From ea239473e0881d0be704c131223fd026a89d3fbc Mon Sep 17 00:00:00 2001
From: Henry8192 <50559854+Henry8192@users.noreply.github.com>
Date: Tue, 19 Nov 2024 17:47:15 -0500
Subject: [PATCH 1/4] search timestamp works for unstructured logs

---
 src/clp_ffi_js/ir/StreamReader.cpp            | 270 +++++++++---------
 src/clp_ffi_js/ir/StreamReader.hpp            |   3 +
 .../ir/StructuredIrStreamReader.cpp           |   6 +
 .../ir/StructuredIrStreamReader.hpp           |   3 +
 .../ir/UnstructuredIrStreamReader.cpp         |  24 ++
 .../ir/UnstructuredIrStreamReader.hpp         |   3 +
 6 files changed, 176 insertions(+), 133 deletions(-)

diff --git a/src/clp_ffi_js/ir/StreamReader.cpp b/src/clp_ffi_js/ir/StreamReader.cpp
index d12c8761..f08c3d8a 100644
--- a/src/clp_ffi_js/ir/StreamReader.cpp
+++ b/src/clp_ffi_js/ir/StreamReader.cpp
@@ -26,182 +26,186 @@
 #include <clp_ffi_js/ir/UnstructuredIrStreamReader.hpp>
 
 namespace {
-using ClpFfiJsException = clp_ffi_js::ClpFfiJsException;
-using IRErrorCode = clp::ffi::ir_stream::IRErrorCode;
-
-// Function declarations
-/**
- * Rewinds the reader to the beginning then validates the CLP IR data encoding type.
- * @param reader
- * @throws ClpFfiJsException if the encoding type couldn't be decoded or the encoding type is
- * unsupported.
- */
-auto rewind_reader_and_validate_encoding_type(clp::ReaderInterface& reader) -> void;
-
-/**
- * Gets the version of the IR stream.
- * @param reader
- * @throws ClpFfiJsException if the preamble couldn't be deserialized.
- * @return The IR stream's version.
- */
-auto get_version(clp::ReaderInterface& reader) -> std::string;
-
-auto rewind_reader_and_validate_encoding_type(clp::ReaderInterface& reader) -> void {
-    reader.seek_from_begin(0);
-
-    bool is_four_bytes_encoding{true};
-    if (auto const err{clp::ffi::ir_stream::get_encoding_type(reader, is_four_bytes_encoding)};
-        IRErrorCode::IRErrorCode_Success != err)
-    {
-        throw ClpFfiJsException{
+    using ClpFfiJsException = clp_ffi_js::ClpFfiJsException;
+    using IRErrorCode = clp::ffi::ir_stream::IRErrorCode;
+
+    // Function declarations
+    /**
+     * Rewinds the reader to the beginning then validates the CLP IR data encoding type.
+     * @param reader
+     * @throws ClpFfiJsException if the encoding type couldn't be decoded or the encoding type is
+     * unsupported.
+     */
+    auto rewind_reader_and_validate_encoding_type(clp::ReaderInterface &reader) -> void;
+
+    /**
+     * Gets the version of the IR stream.
+     * @param reader
+     * @throws ClpFfiJsException if the preamble couldn't be deserialized.
+     * @return The IR stream's version.
+     */
+    auto get_version(clp::ReaderInterface &reader) -> std::string;
+
+    auto rewind_reader_and_validate_encoding_type(clp::ReaderInterface &reader) -> void {
+        reader.seek_from_begin(0);
+
+        bool is_four_bytes_encoding{true};
+        if (auto const err{clp::ffi::ir_stream::get_encoding_type(reader, is_four_bytes_encoding)};
+            IRErrorCode::IRErrorCode_Success != err) {
+            throw ClpFfiJsException{
                 clp::ErrorCode::ErrorCode_MetadataCorrupted,
                 __FILENAME__,
                 __LINE__,
                 std::format(
-                        "Failed to decode encoding type: IR error code {}",
-                        clp::enum_to_underlying_type(err)
+                    "Failed to decode encoding type: IR error code {}",
+                    clp::enum_to_underlying_type(err)
                 )
-        };
-    }
-    if (false == is_four_bytes_encoding) {
-        throw ClpFfiJsException{
+            };
+        }
+        if (false == is_four_bytes_encoding) {
+            throw ClpFfiJsException{
                 clp::ErrorCode::ErrorCode_Unsupported,
                 __FILENAME__,
                 __LINE__,
                 "IR stream uses unsupported encoding."
-        };
+            };
+        }
     }
-}
-
-auto get_version(clp::ReaderInterface& reader) -> std::string {
-    // Deserialize metadata bytes from preamble.
-    clp::ffi::ir_stream::encoded_tag_t metadata_type{};
-    std::vector<int8_t> metadata_bytes;
-    auto const err{clp::ffi::ir_stream::deserialize_preamble(reader, metadata_type, metadata_bytes)
-    };
-    if (IRErrorCode::IRErrorCode_Success != err) {
-        throw ClpFfiJsException{
+
+    auto get_version(clp::ReaderInterface &reader) -> std::string {
+        // Deserialize metadata bytes from preamble.
+        clp::ffi::ir_stream::encoded_tag_t metadata_type{};
+        std::vector<int8_t> metadata_bytes;
+        auto const err{
+            clp::ffi::ir_stream::deserialize_preamble(reader, metadata_type, metadata_bytes)
+        };
+        if (IRErrorCode::IRErrorCode_Success != err) {
+            throw ClpFfiJsException{
                 clp::ErrorCode::ErrorCode_Failure,
                 __FILENAME__,
                 __LINE__,
                 std::format(
-                        "Failed to deserialize preamble: IR error code {}",
-                        clp::enum_to_underlying_type(err)
+                    "Failed to deserialize preamble: IR error code {}",
+                    clp::enum_to_underlying_type(err)
                 )
-        };
-    }
+            };
+        }
 
