDK" + struct_name + " val) {\n"
570         out_c = out_c + "\tswitch (val) {\n"
571         ord_v = 0
572         for var, _ in variants:
573             out_c = out_c + "\t\tcase " + var + ": return %d;\n" % ord_v
574             ord_v = ord_v + 1
575         out_c = out_c + "\t\tdefault: abort();\n"
576         out_c = out_c + "\t}\n"
577         out_c = out_c + "}\n"
578
579         out_typescript = f"""
580             export enum {struct_name} {{
581                 {out_typescript_enum_fields}
582             }}
583 """
584         out_typescript_enum = f"export {{ {struct_name} }} from \"../bindings.mjs\";"
585         self.obj_defined([struct_name], "enums")
586         return (out_c, out_typescript_enum, out_typescript)
587
588     def c_unitary_enum_to_native_call(self, ty_info):
589         return (ty_info.rust_obj + "_to_js(", ")")
590     def native_unitary_enum_to_c_call(self, ty_info):
591         return (ty_info.rust_obj + "_from_js(", ")")
592
593     def c_complex_enum_pass_ty(self, struct_name):
594         return "uint32_t"
595
596     def c_constr_native_complex_enum(self, struct_name, variant, c_params):
597         ret = "0 /* " + struct_name + " - " + variant + " */"
598         for param in c_params:
599             ret = ret + "; (void) " + param
600         return ret
601
602     def native_c_map_trait(self, struct_name, field_var_conversions, flattened_field_var_conversions, field_function_lines, trait_doc_comment):
603         out_typescript_bindings = "\n\n\n// OUT_TYPESCRIPT_BINDINGS :: MAP_TRAIT :: START\n\n"
604
605         constructor_arguments = ""
606         super_instantiator = ""
607         pointer_to_adder = ""
608         impl_constructor_arguments = ""
609         for var in flattened_field_var_conversions:
610             if isinstance(var, ConvInfo):
611                 constructor_arguments += f", {first_to_lower(var.arg_name)}?: {var.java_hu_ty}"
612                 impl_constructor_arguments += f", {var.arg_name}: {var.java_hu_ty}"
613                 if var.from_hu_conv is not None:
614                     super_instantiator += ", " + var.from_hu_conv[0]
615                     if var.from_hu_conv[1] != "":
616                         pointer_to_adder += var.from_hu_conv[1] + ";\n"
617                 else:
618                     super_instantiator += ", " + first_to_lower(var.arg_name)
619             else:
620                 constructor_arguments += f", {first_to_lower(var[1])}?: bindings.{var[0]}"
621                 super_instantiator += ", " + first_to_lower(var[1])
622                 pointer_to_adder += "this.ptrs_to.push(" + first_to_lower(var[1]) + ");\n"
623                 impl_constructor_arguments += f", {first_to_lower(var[1])}_impl: {var[0].replace('LDK', '')}.{var[0].replace('LDK', '')}Interface"
624
625         # BUILD INTERFACE METHODS
626         out_java_interface = ""
627         out_interface_implementation_overrides = ""
628         java_methods = []
629         for fn_line in field_function_lines:
630             java_method_descriptor = ""
631             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
632                 out_java_interface += fn_line.fn_name + "("
633                 out_interface_implementation_overrides += f"{fn_line.fn_name} ("
634
635                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
636                     if idx >= 1:
637                         out_java_interface += ", "
638                         out_interface_implementation_overrides += ", "
639                     out_java_interface += f"{arg_conv_info.arg_name}: {arg_conv_info.java_hu_ty}"
640                     out_interface_implementation_overrides += f"{arg_conv_info.arg_name}: {arg_conv_info.java_ty}"
641                     java_method_descriptor += arg_conv_info.java_fn_ty_arg
642                 out_java_interface += f"): {fn_line.ret_ty_info.java_hu_ty};\n\t\t\t\t"
643                 java_method_descriptor += ")" + fn_line.ret_ty_info.java_fn_ty_arg
644                 java_methods.append((fn_line.fn_name, java_method_descriptor))
645
646                 out_interface_implementation_overrides += f"): {fn_line.ret_ty_info.java_ty} {{\n"
647
648                 interface_method_override_inset = "\t\t\t\t\t\t"
649                 interface_implementation_inset = "\t\t\t\t\t\t\t"
650                 for arg_info in fn_line.args_ty:
651                     if arg_info.to_hu_conv is not None:
652                         out_interface_implementation_overrides += interface_implementation_inset + arg_info.to_hu_conv.replace("\n", "\n\t\t\t\t") + "\n"
653
654                 if fn_line.ret_ty_info.java_ty != "void":
655                     out_interface_implementation_overrides += interface_implementation_inset + fn_line.ret_ty_info.java_hu_ty + " ret = arg." + fn_line.fn_name + "("
656                 else:
657                     out_interface_implementation_overrides += f"{interface_implementation_inset}arg." + fn_line.fn_name + "("
658
659                 for idx, arg_info in enumerate(fn_line.args_ty):
660                     if idx != 0:
661                         out_interface_implementation_overrides += ", "
662                     if arg_info.to_hu_conv_name is not None:
663                         out_interface_implementation_overrides += arg_info.to_hu_conv_name
664                     else:
665                         out_interface_implementation_overrides += arg_info.arg_name
666
667                 out_interface_implementation_overrides += ");\n"
668                 if fn_line.ret_ty_info.java_ty != "void":
669                     if fn_line.ret_ty_info.from_hu_conv is not None:
670                         out_interface_implementation_overrides = out_interface_implementation_overrides + "\t\t\t\t" + f"result: {fn_line.ret_ty_info.java_ty} = " + fn_line.ret_ty_info.from_hu_conv[0] + ";\n"
671                         if fn_line.ret_ty_info.from_hu_conv[1] != "":
672                             out_interface_implementation_overrides = out_interface_implementation_overrides + "\t\t\t\t" + fn_line.ret_ty_info.from_hu_conv[1].replace("this", "impl_holder.held") + ";\n"
673                         #if fn_line.ret_ty_info.rust_obj in result_types:
674                         # XXX: We need to handle this in conversion logic so that its cross-language!
