Add foundation logging facade

src/foundation/log.h

@@ -0,0 +1,67 @@
+#pragma once
+
+#include "foundation/result.h"
+
+#include <cstdint>
+#include <string>
+#include <string_view>
+#include <vector>
+
+namespace pp::foundation {
+
+enum class LogLevel : std::uint8_t {
+    trace,
+    debug,
+    info,
+    warning,
+    error,
+};
+
+struct LogRecord {
+    LogLevel level = LogLevel::info;
+    std::string component;
+    std::string message;
+    std::uint64_t frame_id = 0;
+    std::uint64_t stroke_id = 0;
+    std::uint64_t thread_id = 0;
+};
+
+class ILogSink {
+public:
+    virtual ~ILogSink() = default;
+    virtual void write(const LogRecord& record) noexcept = 0;
+};
+
+class Logger {
+public:
+    explicit Logger(ILogSink& sink) noexcept;
+
+    void set_min_level(LogLevel level) noexcept;
+    [[nodiscard]] LogLevel min_level() const noexcept;
+
+    [[nodiscard]] Status write(
+        LogLevel level,
+        std::string_view component,
+        std::string_view message,
+        std::uint64_t frame_id = 0,
+        std::uint64_t stroke_id = 0,
+        std::uint64_t thread_id = 0) noexcept;
+
+private:
+    ILogSink* sink_ = nullptr;
+    LogLevel min_level_ = LogLevel::trace;
+};
+
+class MemoryLogSink final : public ILogSink {
+public:
+    void write(const LogRecord& record) noexcept override;
+    [[nodiscard]] const std::vector<LogRecord>& records() const noexcept;
+    void clear() noexcept;
+
+private:
+    std::vector<LogRecord> records_;
+};
+
+[[nodiscard]] const char* log_level_name(LogLevel level) noexcept;
+
+}