-    std::string version;
-    try {
-        // Deserialize metadata bytes as JSON.
-        std::string_view const metadata_view{
+        std::string version;
+        try {
+            // Deserialize metadata bytes as JSON.
+            std::string_view const metadata_view{
                 clp::size_checked_pointer_cast<char const>(metadata_bytes.data()),
                 metadata_bytes.size()
-        };
-        nlohmann::json const metadata = nlohmann::json::parse(metadata_view);
-        version = metadata.at(clp::ffi::ir_stream::cProtocol::Metadata::VersionKey);
-    } catch (nlohmann::json::exception const& e) {
-        throw ClpFfiJsException{
+            };
+            nlohmann::json const metadata = nlohmann::json::parse(metadata_view);
+            version = metadata.at(clp::ffi::ir_stream::cProtocol::Metadata::VersionKey);
+        } catch (nlohmann::json::exception const &e) {
+            throw ClpFfiJsException{
                 clp::ErrorCode::ErrorCode_MetadataCorrupted,
                 __FILENAME__,
                 __LINE__,
                 std::format("Failed to parse stream's metadata: {}", e.what())
-        };
+            };
+        }
+
+        SPDLOG_INFO("IR version is {}", version);
+        return version;
     }
 
-    SPDLOG_INFO("IR version is {}", version);
-    return version;
-}
-
-EMSCRIPTEN_BINDINGS(ClpStreamReader) {
-    // JS types used as inputs
-    emscripten::register_type<clp_ffi_js::ir::DataArrayTsType>("Uint8Array");
-    emscripten::register_type<clp_ffi_js::ir::LogLevelFilterTsType>("number[] | null");
-    emscripten::register_type<clp_ffi_js::ir::ReaderOptions>("{timestampKey: string} | null");
-
-    // JS types used as outputs
-    emscripten::enum_<clp_ffi_js::ir::StreamType>("IrStreamType")
-            .value("STRUCTURED", clp_ffi_js::ir::StreamType::Structured)
-            .value("UNSTRUCTURED", clp_ffi_js::ir::StreamType::Unstructured);
-    emscripten::register_type<clp_ffi_js::ir::DecodedResultsTsType>(
+    EMSCRIPTEN_BINDINGS(ClpStreamReader) {
+        // JS types used as inputs
+        emscripten::register_type<clp_ffi_js::ir::DataArrayTsType>("Uint8Array");
+        emscripten::register_type<clp_ffi_js::ir::LogLevelFilterTsType>("number[] | null");
+        emscripten::register_type<clp_ffi_js::ir::ReaderOptions>("{timestampKey: string} | null");
+
+        // JS types used as outputs
+        emscripten::enum_<clp_ffi_js::ir::StreamType>("IrStreamType")
+                .value("STRUCTURED", clp_ffi_js::ir::StreamType::Structured)
+                .value("UNSTRUCTURED", clp_ffi_js::ir::StreamType::Unstructured);
+        emscripten::register_type<clp_ffi_js::ir::DecodedResultsTsType>(
             "Array<[string, bigint, number, number]>"
-    );
-    emscripten::register_type<clp_ffi_js::ir::FilteredLogEventMapTsType>("number[] | null");
-    emscripten::class_<clp_ffi_js::ir::StreamReader>("ClpStreamReader")
-            .constructor(
+        );
+        emscripten::register_type<clp_ffi_js::ir::FilteredLogEventMapTsType>("number[] | null");
+        emscripten::class_<clp_ffi_js::ir::StreamReader>("ClpStreamReader")
+                .constructor(
                     &clp_ffi_js::ir::StreamReader::create,
                     emscripten::return_value_policy::take_ownership()
-            )
-            .function("getIrStreamType", &clp_ffi_js::ir::StreamReader::get_ir_stream_type)
-            .function(
+                )
+                .function("getIrStreamType", &clp_ffi_js::ir::StreamReader::get_ir_stream_type)
+                .function(
                     "getNumEventsBuffered",
                     &clp_ffi_js::ir::StreamReader::get_num_events_buffered
-            )
-            .function(
+                )
+                .function(
                     "getFilteredLogEventMap",
                     &clp_ffi_js::ir::StreamReader::get_filtered_log_event_map
-            )
-            .function("filterLogEvents", &clp_ffi_js::ir::StreamReader::filter_log_events)
-            .function("deserializeStream", &clp_ffi_js::ir::StreamReader::deserialize_stream)
-            .function("decodeRange", &clp_ffi_js::ir::StreamReader::decode_range);
-}
-}  // namespace
+                )
+                .function("filterLogEvents", &clp_ffi_js::ir::StreamReader::filter_log_events)
+                .function("deserializeStream", &clp_ffi_js::ir::StreamReader::deserialize_stream)
+                .function("decodeRange", &clp_ffi_js::ir::StreamReader::decode_range)
+                .function("getLogEventIndexByTimestamp",
+                          &clp_ffi_js::ir::StreamReader::find_timestamp_last_occurrence);
+    }
+} // namespace
 
