platform_metrics_example.cpp

// BSD 3-Clause License
// Copyright (c) 2021-2025, 🍀☀🌕🌥 🌊
// See the LICENSE file in the project root for full license information.

/**
 * @file platform_metrics_example.cpp
 * @brief Demonstrates platform_metrics_collector usage
 * @example platform_metrics_example.cpp
 *
 * This example shows how to use the unified platform metrics collector:
 * - platform_metrics_collector initialization
 * - Platform-specific metric access patterns
 * - Strategy pattern usage for OS abstraction
 * - Handling platform-specific features gracefully
 * - Cross-platform metric normalization
 */

#include <iostream>
#include <thread>
#include <chrono>
#include <iomanip>

#include "kcenon/monitoring/collectors/platform_metrics_collector.h"

using namespace kcenon::monitoring;
using namespace std::chrono_literals;

/**
 * Display platform information
 */
void display_platform_info(const platform_info& info) {
    std::cout << "\n=== Platform Information ===" << std::endl;

    if (info.available) {
        std::cout << "Platform: " << info.name << std::endl;
        std::cout << "Version: " << info.version << std::endl;
        std::cout << "Architecture: " << info.architecture << std::endl;
    } else {
        std::cout << "Platform information not available" << std::endl;
    }
}

/**
 * Display uptime metrics
 */
void display_uptime_metrics(const platform_uptime& uptime) {
    std::cout << "\n=== Uptime Metrics ===" << std::endl;

    if (uptime.available) {
        // Convert seconds to days, hours, minutes
        int64_t seconds = uptime.uptime_seconds;
        int64_t days = seconds / (24 * 3600);
        seconds %= (24 * 3600);
        int64_t hours = seconds / 3600;
        seconds %= 3600;
        int64_t minutes = seconds / 60;
        seconds %= 60;

        std::cout << "System Uptime: " << days << "d " << hours << "h "
                  << minutes << "m " << seconds << "s" << std::endl;
        std::cout << "Total Uptime: " << uptime.uptime_seconds << " seconds" << std::endl;
        std::cout << "Idle Time: " << uptime.idle_seconds << " seconds" << std::endl;

        // Display boot timestamp as ISO 8601 format if available
        if (uptime.boot_timestamp > 0) {
            auto boot_time = std::chrono::system_clock::from_time_t(uptime.boot_timestamp);
            auto boot_tt = std::chrono::system_clock::to_time_t(boot_time);
            std::tm boot_tm{};
#ifdef _MSC_VER
            localtime_s(&boot_tm, &boot_tt);
#else
            localtime_r(&boot_tt, &boot_tm);
#endif
            std::cout << "Boot Time: " << std::put_time(&boot_tm, "%Y-%m-%d %H:%M:%S") << std::endl;
        }
    } else {
        std::cout << "Uptime metrics not available on this platform" << std::endl;
    }
}

/**
 * Display context switch statistics
 */
void display_context_switch_stats(const platform_context_switches& switches) {
    std::cout << "\n=== Context Switch Statistics ===" << std::endl;

    if (switches.available) {
        std::cout << "Total Switches: " << switches.total_switches << std::endl;
        std::cout << "Voluntary Switches: " << switches.voluntary_switches << std::endl;
        std::cout << "Involuntary Switches: " << switches.involuntary_switches << std::endl;
        std::cout << "Switches Per Second: " << std::fixed << std::setprecision(2)
                  << switches.switches_per_second << std::endl;
    } else {
        std::cout << "Context switch statistics not available on this platform" << std::endl;
    }
}

/**
 * Display TCP connection state information
 */
void display_tcp_info(const platform_tcp_info& tcp) {
    std::cout << "\n=== TCP Connection States ===" << std::endl;

    if (tcp.available) {
        std::cout << "ESTABLISHED: " << tcp.established << std::endl;
        std::cout << "SYN_SENT: " << tcp.syn_sent << std::endl;
        std::cout << "SYN_RECV: " << tcp.syn_recv << std::endl;
        std::cout << "FIN_WAIT1: " << tcp.fin_wait1 << std::endl;
        std::cout << "FIN_WAIT2: " << tcp.fin_wait2 << std::endl;
        std::cout << "TIME_WAIT: " << tcp.time_wait << std::endl;
        std::cout << "CLOSE_WAIT: " << tcp.close_wait << std::endl;
        std::cout << "LISTEN: " << tcp.listen << std::endl;
        std::cout << "Total Connections: " << tcp.total << std::endl;
    } else {
        std::cout << "TCP state information not available on this platform" << std::endl;
    }
}

/**
 * Display socket buffer information
 */
void display_socket_info(const platform_socket_info& socket) {
    std::cout << "\n=== Socket Buffer Information ===" << std::endl;

    if (socket.available) {
        std::cout << "RX Buffer Size: " << (socket.rx_buffer_size / 1024.0) << " KB" << std::endl;
        std::cout << "TX Buffer Size: " << (socket.tx_buffer_size / 1024.0) << " KB" << std::endl;
        std::cout << "RX Buffer Used: " << (socket.rx_buffer_used / 1024.0) << " KB ("
                  << std::fixed << std::setprecision(1)
                  << (socket.rx_buffer_size > 0 ? (socket.rx_buffer_used * 100.0 / socket.rx_buffer_size) : 0.0)
                  << "%)" << std::endl;
        std::cout << "TX Buffer Used: " << (socket.tx_buffer_used / 1024.0) << " KB ("
                  << (socket.tx_buffer_size > 0 ? (socket.tx_buffer_used * 100.0 / socket.tx_buffer_size) : 0.0)
                  << "%)" << std::endl;
    } else {
        std::cout << "Socket buffer information not available on this platform" << std::endl;
    }
}