675                         # Avoid double-free by breaking the result - we should learn to clone these and then we can be safe instead
676                         #    out_interface_implementation_overrides = out_interface_implementation_overrides + "\t\t\t\tret.ptr = 0;\n"
677                         out_interface_implementation_overrides = out_interface_implementation_overrides + "\t\t\t\treturn result;\n"
678                     else:
679                         out_interface_implementation_overrides = out_interface_implementation_overrides + "\t\t\t\treturn ret;\n"
680                 out_interface_implementation_overrides += f"{interface_method_override_inset}}},\n\n{interface_method_override_inset}"
681
682         trait_constructor_arguments = ""
683         for var in field_var_conversions:
684             if isinstance(var, ConvInfo):
685                 trait_constructor_arguments += ", " + var.arg_name
686             else:
687                 trait_constructor_arguments += ", " + var[1] + ".new_impl(" + var[1] + "_impl"
688                 for suparg in var[2]:
689                     if isinstance(suparg, ConvInfo):
690                         trait_constructor_arguments += ", " + suparg.arg_name
691                     else:
692                         trait_constructor_arguments += ", " + suparg[1]
693                 trait_constructor_arguments += ").bindings_instance"
694                 for suparg in var[2]:
695                     if isinstance(suparg, ConvInfo):
696                         trait_constructor_arguments += ", " + suparg.arg_name
697                     else:
698                         trait_constructor_arguments += ", " + suparg[1]
699
700         out_typescript_human = f"""
701 {self.hu_struct_file_prefix}
702
703 {struct_name.replace("LDK","")} extends CommonBase {{
704
705         bindings_instance?: bindings.{struct_name};
706
707         constructor(ptr?: number, arg?: bindings.{struct_name}{constructor_arguments}) {{
708                 if (Number.isFinite(ptr)) {{
709                         super(ptr, bindings.{struct_name.replace("LDK","")}_free);
710                         this.bindings_instance = null;
711                 }} else {{
712                         // TODO: private constructor instantiation
713                         super(bindings.{struct_name}_new(arg{super_instantiator}));
714                         this.ptrs_to.push(arg);
715                         {pointer_to_adder}
716                 }}
717         }}
718
719         static new_impl(arg: {struct_name.replace("LDK", "")}Interface{impl_constructor_arguments}): {struct_name.replace("LDK", "")} {{
720                 const impl_holder: {struct_name}Holder = new {struct_name}Holder();
721                 let structImplementation = <bindings.{struct_name}>{{
722                         // todo: in-line interface filling
723                         {out_interface_implementation_overrides}
724                 }};
725                 impl_holder.held = new {struct_name.replace("LDK", "")} (null, structImplementation{trait_constructor_arguments});
726         }}
727
728         export interface {struct_name.replace("LDK", "")}Interface {{
729                 {out_java_interface}
730         }}
731
732         class {struct_name}Holder {{
733                 held: {struct_name.replace("LDK", "")};
734         }}
735 """
736
737         out_typescript_bindings += "\t\texport interface " + struct_name + " {\n"
738         java_meths = []
739         for fn_line in field_function_lines:
740             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
741                 out_typescript_bindings += f"\t\t\t{fn_line.fn_name} ("
742
743                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
744                     if idx >= 1:
745                         out_typescript_bindings = out_typescript_bindings + ", "
746                     out_typescript_bindings += f"{arg_conv_info.arg_name}: {arg_conv_info.java_ty}"
747
748                 out_typescript_bindings += f"): {fn_line.ret_ty_info.java_ty};\n"
749
750         out_typescript_bindings = out_typescript_bindings + "\t\t}\n\n"
751
752         out_typescript_bindings += f"\t\texport function {struct_name}_new(impl: {struct_name}"
753         for var in flattened_field_var_conversions:
754             if isinstance(var, ConvInfo):
755                 out_typescript_bindings += f", {var.arg_name}: {var.java_ty}"
756             else:
757                 out_typescript_bindings += f", {var[1]}: {var[0]}"
758
759         out_typescript_bindings += f"""): number {{
760             throw new Error('unimplemented'); // TODO: bind to WASM
761         }}
762 """
763
764         out_typescript_bindings += '\n// OUT_TYPESCRIPT_BINDINGS :: MAP_TRAIT :: END\n\n\n'