 namespace clp_ffi_js::ir {
-auto StreamReader::create(DataArrayTsType const& data_array, ReaderOptions const& reader_options)
+    auto StreamReader::create(DataArrayTsType const &data_array,
+                              ReaderOptions const &reader_options)
         -> std::unique_ptr<StreamReader> {
-    auto const length{data_array["length"].as<size_t>()};
-    SPDLOG_INFO("StreamReader::create: got buffer of length={}", length);
-
-    // Copy array from JavaScript to C++.
-    clp::Array<char> data_buffer{length};
-    // NOLINTBEGIN(cppcoreguidelines-pro-type-reinterpret-cast)
-    emscripten::val::module_property("HEAPU8")
-            .call<void>("set", data_array, reinterpret_cast<uintptr_t>(data_buffer.data()));
-    // NOLINTEND(cppcoreguidelines-pro-type-reinterpret-cast)
-
-    auto zstd_decompressor{std::make_unique<ZstdDecompressor>()};
-    zstd_decompressor->open(data_buffer.data(), length);
-
-    rewind_reader_and_validate_encoding_type(*zstd_decompressor);
-
-    // Validate the stream's version and decide which type of IR stream reader to create.
-    auto pos = zstd_decompressor->get_pos();
-    auto const version{get_version(*zstd_decompressor)};
-    try {
-        auto const version_validation_result{clp::ffi::ir_stream::validate_protocol_version(version)
-        };
-        if (clp::ffi::ir_stream::IRProtocolErrorCode::Supported == version_validation_result) {
-            zstd_decompressor->seek_from_begin(0);
-            return std::make_unique<StructuredIrStreamReader>(StructuredIrStreamReader::create(
+        auto const length{data_array["length"].as<size_t>()};
+        SPDLOG_INFO("StreamReader::create: got buffer of length={}", length);
+
+        // Copy array from JavaScript to C++.
+        clp::Array<char> data_buffer{length};
+        // NOLINTBEGIN(cppcoreguidelines-pro-type-reinterpret-cast)
+        emscripten::val::module_property("HEAPU8")
+                .call<void>("set", data_array, reinterpret_cast<uintptr_t>(data_buffer.data()));
+        // NOLINTEND(cppcoreguidelines-pro-type-reinterpret-cast)
+
+        auto zstd_decompressor{std::make_unique<ZstdDecompressor>()};
+        zstd_decompressor->open(data_buffer.data(), length);
+
+        rewind_reader_and_validate_encoding_type(*zstd_decompressor);
+
+        // Validate the stream's version and decide which type of IR stream reader to create.
+        auto pos = zstd_decompressor->get_pos();
+        auto const version{get_version(*zstd_decompressor)};
+        try {
+            auto const version_validation_result{
+                clp::ffi::ir_stream::validate_protocol_version(version)
+            };
+            if (clp::ffi::ir_stream::IRProtocolErrorCode::Supported == version_validation_result) {
+                zstd_decompressor->seek_from_begin(0);
+                return std::make_unique<StructuredIrStreamReader>(StructuredIrStreamReader::create(
                     std::move(zstd_decompressor),
                     std::move(data_buffer),
                     reader_options
-            ));
-        }
-        if (clp::ffi::ir_stream::IRProtocolErrorCode::BackwardCompatible
-            == version_validation_result)
-        {
-            zstd_decompressor->seek_from_begin(pos);
-            return std::make_unique<UnstructuredIrStreamReader>(UnstructuredIrStreamReader::create(
