Cai Chang

import inspect
from datetime import datetime, timezone
from typing import Any

from redb.extractors.enum import Tag
from redb.extractors.macho_extractor import MachOExtractor
from redb.models.dataclasses import MachOExport


class MachOExportExtractor(MachOExtractor):

    def __init__(
        self,
        filepath,
        log,
        exporters=None,
        index_prefix=None,
        elastic_index=None,
        known_benign=False,
        known_malicious=False,
        macho=None,
    ):
        super().__init__(
            filepath,
            log,
            exporters,
            index_prefix,
            elastic_index,
            known_benign,
            known_malicious,
            macho,
        )
        self.elastic_index = self.index_prefix + "-macho_exports"
        self.log.debug(inspect.currentframe().f_code.co_name)

    def tag(self):
        return Tag.MACHO_EXPORT.value

    def _extract_exports(self, arch_name=None):
        """Extract export information from the MachO binary for a specific architecture."""
        self.log.debug(inspect.currentframe().f_code.co_name)

        if not self.macho:
            return None

        try:
            # Get exported symbols using new API for specific architecture
            exported_symbols = self.macho.get_exported_symbols(arch=arch_name)

            # Extract all exported symbols (may be empty for some binaries)
            # Handle None or empty dict
            if not exported_symbols:
                exported_symbols = {}
            all_symbols = []
            for dylib_name, symbols in exported_symbols.items():
                # Process symbol names
                for symbol in symbols:
                    if isinstance(symbol, bytes):
                        symbol = symbol.decode('utf-8', errors='replace')
                    all_symbols.append(symbol)

            # Create export dataclass
            macho_export = MachOExport(
                macho_exports_total=len(all_symbols),
                macho_export_symbols=all_symbols  # Empty list is fine, but None is not allowed for Array type
            )

            return macho_export

        except Exception as e:
            self.log.error(f"Error extracting MachO exports for arch {arch_name}: {e}")
            return None

    def extract(self):
        self.log.debug(inspect.currentframe().f_code.co_name)
        try:
            # Get architectures (macho is already parsed in base class)
            architectures = self.macho.get_architectures()
            if len(architectures) > 1:
                # FAT binary - return list of exports for each architecture
                results = []
                for arch_name in architectures:
                    exports = self._extract_exports(arch_name)
                    if exports:
                        exports.arch_identifier = arch_name
                        results.append(exports)
                return results
            else:
                # Single architecture - return single result
                return self._extract_exports(architectures[0] if architectures else None)
        except Exception as e:
            self.log.error(f"Error extracting MachO exports: {e}")
            return None

    def prepare_export_data(self, exporter_type: str) -> Any:
        if exporter_type == "ElasticsearchExporter":
            return self.extract()
        elif exporter_type == "ClickHouseExporter":
            if not self.macho:
                return None

            # Get architectures (macho is already parsed in base class)
            try:
                architectures = self.macho.get_architectures()
                is_fat = len(architectures) > 1
            except Exception as e:
                self.log.error(f"Could not get architectures: {e}")
                return None

            data = []
            current_time = datetime.now(timezone.utc)

            # Loop through each architecture (1 for single, multiple for FAT)
            for arch_name in architectures:
                # Get architecture-specific sha256
                try:
                    arch_general_info = self.macho.get_general_info(arch=arch_name)
                    arch_header_raw = self.macho.get_macho_header(arch=arch_name)
                    arch_sha256 = arch_general_info.get('SHA256', self.sha256)
                    arch_cputype_raw = arch_header_raw.get('cputype', 0) if arch_header_raw else 0
                except Exception as e:
                    self.log.warning(f"Could not get arch-specific data for {arch_name}: {e}")
                    arch_sha256 = self.sha256
                    arch_cputype_raw = 0

                # Get exports for this architecture
                macho_export = self._extract_exports(arch_name)
                if not macho_export:
                    continue

                data.append([
                    arch_sha256,                          # sha256 (arch-specific)
                    macho_export.macho_exports_total,     # macho_exports_total
                    macho_export.macho_export_symbols,    # macho_export_symbols (keep as array!)
                    current_time,                         # analysis_date
                ])

            column_names = [
                'sha256',
                'macho_exports_total', 'macho_export_symbols',
                'analysis_date'
            ]

            if not data:
                return None

            column_type_names = [
                'FixedString(64)',
                'UInt32', 'Array(Nullable(String))',
                'DateTime64(3, \'UTC\')'
            ]

            return (data, column_names, column_type_names)

        return None

    def get_clickhouse_table(self) -> str:
        return "redb_macho_exports"