765
766         # Now that we've written out our java code (and created java_meths), generate C
767         out_c = "typedef struct " + struct_name + "_JCalls {\n"
768         out_c = out_c + "\tatomic_size_t refcnt;\n"
769         for var in flattened_field_var_conversions:
770             if isinstance(var, ConvInfo):
771                 # We're a regular ol' field
772                 pass
773             else:
774                 # We're a supertrait
775                 out_c = out_c + "\t" + var[0] + "_JCalls* " + var[1] + ";\n"
776         for fn in field_function_lines:
777             if fn.fn_name != "free" and fn.fn_name != "cloned":
778                 out_c = out_c + "\tuint32_t " + fn.fn_name + "_meth;\n"
779         out_c = out_c + "} " + struct_name + "_JCalls;\n"
780
781         for fn_line in field_function_lines:
782             if fn_line.fn_name == "free":
783                 out_c = out_c + "static void " + struct_name + "_JCalls_free(void* this_arg) {\n"
784                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
785                 out_c = out_c + "\tif (atomic_fetch_sub_explicit(&j_calls->refcnt, 1, memory_order_acquire) == 1) {\n"
786                 for fn in field_function_lines:
787                     if fn.fn_name != "free" and fn.fn_name != "cloned":
788                         out_c = out_c + "\t\tjs_free_function_ptr(j_calls->" + fn.fn_name + "_meth);\n"
789                 out_c = out_c + "\t\tFREE(j_calls);\n"
790                 out_c = out_c + "\t}\n}\n"
791
792         for idx, fn_line in enumerate(field_function_lines):
793             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
794                 assert fn_line.ret_ty_info.ty_info.get_full_rust_ty()[1] == ""
795                 out_c = out_c + fn_line.ret_ty_info.ty_info.get_full_rust_ty()[0] + " " + fn_line.fn_name + "_" + struct_name + "_jcall("
796                 if fn_line.self_is_const:
797                     out_c = out_c + "const void* this_arg"
798                 else:
799                     out_c = out_c + "void* this_arg"
800
801                 for idx, arg in enumerate(fn_line.args_ty):
802                     out_c = out_c + ", " + arg.ty_info.get_full_rust_ty()[0] + " " + arg.arg_name + arg.ty_info.get_full_rust_ty()[1]
803
804                 out_c = out_c + ") {\n"
805                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
806
807                 for arg_info in fn_line.args_ty:
808                     if arg_info.ret_conv is not None:
809                         out_c = out_c + "\t" + arg_info.ret_conv[0].replace('\n', '\n\t')
810                         out_c = out_c + arg_info.arg_name
811                         out_c = out_c + arg_info.ret_conv[1].replace('\n', '\n\t') + "\n"
812
813                 if fn_line.ret_ty_info.c_ty.endswith("Array"):
814                     out_c += "\t" + fn_line.ret_ty_info.c_ty + " ret = (" + fn_line.ret_ty_info.c_ty + ")"
815                     out_c += "js_invoke_function_" + str(len(fn_line.args_ty)) + "(j_calls->" + fn_line.fn_name + "_meth"
816                 elif fn_line.ret_ty_info.java_ty == "void":
817                     out_c = out_c + "\tjs_invoke_function_" + str(len(fn_line.args_ty)) + "(j_calls->" + fn_line.fn_name + "_meth"
818                 elif fn_line.ret_ty_info.java_ty == "String":
819                     out_c = out_c + "\tjstring ret = (jstring)js_invoke_function_" + str(len(fn_line.args_ty)) + "(j_calls->" + fn_line.fn_name + "_meth"
820                 elif not fn_line.ret_ty_info.passed_as_ptr:
821                     out_c = out_c + "\treturn js_invoke_function_" + str(len(fn_line.args_ty)) + "(j_calls->" + fn_line.fn_name + "_meth"
822                 else:
823                     out_c = out_c + "\tuint32_t ret = js_invoke_function_" + str(len(fn_line.args_ty)) + "(j_calls->" + fn_line.fn_name + "_meth"
824
825                 for idx, arg_info in enumerate(fn_line.args_ty):
826                     if arg_info.ret_conv is not None:
827                         out_c = out_c + ", (uint32_t)" + arg_info.ret_conv_name
828                     else:
829                         out_c = out_c + ", (uint32_t)" + arg_info.arg_name
830                 out_c = out_c + ");\n"
831                 if fn_line.ret_ty_info.arg_conv is not None:
832                     out_c = out_c + "\t" + fn_line.ret_ty_info.arg_conv.replace("\n", "\n\t") + "\n\treturn " + fn_line.ret_ty_info.arg_conv_name + ";\n"
833
834                 out_c = out_c + "}\n"
835
836         # Write out a clone function whether we need one or not, as we use them in moving to rust
837         out_c = out_c + "static void " + struct_name + "_JCalls_cloned(" + struct_name + "* new_obj) {\n"