-                    std::move(zstd_decompressor),
-                    std::move(data_buffer)
-            ));
-        }
-    } catch (ZstdDecompressor::OperationFailed const& e) {
-        throw ClpFfiJsException{
+                ));
+            }
+            if (clp::ffi::ir_stream::IRProtocolErrorCode::BackwardCompatible
+                == version_validation_result) {
+                zstd_decompressor->seek_from_begin(pos);
+                return std::make_unique<UnstructuredIrStreamReader>(
+                    UnstructuredIrStreamReader::create(
+                        std::move(zstd_decompressor),
+                        std::move(data_buffer)
+                    ));
+            }
+        } catch (ZstdDecompressor::OperationFailed const &e) {
+            throw ClpFfiJsException{
                 clp::ErrorCode::ErrorCode_Failure,
                 __FILENAME__,
                 __LINE__,
                 std::format("Unable to rewind zstd decompressor: {}", e.what())
-        };
-    }
+            };
+        }
 
-    throw ClpFfiJsException{
+        throw ClpFfiJsException{
             clp::ErrorCode::ErrorCode_Unsupported,
             __FILENAME__,
             __LINE__,
             std::format("Unable to create reader for IR stream with version {}.", version)
-    };
-}
-}  // namespace clp_ffi_js::ir
+        };
+    }
+} // namespace clp_ffi_js::ir
diff --git a/src/clp_ffi_js/ir/StreamReader.hpp b/src/clp_ffi_js/ir/StreamReader.hpp
index 06e7c094..ec90520c 100644
--- a/src/clp_ffi_js/ir/StreamReader.hpp
+++ b/src/clp_ffi_js/ir/StreamReader.hpp
@@ -7,6 +7,7 @@
 
 #include <clp/streaming_compression/zstd/Decompressor.hpp>
 #include <emscripten/val.h>
+#include <ir/types.hpp>
 
 namespace clp_ffi_js::ir {
 // JS types used as inputs
@@ -100,6 +101,8 @@ class StreamReader {
     [[nodiscard]] virtual auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType = 0;
 
+    [[nodiscard]] virtual auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp)
+            -> std::ptrdiff_t = 0;
 protected:
     explicit StreamReader() = default;
 };
diff --git a/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp b/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
index 799da91c..8c69ac55 100644
--- a/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
+++ b/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
@@ -182,6 +182,12 @@ auto StructuredIrStreamReader::decode_range(size_t begin_idx, size_t end_idx, bo
     return DecodedResultsTsType(results);
 }
 
+auto StructuredIrStreamReader::find_timestamp_last_occurrence(
+        clp::ir::epoch_time_ms_t input_timestamp
+) -> std::ptrdiff_t {
+    return 0;
+}
+
 StructuredIrStreamReader::StructuredIrStreamReader(
         StreamReaderDataContext<StructuredIrDeserializer>&& stream_reader_data_context,
         std::shared_ptr<std::vector<clp::ffi::KeyValuePairLogEvent>> deserialized_log_events
diff --git a/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp b/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
index e93dee03..b443ddbb 100644
--- a/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
+++ b/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
@@ -171,6 +171,9 @@ class StructuredIrStreamReader : public StreamReader {
     [[nodiscard]] auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType override;
 
