// Protocol Buffers - Google's data interchange format
// Copyright 2023 Google LLC.  All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd

#ifndef UPB_REFLECTION_DEF_BUILDER_INTERNAL_H_
#define UPB_REFLECTION_DEF_BUILDER_INTERNAL_H_

#include <setjmp.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>

#include "upb/base/status.h"
#include "upb/base/string_view.h"
#include "upb/hash/common.h"
#include "upb/hash/str_table.h"
#include "upb/mem/arena.h"
#include "upb/mini_descriptor/decode.h"
#include "upb/mini_table/file.h"
#include "upb/reflection/common.h"
#include "upb/reflection/def_type.h"
#include "upb/reflection/descriptor_bootstrap.h"
#include "upb/reflection/internal/def_pool.h"

// Must be last.
#include "upb/port/def.inc"

// We want to copy the options verbatim into the destination options proto.
// We use serialize+parse as our deep copy.
#define _UPB_FREEZE_OPTIONS(target, options_type) \
  upb_Message_Freeze((upb_Message*)target, UPB_DESC_MINITABLE(options_type))

#define UPB_DEF_SET_OPTIONS(target, desc_type, options_type, proto)        \
  if (google_protobuf_##desc_type##_has_options(proto)) {                           \
    size_t size;                                                           \
    char* pb = google_protobuf_##options_type##_serialize(                          \
        google_protobuf_##desc_type##_options(proto), ctx->tmp_arena, &size);       \
    if (!pb) _upb_DefBuilder_OomErr(ctx);                                  \
    target = google_protobuf_##options_type##_parse_ex(                             \
        pb, size, _upb_DefPool_GeneratedExtensionRegistry(ctx->symtab), 0, \
        _upb_DefBuilder_Arena(ctx));                                       \
    if (!target) _upb_DefBuilder_OomErr(ctx);                              \
    _UPB_FREEZE_OPTIONS(target, options_type);                             \
  } else {                                                                 \
    target = (const google_protobuf_##options_type*)kUpbDefOptDefault;              \
  }

#ifdef __cplusplus
extern "C" {
#endif

struct upb_DefBuilder {
  upb_DefPool* symtab;
  upb_strtable feature_cache;          // Caches features by identity.
  google_protobuf_FeatureSet* legacy_features;  // For computing legacy features.
  char* tmp_buf;                       // Temporary buffer in tmp_arena.
  size_t tmp_buf_size;                 // Size of temporary buffer.
  upb_FileDef* file;                   // File we are building.
  upb_Arena* arena;                    // Allocate defs here.
  upb_Arena* tmp_arena;                // For temporary allocations.
  upb_Status* status;                  // Record errors here.
  const upb_MiniTableFile* layout;     // NULL if we should build layouts.
  upb_MiniTablePlatform platform;      // Platform we are targeting.
  int enum_count;                      // Count of enums built so far.
  int msg_count;                       // Count of messages built so far.
  int ext_count;                       // Count of extensions built so far.
  jmp_buf err;                         // longjmp() on error.
};

extern const char* kUpbDefOptDefault;

// ctx->status has already been set elsewhere so just fail/longjmp()
UPB_NORETURN void _upb_DefBuilder_FailJmp(upb_DefBuilder* ctx);

UPB_NORETURN void _upb_DefBuilder_Errf(upb_DefBuilder* ctx, const char* fmt,
                                       ...) UPB_PRINTF(2, 3);
UPB_NORETURN void _upb_DefBuilder_OomErr(upb_DefBuilder* ctx);

const char* _upb_DefBuilder_MakeFullName(upb_DefBuilder* ctx,
                                         const char* prefix,
                                         upb_StringView name);

// Given a symbol and the base symbol inside which it is defined,
// find the symbol's definition.
const void* _upb_DefBuilder_ResolveAny(upb_DefBuilder* ctx,
                                       const char* from_name_dbg,
                                       const char* base, upb_StringView sym,
                                       upb_deftype_t* type);

const void* _upb_DefBuilder_Resolve(upb_DefBuilder* ctx,
                                    const char* from_name_dbg, const char* base,
                                    upb_StringView sym, upb_deftype_t type);

char _upb_DefBuilder_ParseEscape(upb_DefBuilder* ctx, const upb_FieldDef* f,
                                 const char** src, const char* end);

const char* _upb_DefBuilder_FullToShort(const char* fullname);