838         out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) new_obj->this_arg;\n"
839         out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->refcnt, 1, memory_order_release);\n"
840         for var in field_var_conversions:
841             if not isinstance(var, ConvInfo):
842                 out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->" + var[1] + "->refcnt, 1, memory_order_release);\n"
843         out_c = out_c + "}\n"
844
845         out_c = out_c + "static inline " + struct_name + " " + struct_name + "_init (/*TODO: JS Object Reference */void* o"
846         for var in flattened_field_var_conversions:
847             if isinstance(var, ConvInfo):
848                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
849             else:
850                 out_c = out_c + ", /*TODO: JS Object Reference */void* " + var[1]
851         out_c = out_c + ") {\n"
852
853         out_c = out_c + "\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n"
854         out_c = out_c + "\tatomic_init(&calls->refcnt, 1);\n"
855         out_c = out_c + "\t//TODO: Assign calls->o from o\n"
856
857         for (fn_name, java_meth_descr) in java_meths:
858             if fn_name != "free" and fn_name != "cloned":
859                 out_c = out_c + "\tcalls->" + fn_name + "_meth = (*env)->GetMethodID(env, c, \"" + fn_name + "\", \"" + java_meth_descr + "\");\n"
860                 out_c = out_c + "\tCHECK(calls->" + fn_name + "_meth != NULL);\n"
861
862         for var in flattened_field_var_conversions:
863             if isinstance(var, ConvInfo) and var.arg_conv is not None:
864                 out_c = out_c + "\n\t" + var.arg_conv.replace("\n", "\n\t") +"\n"
865         out_c = out_c + "\n\t" + struct_name + " ret = {\n"
866         out_c = out_c + "\t\t.this_arg = (void*) calls,\n"
867         for fn_line in field_function_lines:
868             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
869                 out_c = out_c + "\t\t." + fn_line.fn_name + " = " + fn_line.fn_name + "_" + struct_name + "_jcall,\n"
870             elif fn_line.fn_name == "free":
871                 out_c = out_c + "\t\t.free = " + struct_name + "_JCalls_free,\n"
872             else:
873                 out_c = out_c + "\t\t.cloned = " + struct_name + "_JCalls_cloned,\n"
874         for var in field_var_conversions:
875             if isinstance(var, ConvInfo):
876                 if var.arg_conv_name is not None:
877                     out_c = out_c + "\t\t." + var.arg_name + " = " + var.arg_conv_name + ",\n"
878                     out_c = out_c + "\t\t.set_" + var.arg_name + " = NULL,\n"
879                 else:
880                     out_c = out_c + "\t\t." + var.var_name + " = " + var.var_name + ",\n"
881                     out_c = out_c + "\t\t.set_" + var.var_name + " = NULL,\n"
882             else:
883                 out_c += "\t\t." + var[1] + " = " + var[0] + "_init(" + var[1]
884                 for suparg in var[2]:
885                     if isinstance(suparg, ConvInfo):
886                         out_c += ", " + suparg.arg_name
887                     else:
888                         out_c += ", " + suparg[1]
889                 out_c += "),\n"
890         out_c = out_c + "\t};\n"
891         for var in flattened_field_var_conversions:
892             if not isinstance(var, ConvInfo):
893                 out_c = out_c + "\tcalls->" + var[1] + " = ret." + var[1] + ".this_arg;\n"
894         out_c = out_c + "\treturn ret;\n"
895         out_c = out_c + "}\n"
896
897         out_c = out_c + self.c_fn_ty_pfx + "long " + self.c_fn_name_define_pfx(struct_name + "_new", True) + "/*TODO: JS Object Reference */void* o"
898         for var in flattened_field_var_conversions:
899             if isinstance(var, ConvInfo):
900                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
901             else:
902                 out_c = out_c + ", /*TODO: JS Object Reference */ void* " + var[1]
903         out_c = out_c + ") {\n"
904         out_c = out_c + "\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n"
905         out_c = out_c + "\t*res_ptr = " + struct_name + "_init(o"
906         for var in flattened_field_var_conversions:
907             if isinstance(var, ConvInfo):
908                 out_c = out_c + ", " + var.arg_name
909             else:
910                 out_c = out_c + ", " + var[1]
911         out_c = out_c + ");\n"
912         out_c = out_c + "\treturn (long)res_ptr;\n"
913         out_c = out_c + "}\n"
914
915         return (out_typescript_bindings, out_typescript_human, out_c)
916
917     def trait_struct_inc_refcnt(self, ty_info):
918         return ""
919
920     def map_complex_enum(self, struct_name, variant_list, camel_to_snake, enum_doc_comment):