+    [[nodiscard]] auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp)
+            -> std::ptrdiff_t override;
+
 private:
     // Constructor
     explicit StructuredIrStreamReader(
diff --git a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
index 37363fd0..661858b4 100644
--- a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
+++ b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
@@ -212,6 +212,30 @@ auto UnstructuredIrStreamReader::decode_range(size_t begin_idx, size_t end_idx,
     return DecodedResultsTsType(results);
 }
 
+auto UnstructuredIrStreamReader::find_timestamp_last_occurrence(
+        clp::ir::epoch_time_ms_t input_timestamp
+) -> std::ptrdiff_t {
+    // Use std::lower_bound with a custom comparator
+    auto it = std::lower_bound(
+            m_encoded_log_events.begin(),
+            m_encoded_log_events.end(),
+            input_timestamp,
+            [](const LogEventWithFilterData<UnstructuredLogEvent>& event, clp::ir::epoch_time_ms_t timestamp) {
+                return event.get_timestamp() <= timestamp;
+            }
+    );
+
+    // Adjust the iterator to find the last valid index
+    if (it == m_encoded_log_events.end() || it->get_timestamp() > input_timestamp) {
+        if (it == m_encoded_log_events.begin()) {
+            return -1;  // No element satisfies the condition
+        }
+        --it;
+    }
+
+    return std::distance(m_encoded_log_events.begin(), it);
+}
+
 UnstructuredIrStreamReader::UnstructuredIrStreamReader(
         StreamReaderDataContext<UnstructuredIrDeserializer>&& stream_reader_data_context
 )
diff --git a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
index 20137c39..e14267a8 100644
--- a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
+++ b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
@@ -78,6 +78,9 @@ class UnstructuredIrStreamReader : public StreamReader {
     [[nodiscard]] auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType override;
 
+    [[nodiscard]] auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp)
+            -> std::ptrdiff_t override;
+
 private:
     // Constructor
     explicit UnstructuredIrStreamReader(

From 3ee05a261cc5e4fac0cffd04adb722731d2445f9 Mon Sep 17 00:00:00 2001
From: Henry8192 <50559854+Henry8192@users.noreply.github.com>
Date: Thu, 19 Dec 2024 14:15:22 -0500
Subject: [PATCH 2/4] fix lint

---
 src/clp_ffi_js/ir/StreamReader.cpp               | 6 ++++--
 src/clp_ffi_js/ir/StreamReader.hpp               | 8 +++++---
 src/clp_ffi_js/ir/StructuredIrStreamReader.hpp   | 4 ++--
 src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp | 5 ++---
 src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp | 4 ++--
 5 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/clp_ffi_js/ir/StreamReader.cpp b/src/clp_ffi_js/ir/StreamReader.cpp
index 86447326..bd065ef8 100644
--- a/src/clp_ffi_js/ir/StreamReader.cpp
+++ b/src/clp_ffi_js/ir/StreamReader.cpp
@@ -146,8 +146,10 @@ EMSCRIPTEN_BINDINGS(ClpStreamReader) {
             .function("filterLogEvents", &clp_ffi_js::ir::StreamReader::filter_log_events)
             .function("deserializeStream", &clp_ffi_js::ir::StreamReader::deserialize_stream)
             .function("decodeRange", &clp_ffi_js::ir::StreamReader::decode_range)
-            .function("getLogEventIndexByTimestamp",
-                      &clp_ffi_js::ir::StreamReader::find_timestamp_last_occurrence);
+            .function(
+                    "getLogEventIndexByTimestamp",
+                    &clp_ffi_js::ir::StreamReader::find_timestamp_last_occurrence
+            );
 }
 }  // namespace
 
diff --git a/src/clp_ffi_js/ir/StreamReader.hpp b/src/clp_ffi_js/ir/StreamReader.hpp
index b8c35ad1..9ce68d32 100644
--- a/src/clp_ffi_js/ir/StreamReader.hpp
+++ b/src/clp_ffi_js/ir/StreamReader.hpp
@@ -5,6 +5,7 @@
 #include <concepts>
 #include <cstddef>
 #include <cstdint>
+#include <ir/types.hpp>
 #include <memory>
 #include <optional>
 #include <string>
@@ -15,7 +16,6 @@
 #include <clp/type_utils.hpp>
 #include <emscripten/em_asm.h>
 #include <emscripten/val.h>
-#include <ir/types.hpp>
 #include <spdlog/spdlog.h>
 