UPB_INLINE void* _upb_DefBuilder_Alloc(upb_DefBuilder* ctx, size_t bytes) {
  if (bytes == 0) return NULL;
  void* ret = upb_Arena_Malloc(ctx->arena, bytes);
  if (!ret) _upb_DefBuilder_OomErr(ctx);
  return ret;
}

/* Allocates an array of `count` elements, checking for size_t overflow */
UPB_INLINE void* _upb_DefBuilder_AllocCounted(upb_DefBuilder* ctx, size_t size,
                                              size_t count) {
  if (count == 0) return NULL;
  if (SIZE_MAX / size < count) {
    _upb_DefBuilder_OomErr(ctx);
  }
  return _upb_DefBuilder_Alloc(ctx, size * count);
}

#define UPB_DEFBUILDER_ALLOCARRAY(ctx, type, count) \
  ((type*)_upb_DefBuilder_AllocCounted(ctx, sizeof(type), (count)))

// Adds a symbol |v| to the symtab, which must be a def pointer previously
// packed with pack_def(). The def's pointer to upb_FileDef* must be set before
// adding, so we know which entries to remove if building this file fails.
UPB_INLINE void _upb_DefBuilder_Add(upb_DefBuilder* ctx, const char* name,
                                    upb_value v) {
  upb_StringView sym = {.data = name, .size = strlen(name)};
  bool ok = _upb_DefPool_InsertSym(ctx->symtab, sym, v, ctx->status);
  if (!ok) _upb_DefBuilder_FailJmp(ctx);
}

UPB_INLINE upb_Arena* _upb_DefBuilder_Arena(const upb_DefBuilder* ctx) {
  return ctx->arena;
}

UPB_INLINE upb_FileDef* _upb_DefBuilder_File(const upb_DefBuilder* ctx) {
  return ctx->file;
}

// This version of CheckIdent() is only called by other, faster versions after
// they detect a parsing error.
void _upb_DefBuilder_CheckIdentSlow(upb_DefBuilder* ctx, upb_StringView name,
                                    bool full);

// Verify a full identifier string. This is slightly more complicated than
// verifying a relative identifier string because we must track '.' chars.
UPB_INLINE void _upb_DefBuilder_CheckIdentFull(upb_DefBuilder* ctx,
                                               upb_StringView name) {
  bool good = name.size > 0;
  bool start = true;

  for (size_t i = 0; i < name.size; i++) {
    const char c = name.data[i];
    const char d = c | 0x20;  // force lowercase
    const bool is_alpha = (('a' <= d) & (d <= 'z')) | (c == '_');
    // Accept a leading digit even though protoc would reject it because the
    // C++ DescriptorPool accepts it, and upb should be as relaxed as C++.
    const bool is_number = ('0' <= c) & (c <= '9');
    const bool is_dot = (c == '.') & !start;

    good &= is_alpha | is_number | is_dot;
    start = (c == '.');
  }

  if (!good || start) _upb_DefBuilder_CheckIdentSlow(ctx, name, true);
}

UPB_INLINE bool _upb_DefBuilder_IsLegacyEdition(google_protobuf_Edition edition) {
  // Should only be called for a real edition, not a placeholder like
  // EDITION_LEGACY.
  UPB_ASSERT(edition >= google_protobuf_EDITION_PROTO2);
  return edition <= google_protobuf_EDITION_PROTO3;
}

// Returns true if the returned feature set is new and must be populated.
bool _upb_DefBuilder_GetOrCreateFeatureSet(upb_DefBuilder* ctx,
                                           const google_protobuf_FeatureSet* parent,
                                           upb_StringView key,
                                           google_protobuf_FeatureSet** set);

const google_protobuf_FeatureSet* _upb_DefBuilder_DoResolveFeatures(
    upb_DefBuilder* ctx, const google_protobuf_FeatureSet* parent,
    const google_protobuf_FeatureSet* child, bool is_implicit);

UPB_INLINE const google_protobuf_FeatureSet* _upb_DefBuilder_ResolveFeatures(
    upb_DefBuilder* ctx, const google_protobuf_FeatureSet* parent,
    const google_protobuf_FeatureSet* child) {
  return _upb_DefBuilder_DoResolveFeatures(ctx, parent, child, false);
}

#ifdef __cplusplus
} /* extern "C" */
#endif

#include "upb/port/undef.inc"

#endif /* UPB_REFLECTION_DEF_BUILDER_INTERNAL_H_ */