921         bindings_type = struct_name.replace("LDK", "")
922         java_hu_type = struct_name.replace("LDK", "").replace("COption", "Option")
923
924         out_java_enum = ""
925         out_java = ""
926         out_c = ""
927
928         out_java_enum += (self.hu_struct_file_prefix)
929
930         java_hu_class = ""
931         java_hu_class += "export class " + java_hu_type + " extends CommonBase {\n"
932         java_hu_class += "\tprotected constructor(_dummy: object, ptr: number) { super(ptr, bindings." + bindings_type + "_free); }\n"
933         java_hu_class += "\t/* @internal */\n"
934         java_hu_class += f"\tpublic static constr_from_ptr(ptr: number): {java_hu_type} {{\n"
935         java_hu_class += f"\t\tconst raw_val: bindings.{struct_name} = bindings." + struct_name + "_ref_from_ptr(ptr);\n"
936         java_hu_subclasses = ""
937
938         out_java += "\texport class " + struct_name + " {\n"
939         out_java += "\t\tprotected constructor() {}\n"
940         java_subclasses = ""
941         for var in variant_list:
942             java_subclasses += "\texport class " + struct_name + "_" + var.var_name + " extends " + struct_name + " {\n"
943             java_hu_subclasses = java_hu_subclasses + "export class " + java_hu_type + "_" + var.var_name + " extends " + java_hu_type + " {\n"
944             java_hu_class += "\t\tif (raw_val instanceof bindings." + struct_name + "_" + var.var_name + ") {\n"
945             java_hu_class += "\t\t\treturn new " + java_hu_type + "_" + var.var_name + "(ptr, raw_val);\n"
946             init_meth_params = ""
947             hu_conv_body = ""
948             for idx, (field_ty, field_docs) in enumerate(var.fields):
949                 java_hu_subclasses = java_hu_subclasses + "\tpublic " + field_ty.arg_name + f": {field_ty.java_hu_ty};\n"
950                 if field_ty.to_hu_conv is not None:
951                     hu_conv_body = hu_conv_body + "\t\tconst " + field_ty.arg_name + f": {field_ty.java_ty} = obj." + field_ty.arg_name + ";\n"
952                     hu_conv_body = hu_conv_body + "\t\t" + field_ty.to_hu_conv.replace("\n", "\n\t\t\t") + "\n"
953                     hu_conv_body = hu_conv_body + "\t\tthis." + field_ty.arg_name + " = " + field_ty.to_hu_conv_name + ";\n"
954                 else:
955                     hu_conv_body = hu_conv_body + "\t\tthis." + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
956                 if idx > 0:
957                     init_meth_params += ", "
958                 init_meth_params += "public " + field_ty.arg_name + ": " + field_ty.java_ty
959             java_subclasses += "\t\tconstructor(" + init_meth_params + ") { super(); }\n"
960             java_subclasses += "\t}\n"
961             java_hu_class += "\t\t}\n"
962             java_hu_subclasses += "\t/* @internal */\n"
963             java_hu_subclasses += "\tpublic constructor(ptr: number, obj: bindings." + struct_name + "_" + var.var_name + ") {\n\t\tsuper(null, ptr);\n"
964             java_hu_subclasses = java_hu_subclasses + hu_conv_body
965             java_hu_subclasses = java_hu_subclasses + "\t}\n}\n"
966         out_java += ("\t}\n")
967         out_java += java_subclasses
968         java_hu_class += "\t\tthrow new Error('oops, this should be unreachable'); // Unreachable without extending the (internal) bindings interface\n\t}\n\n"
969         out_java += self.fn_call_body(struct_name + "_ref_from_ptr", "uint32_t", "number", "ptr: number", "ptr")
970
971         out_c += (self.c_fn_ty_pfx + self.c_complex_enum_pass_ty(struct_name) + self.c_fn_name_define_pfx(struct_name + "_ref_from_ptr", True) + self.ptr_c_ty + " ptr) {\n")
972         out_c += ("\t" + struct_name + " *obj = (" + struct_name + "*)(ptr & ~1);\n")
973         out_c += ("\tswitch(obj->tag) {\n")
974         for var in variant_list:
975             out_c += ("\t\tcase " + struct_name + "_" + var.var_name + ": {\n")
976             c_params = []
977             for idx, (field_map, _) in enumerate(var.fields):
978                 if field_map.ret_conv is not None:
979                     out_c += ("\t\t\t" + field_map.ret_conv[0].replace("\n", "\n\t\t\t"))
980                     if var.tuple_variant:
981                         out_c += "obj->" + camel_to_snake(var.var_name)
982                     else:
983                         out_c += "obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name
984                     out_c += (field_map.ret_conv[1].replace("\n", "\n\t\t\t") + "\n")
985                     c_params.append(field_map.ret_conv_name)
986                 else:
987                     if var.tuple_variant:
988                         c_params.append("obj->" + camel_to_snake(var.var_name))