 #include <clp_ffi_js/constants.hpp>
@@ -125,8 +125,10 @@ class StreamReader {
     [[nodiscard]] virtual auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType = 0;
 
-    [[nodiscard]] virtual auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp)
-            -> std::ptrdiff_t = 0;
+    [[nodiscard]] virtual auto find_timestamp_last_occurrence(
+            clp::ir::epoch_time_ms_t input_timestamp
+    ) -> std::ptrdiff_t = 0;
+
 protected:
     explicit StreamReader() = default;
 
diff --git a/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp b/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
index 748cc0b1..1af21d96 100644
--- a/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
+++ b/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
@@ -74,8 +74,8 @@ class StructuredIrStreamReader : public StreamReader {
     [[nodiscard]] auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType override;
 
-    [[nodiscard]] auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp)
-            -> std::ptrdiff_t override;
+    [[nodiscard]] auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp
+    ) -> std::ptrdiff_t override;
 
 private:
     // Constructor
diff --git a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
index 478edcec..5e0994f4 100644
--- a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
+++ b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
@@ -166,9 +166,8 @@ auto UnstructuredIrStreamReader::find_timestamp_last_occurrence(
             m_encoded_log_events.begin(),
             m_encoded_log_events.end(),
             input_timestamp,
-            [](const LogEventWithFilterData<UnstructuredLogEvent>& event, clp::ir::epoch_time_ms_t timestamp) {
-                return event.get_timestamp() <= timestamp;
-            }
+            [](LogEventWithFilterData<UnstructuredLogEvent> const& event,
+               clp::ir::epoch_time_ms_t timestamp) { return event.get_timestamp() <= timestamp; }
     );
 
     // Adjust the iterator to find the last valid index
diff --git a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
index 81ee930e..3fffdf6c 100644
--- a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
+++ b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
@@ -71,8 +71,8 @@ class UnstructuredIrStreamReader : public StreamReader {
     [[nodiscard]] auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType override;
 
-    [[nodiscard]] auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp)
-            -> std::ptrdiff_t override;
+    [[nodiscard]] auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp
+    ) -> std::ptrdiff_t override;
 
 private:
     // Constructor

From f1a71a1304e169313c994f46f089b114b76099d4 Mon Sep 17 00:00:00 2001
From: Henry8192 <50559854+Henry8192@users.noreply.github.com>
Date: Sun, 22 Dec 2024 00:36:19 -0500
Subject: [PATCH 3/4] implement structured logs search by timestamp

---
 .../ir/StructuredIrStreamReader.cpp           | 20 ++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp b/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
index 01c75bd3..36832845 100644
--- a/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
+++ b/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
@@ -150,7 +150,25 @@ auto StructuredIrStreamReader::decode_range(size_t begin_idx, size_t end_idx, bo
 auto StructuredIrStreamReader::find_timestamp_last_occurrence(
         clp::ir::epoch_time_ms_t input_timestamp
 ) -> std::ptrdiff_t {
-    return 0;
+    // Use std::lower_bound with a custom comparator
+    auto it = std::lower_bound(
+            m_deserialized_log_events->begin(),
+            m_deserialized_log_events->end(),
+            input_timestamp,
+            [](const LogEventWithFilterData<StructuredLogEvent>& event, clp::ir::epoch_time_ms_t timestamp) {
+                return event.get_timestamp() <= timestamp;
+            }
+    );
+
+    // Adjust the iterator to find the last valid index
+    if (it == m_deserialized_log_events->end() || it->get_timestamp() > input_timestamp) {
+        if (it == m_deserialized_log_events->begin()) {
+            return -1;  // No element satisfies the condition
+        }
+        --it;
+    }
+
+    return std::distance(m_deserialized_log_events->begin(), it);
 }
 
 StructuredIrStreamReader::StructuredIrStreamReader(

From c423ec5bc58298fea9bba6841e04f78ff7b5902f Mon Sep 17 00:00:00 2001
From: Henry8192 <50559854+Henry8192@users.noreply.github.com>
Date: Fri, 27 Dec 2024 15:54:08 -0500
Subject: [PATCH 4/4] address partial changes from review