989                     else:
990                         c_params.append("obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name)
991             out_c += ("\t\t\treturn " + self.c_constr_native_complex_enum(struct_name, var.var_name, c_params) + ";\n")
992             out_c += ("\t\t}\n")
993         out_c += ("\t\tdefault: abort();\n")
994         out_c += ("\t}\n}\n")
995         out_java_enum += java_hu_class
996         self.struct_file_suffixes[java_hu_type] = java_hu_subclasses
997         self.obj_defined([java_hu_type], "structs")
998         return (out_java, out_java_enum, out_c)
999
1000     def map_opaque_struct(self, struct_name, struct_doc_comment):
1001         implementations = ""
1002         method_header = ""
1003         if struct_name.startswith("LDKLocked"):
1004             return "NOT IMPLEMENTED"
1005
1006         hu_name = struct_name.replace("LDKC2Tuple", "TwoTuple").replace("LDKC3Tuple", "ThreeTuple").replace("LDK", "")
1007         out_opaque_struct_human = f"""{self.hu_struct_file_prefix}
1008
1009 export class {hu_name} extends CommonBase {implementations}{{
1010         /* @internal */
1011         public constructor(_dummy: object, ptr: number) {{
1012                 super(ptr, bindings.{struct_name.replace("LDK","")}_free);
1013         }}
1014
1015 """
1016         self.obj_defined([hu_name], "structs")
1017         return out_opaque_struct_human
1018
1019     def map_tuple(self, struct_name):
1020         return self.map_opaque_struct(struct_name, "A Tuple")
1021
1022     def map_result(self, struct_name, res_map, err_map):
1023         human_ty = struct_name.replace("LDKCResult", "Result")
1024
1025         suffixes = f"export class {human_ty}_OK extends {human_ty} {{\n"
1026         if res_map.java_hu_ty != "void":
1027             suffixes += "\tpublic res: " + res_map.java_hu_ty + ";\n"
1028         suffixes += f"""
1029         /* @internal */
1030         public constructor(_dummy: object, ptr: number) {{
1031                 super(_dummy, ptr);
1032 """
1033         if res_map.java_hu_ty == "void":
1034             pass
1035         elif res_map.to_hu_conv is not None:
1036             suffixes += "\t\tconst res: " + res_map.java_ty + " = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1037             suffixes += "\t\t" + res_map.to_hu_conv.replace("\n", "\n\t\t")
1038             suffixes += "\n\t\tthis.res = " + res_map.to_hu_conv_name + ";\n"
1039         else:
1040             suffixes += "\t\tthis.res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1041         suffixes += "\t}\n}\n"
1042
1043         suffixes += f"export class {human_ty}_Err extends {human_ty} {{\n"
1044         if err_map.java_hu_ty != "void":
1045             suffixes += "\tpublic err: " + err_map.java_hu_ty + ";\n"
1046         suffixes += f"""
1047         /* @internal */
1048         public constructor(_dummy: object, ptr: number) {{
1049                 super(_dummy, ptr);
1050 """
1051         if err_map.java_hu_ty == "void":
1052             pass
1053         elif err_map.to_hu_conv is not None:
1054             suffixes += "\t\tconst err: " + err_map.java_ty + " = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1055             suffixes += "\t\t" + err_map.to_hu_conv.replace("\n", "\n\t\t")
1056             suffixes += "\n\t\tthis.err = " + err_map.to_hu_conv_name + ";\n"
1057         else:
1058             suffixes += "\t\tthis.err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1059         suffixes += "\t}\n}"
1060
1061         self.struct_file_suffixes[human_ty] = suffixes
1062         self.obj_defined([human_ty], "structs")
1063
1064         return f"""{self.hu_struct_file_prefix}
1065
1066 export class {human_ty} extends CommonBase {{
1067         protected constructor(_dummy: object, ptr: number) {{
1068                 super(ptr, bindings.{struct_name.replace("LDK","")}_free);
1069         }}
1070         /* @internal */
1071         public static constr_from_ptr(ptr: number): {human_ty} {{
1072                 if (bindings.{struct_name.replace("LDK", "")}_is_ok(ptr)) {{
1073                         return new {human_ty}_OK(null, ptr);
1074                 }} else {{
1075                         return new {human_ty}_Err(null, ptr);
1076                 }}
1077         }}
1078 """
1079
1080     def fn_call_body(self, method_name, return_c_ty, return_java_ty, method_argument_string, native_call_argument_string):
1081         has_return_value = return_c_ty != 'void'
1082         needs_decoding = return_c_ty in self.wasm_decoding_map
1083         return_statement = 'return nativeResponseValue;'
1084         if not has_return_value:
1085             return_statement = '// debug statements here'
1086         elif needs_decoding:
1087             converter = self.wasm_decoding_map[return_c_ty]
1088             return_statement = f"return {converter}(nativeResponseValue);"
1089
1090         return f"""\texport function {method_name}({method_argument_string}): {return_java_ty} {{
1091                 if(!isWasmInitialized) {{
1092                         throw new Error("initializeWasm() must be awaited first!");
1093                 }}
1094                 const nativeResponseValue = wasm.TS_{method_name}({native_call_argument_string});
1095                 {return_statement}
1096         }}
1097 """
1098     def map_function(self, argument_types, c_call_string, method_name, meth_n, return_type_info, struct_meth, default_constructor_args, takes_self, takes_self_as_ref, args_known, type_mapping_generator, doc_comment):
1099         out_java = ""
1100         out_c = ""
1101         out_java_struct = None
1102
1103         out_java += ("\t")
1104         out_c += (self.c_fn_ty_pfx)
1105         out_c += (return_type_info.c_ty)
1106         out_java += (return_type_info.java_ty)
1107         if return_type_info.ret_conv is not None:
1108             ret_conv_pfx, ret_conv_sfx = return_type_info.ret_conv
1109         out_java += (" " + method_name + "(")
1110         out_c += (" "  + self.c_fn_name_define_pfx(method_name, True))
1111
1112         method_argument_string = ""
1113         native_call_argument_string = ""
1114         for idx, arg_conv_info in enumerate(argument_types):
1115             if idx != 0:
1116                 method_argument_string += (", ")
1117                 native_call_argument_string += ', '
1118                 out_c += (", ")
1119             if arg_conv_info.c_ty != "void":
1120                 out_c += (arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
1121                 needs_encoding = arg_conv_info.c_ty in self.wasm_encoding_map
1122                 native_argument = arg_conv_info.arg_name
1123                 if needs_encoding:
1124                     converter = self.wasm_encoding_map[arg_conv_info.c_ty]
1125                     native_argument = f"{converter}({arg_conv_info.arg_name})"
1126                 method_argument_string += f"{arg_conv_info.arg_name}: {arg_conv_info.java_ty}"
1127                 native_call_argument_string += native_argument
1128         out_java = self.fn_call_body(method_name, return_type_info.c_ty, return_type_info.java_ty, method_argument_string, native_call_argument_string)
1129
1130         out_java_struct = ""
1131         if not args_known:
1132             out_java_struct += ("\t// Skipped " + method_name + "\n")
1133         else:
1134             if not takes_self:
1135                 out_java_struct += (
1136                         "\tpublic static constructor_" + meth_n + "(")
1137             else:
1138                 out_java_struct += ("\tpublic " + meth_n + "(")
1139             for idx, arg in enumerate(argument_types):
1140                 if idx != 0:
1141                     if not takes_self or idx > 1:
1142                         out_java_struct += (", ")
1143                 elif takes_self:
1144                     continue
1145                 if arg.java_ty != "void":
1146                     if arg.arg_name in default_constructor_args:
1147                         for explode_idx, explode_arg in enumerate(default_constructor_args[arg.arg_name]):
1148                             if explode_idx != 0:
1149                                 out_java_struct += (", ")
1150                             out_java_struct += arg.arg_name + "_" + explode_arg.arg_name + ": " + explode_arg.java_hu_ty
1151                     else:
1152                         out_java_struct += arg.arg_name + ": " + arg.java_hu_ty
1153
1154         out_c += (") {\n")
1155         if out_java_struct is not None:
1156             out_java_struct += "): " + return_type_info.java_hu_ty + " {\n"
1157         for info in argument_types:
1158             if info.arg_conv is not None:
1159                 out_c += ("\t" + info.arg_conv.replace('\n', "\n\t") + "\n")
1160         if return_type_info.ret_conv is not None:
1161             out_c += ("\t" + ret_conv_pfx.replace('\n', '\n\t'))
1162         elif return_type_info.c_ty != "void":
1163             out_c += ("\t" + return_type_info.c_ty + " ret_val = ")
1164         else:
1165             out_c += ("\t")
1166         if c_call_string is None:
1167             out_c += (method_name + "(")
1168         else:
1169             out_c += (c_call_string)
1170         for idx, info in enumerate(argument_types):
1171             if info.arg_conv_name is not None:
1172                 if idx != 0:
1173                     out_c += (", ")
1174                 elif c_call_string is not None:
1175                     continue