---
 src/clp_ffi_js/ir/StreamReader.cpp               |  3 ++-
 src/clp_ffi_js/ir/StreamReader.hpp               | 16 +++++++++++-----
 src/clp_ffi_js/ir/StructuredIrStreamReader.cpp   | 15 +++++++--------
 src/clp_ffi_js/ir/StructuredIrStreamReader.hpp   |  5 +++--
 src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp |  8 ++++----
 src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp |  4 ++--
 6 files changed, 29 insertions(+), 22 deletions(-)

diff --git a/src/clp_ffi_js/ir/StreamReader.cpp b/src/clp_ffi_js/ir/StreamReader.cpp
index bd065ef8..ea015a35 100644
--- a/src/clp_ffi_js/ir/StreamReader.cpp
+++ b/src/clp_ffi_js/ir/StreamReader.cpp
@@ -129,6 +129,7 @@ EMSCRIPTEN_BINDINGS(ClpStreamReader) {
             "Array<[string, bigint, number, number]>"
     );
     emscripten::register_type<clp_ffi_js::ir::FilteredLogEventMapTsType>("number[] | null");
+    emscripten::register_type<clp_ffi_js::ir::LogEventIdxTsType>("number | null");
     emscripten::class_<clp_ffi_js::ir::StreamReader>("ClpStreamReader")
             .constructor(
                     &clp_ffi_js::ir::StreamReader::create,
@@ -148,7 +149,7 @@ EMSCRIPTEN_BINDINGS(ClpStreamReader) {
             .function("decodeRange", &clp_ffi_js::ir::StreamReader::decode_range)
             .function(
                     "getLogEventIndexByTimestamp",
-                    &clp_ffi_js::ir::StreamReader::find_timestamp_last_occurrence
+                    &clp_ffi_js::ir::StreamReader::get_log_event_index_by_timestamp
             );
 }
 }  // namespace
diff --git a/src/clp_ffi_js/ir/StreamReader.hpp b/src/clp_ffi_js/ir/StreamReader.hpp
index 9ce68d32..ad9a9c7f 100644
--- a/src/clp_ffi_js/ir/StreamReader.hpp
+++ b/src/clp_ffi_js/ir/StreamReader.hpp
@@ -5,7 +5,7 @@
 #include <concepts>
 #include <cstddef>
 #include <cstdint>
-#include <ir/types.hpp>
+#include <clp/ir/types.hpp>
 #include <memory>
 #include <optional>
 #include <string>
@@ -30,6 +30,7 @@ EMSCRIPTEN_DECLARE_VAL_TYPE(ReaderOptions);
 // JS types used as outputs
 EMSCRIPTEN_DECLARE_VAL_TYPE(DecodedResultsTsType);
 EMSCRIPTEN_DECLARE_VAL_TYPE(FilteredLogEventMapTsType);
+EMSCRIPTEN_DECLARE_VAL_TYPE(LogEventIdxTsType);
 
 enum class StreamType : uint8_t {
     Structured,
@@ -124,10 +125,15 @@ class StreamReader {
      */
     [[nodiscard]] virtual auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType = 0;
-
-    [[nodiscard]] virtual auto find_timestamp_last_occurrence(
-            clp::ir::epoch_time_ms_t input_timestamp
-    ) -> std::ptrdiff_t = 0;
+    /**
+     * Retrieves the last index of the log event that matches the given timestamp.
+     *
+     * @param timestamp The timestamp to search for, in milliseconds since the Unix epoch.
+     * @return The index of the log event with the specified timestamp, or null value if not found.
+     */
+    [[nodiscard]] virtual auto get_log_event_index_by_timestamp(
+            clp::ir::epoch_time_ms_t timestamp
+    ) -> LogEventIdxTsType = 0;
 
 protected:
     explicit StreamReader() = default;
diff --git a/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp b/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
index 36832845..04b4c0f2 100644
--- a/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
+++ b/src/clp_ffi_js/ir/StructuredIrStreamReader.cpp
@@ -147,28 +147,27 @@ auto StructuredIrStreamReader::decode_range(size_t begin_idx, size_t end_idx, bo
     );
 }
 
-auto StructuredIrStreamReader::find_timestamp_last_occurrence(
-        clp::ir::epoch_time_ms_t input_timestamp
-) -> std::ptrdiff_t {
-    // Use std::lower_bound with a custom comparator
+auto StructuredIrStreamReader::get_log_event_index_by_timestamp(
+        clp::ir::epoch_time_ms_t timestamp
+) -> LogEventIdxTsType {
     auto it = std::lower_bound(
             m_deserialized_log_events->begin(),
             m_deserialized_log_events->end(),
-            input_timestamp,
+            timestamp,
             [](const LogEventWithFilterData<StructuredLogEvent>& event, clp::ir::epoch_time_ms_t timestamp) {
                 return event.get_timestamp() <= timestamp;
             }
     );
 
     // Adjust the iterator to find the last valid index
-    if (it == m_deserialized_log_events->end() || it->get_timestamp() > input_timestamp) {
+    if (it == m_deserialized_log_events->end() || it->get_timestamp() > timestamp) {
         if (it == m_deserialized_log_events->begin()) {
-            return -1;  // No element satisfies the condition
+            return LogEventIdxTsType{emscripten::val::null()};
         }
         --it;
     }
 
-    return std::distance(m_deserialized_log_events->begin(), it);
+    return LogEventIdxTsType{emscripten::val(std::distance(m_deserialized_log_events->begin(), it))};
 }
 
 StructuredIrStreamReader::StructuredIrStreamReader(
diff --git a/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp b/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
index 1af21d96..28a68a0e 100644
--- a/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
+++ b/src/clp_ffi_js/ir/StructuredIrStreamReader.hpp
@@ -8,6 +8,7 @@
 #include <clp/Array.hpp>
 #include <clp/ffi/ir_stream/Deserializer.hpp>
 #include <clp/ffi/SchemaTree.hpp>
+#include <clp/ir/types.hpp>
 #include <emscripten/val.h>
 
 #include <clp_ffi_js/ir/LogEventWithFilterData.hpp>
@@ -74,8 +75,8 @@ class StructuredIrStreamReader : public StreamReader {
     [[nodiscard]] auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType override;
 
-    [[nodiscard]] auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp
-    ) -> std::ptrdiff_t override;
+    [[nodiscard]] auto get_log_event_index_by_timestamp(clp::ir::epoch_time_ms_t timestamp
+    ) -> LogEventIdxTsType override;
 
 private:
     // Constructor
diff --git a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
index 5e0994f4..42574113 100644
--- a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
+++ b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.cpp
@@ -158,9 +158,9 @@ auto UnstructuredIrStreamReader::decode_range(size_t begin_idx, size_t end_idx,
     );
 }
 
-auto UnstructuredIrStreamReader::find_timestamp_last_occurrence(
+auto UnstructuredIrStreamReader::get_log_event_index_by_timestamp(
         clp::ir::epoch_time_ms_t input_timestamp
-) -> std::ptrdiff_t {
+) -> LogEventIdxTsType {
     // Use std::lower_bound with a custom comparator
     auto it = std::lower_bound(
             m_encoded_log_events.begin(),
@@ -173,12 +173,12 @@ auto UnstructuredIrStreamReader::find_timestamp_last_occurrence(
     // Adjust the iterator to find the last valid index
     if (it == m_encoded_log_events.end() || it->get_timestamp() > input_timestamp) {
         if (it == m_encoded_log_events.begin()) {
-            return -1;  // No element satisfies the condition
+            return LogEventIdxTsType{emscripten::val::null()};
         }
         --it;
     }
 
-    return std::distance(m_encoded_log_events.begin(), it);
+    return LogEventIdxTsType{emscripten::val(std::distance(m_encoded_log_events.begin(), it))};
 }
 
 UnstructuredIrStreamReader::UnstructuredIrStreamReader(
diff --git a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
index 3fffdf6c..d6298615 100644
--- a/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
+++ b/src/clp_ffi_js/ir/UnstructuredIrStreamReader.hpp
@@ -71,8 +71,8 @@ class UnstructuredIrStreamReader : public StreamReader {
     [[nodiscard]] auto decode_range(size_t begin_idx, size_t end_idx, bool use_filter) const
             -> DecodedResultsTsType override;
 
-    [[nodiscard]] auto find_timestamp_last_occurrence(clp::ir::epoch_time_ms_t input_timestamp
-    ) -> std::ptrdiff_t override;
+    [[nodiscard]] auto get_log_event_index_by_timestamp(clp::ir::epoch_time_ms_t input_timestamp
+    ) -> LogEventIdxTsType override;
 
 private:
     // Constructor