1176                 out_c += (info.arg_conv_name)
1177         out_c += (")")
1178         if return_type_info.ret_conv is not None:
1179             out_c += (ret_conv_sfx.replace('\n', '\n\t'))
1180         else:
1181             out_c += (";")
1182         for info in argument_types:
1183             if info.arg_conv_cleanup is not None:
1184                 out_c += ("\n\t" + info.arg_conv_cleanup.replace("\n", "\n\t"))
1185         if return_type_info.ret_conv is not None:
1186             out_c += ("\n\treturn " + return_type_info.ret_conv_name + ";")
1187         elif return_type_info.c_ty != "void":
1188             out_c += ("\n\treturn ret_val;")
1189         out_c += ("\n}\n\n")
1190
1191         if args_known:
1192             out_java_struct += ("\t\t")
1193             if return_type_info.java_ty != "void":
1194                 out_java_struct += "const ret: " + return_type_info.java_ty + " = "
1195             out_java_struct += ("bindings." + method_name + "(")
1196             for idx, info in enumerate(argument_types):
1197                 if idx != 0:
1198                     out_java_struct += (", ")
1199                 if idx == 0 and takes_self:
1200                     out_java_struct += ("this.ptr")
1201                 elif info.arg_name in default_constructor_args:
1202                     out_java_struct += ("bindings." + info.java_hu_ty + "_new(")
1203                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1204                         if explode_idx != 0:
1205                             out_java_struct += (", ")
1206                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1207                         if explode_arg.from_hu_conv is not None:
1208                             out_java_struct += (
1209                                 explode_arg.from_hu_conv[0].replace(explode_arg.arg_name, expl_arg_name))
1210                         else:
1211                             out_java_struct += (expl_arg_name)
1212                     out_java_struct += (")")
1213                 elif info.from_hu_conv is not None:
1214                     out_java_struct += (info.from_hu_conv[0])
1215                 else:
1216                     out_java_struct += (info.arg_name)
1217             out_java_struct += (");\n")
1218             if return_type_info.to_hu_conv is not None:
1219                 if not takes_self:
1220                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t").replace("this",
1221                                                                                                              return_type_info.to_hu_conv_name) + "\n")
1222                 else:
1223                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t") + "\n")
1224
1225             for idx, info in enumerate(argument_types):
1226                 if idx == 0 and takes_self:
1227                     pass
1228                 elif info.arg_name in default_constructor_args:
1229                     for explode_arg in default_constructor_args[info.arg_name]:
1230                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1231                         if explode_arg.from_hu_conv is not None and return_type_info.to_hu_conv_name:
1232                             out_java_struct += ("\t\t" + explode_arg.from_hu_conv[1].replace(explode_arg.arg_name,
1233                                                                                              expl_arg_name).replace(
1234                                 "this", return_type_info.to_hu_conv_name) + ";\n")
1235                 elif info.from_hu_conv is not None and info.from_hu_conv[1] != "":
1236                     if not takes_self and return_type_info.to_hu_conv_name is not None:
1237                         out_java_struct += (
1238                                 "\t\t" + info.from_hu_conv[1].replace("this", return_type_info.to_hu_conv_name).replace("\n", "\n\t\t") + ";\n")
1239                     else:
1240                         out_java_struct += ("\t\t" + info.from_hu_conv[1].replace("\n", "\n\t\t") + ";\n")
1241
1242             if return_type_info.to_hu_conv_name is not None:
1243                 out_java_struct += ("\t\treturn " + return_type_info.to_hu_conv_name + ";\n")
1244             elif return_type_info.java_ty != "void" and return_type_info.rust_obj != "LDK" + struct_meth:
1245                 out_java_struct += ("\t\treturn ret;\n")
1246             out_java_struct += ("\t}\n\n")
1247
1248         return (out_java, out_c, out_java_struct)
1249
1250     def cleanup(self):
1251         for struct in self.struct_file_suffixes:
1252             with open(self.outdir + "/structs/" + struct + self.file_ext, "a") as src:
1253                 src.write(self.struct_file_suffixes[struct])