/**
 * Display interrupt statistics
 */
void display_interrupt_info(const platform_interrupt_info& interrupts) {
    std::cout << "\n=== Interrupt Statistics ===" << std::endl;

    if (interrupts.available) {
        std::cout << "Total Interrupts: " << interrupts.total_interrupts << std::endl;
    } else {
        std::cout << "Interrupt statistics not available on this platform" << std::endl;
    }
}

/**
 * Demonstrate platform-specific feature detection and handling
 */
void demonstrate_platform_features(platform_metrics_collector& collector) {
    std::cout << "\n=== Platform-Specific Feature Detection ===" << std::endl;

    // Collect platform info first
    auto info = collector.get_platform_info();

    std::cout << "\nDetected Platform: " << info.name << std::endl;

    // Demonstrate feature availability checks before collection
    std::cout << "\nFeature Availability:" << std::endl;

    // Display feature availability
    std::cout << "  Platform Available: " << (collector.is_platform_available() ? "Yes" : "No") << std::endl;
    std::cout << "  Collector Health: " << (collector.is_available() ? "Healthy" : "Unhealthy") << std::endl;

    std::cout << "\nNote: The Strategy pattern abstracts platform-specific implementations." << std::endl;
    std::cout << "      Features not supported on a platform return empty/unavailable values." << std::endl;

#if defined(__linux__)
    std::cout << "\nLinux-specific features:" << std::endl;
    std::cout << "  - Reading /proc/stat for context switches" << std::endl;
    std::cout << "  - Reading /proc/net/tcp for TCP state info" << std::endl;
    std::cout << "  - Reading /proc/uptime for system uptime" << std::endl;
#elif defined(__APPLE__)
    std::cout << "\nmacOS-specific features:" << std::endl;
    std::cout << "  - Using sysctl for system metrics" << std::endl;
    std::cout << "  - Limited TCP state information" << std::endl;
    std::cout << "  - Using kern.boottime for uptime" << std::endl;
#elif defined(_WIN32)
    std::cout << "\nWindows-specific features:" << std::endl;
    std::cout << "  - Using GetTickCount64 for uptime" << std::endl;
    std::cout << "  - Using Performance Counters for metrics" << std::endl;
    std::cout << "  - Limited context switch information" << std::endl;
#else
    std::cout << "\nUnknown platform - limited feature support" << std::endl;
#endif
}

/**
 * Demonstrate cross-platform metric normalization
 */
void demonstrate_metric_normalization(const std::vector<metric>& metrics) {
    std::cout << "\n=== Cross-Platform Metric Normalization ===" << std::endl;

    std::cout << "\nAll metrics use standardized naming conventions:" << std::endl;
    std::cout << "  platform.uptime.* - Uptime metrics" << std::endl;
    std::cout << "  platform.context_switches.* - Context switch metrics" << std::endl;
    std::cout << "  platform.tcp.* - TCP state metrics" << std::endl;
    std::cout << "  platform.socket.* - Socket buffer metrics" << std::endl;
    std::cout << "  platform.interrupts.* - Interrupt metrics" << std::endl;

    std::cout << "\nCollected Metrics (" << metrics.size() << " total):" << std::endl;

    // Display metrics directly without grouping to avoid compilation issues
    for (const auto& m : metrics) {
        std::cout << "  " << m.name << ": ";
        std::visit([](const auto& val) { std::cout << val; }, m.value);
        auto unit_it = m.tags.find("unit");
        if (unit_it != m.tags.end() && !unit_it->second.empty()) {
            std::cout << " " << unit_it->second;
        }
        std::cout << std::endl;
    }
}

int main() {
    std::cout << "=== Platform Metrics Example ===" << std::endl;

    try {
        // Step 1: Create platform_metrics_collector with configuration
        std::cout << "\n1. Creating platform_metrics_collector..." << std::endl;

        platform_metrics_config config;
        config.collect_uptime = true;
        config.collect_context_switches = true;
        config.collect_tcp_states = true;
        config.collect_socket_buffers = true;
        config.collect_interrupts = true;

        platform_metrics_collector collector(config);

        // Initialize the collector
        std::unordered_map<std::string, std::string> init_config;
        if (!collector.initialize(init_config)) {
            std::cerr << "Failed to initialize platform_metrics_collector" << std::endl;
            return 1;
        }

        std::cout << "   Initialized: " << collector.name() << std::endl;
        std::cout << "   Health: " << (collector.is_available() ? "OK" : "UNHEALTHY") << std::endl;

        // Step 2: Display platform information
        std::cout << "\n2. Retrieving platform information..." << std::endl;
        auto platform_info = collector.get_platform_info();
        display_platform_info(platform_info);

        // Step 3: Demonstrate platform-specific feature detection
        std::cout << "\n3. Demonstrating platform-specific features..." << std::endl;
        demonstrate_platform_features(collector);

        // Step 4: Collect and display metrics (3 iterations)
        std::cout << "\n4. Collecting platform metrics (3 iterations)..." << std::endl;

        for (int i = 0; i < 3; ++i) {
            std::cout << "\n--- Iteration " << (i + 1) << "/3 ---" << std::endl;

            // Collect all platform metrics
            auto metrics = collector.collect();
            std::cout << "Metrics collected: " << metrics.size() << std::endl;

            // Get last collected metrics for detailed display
            auto last_metrics = collector.get_last_metrics();

            // Display each metric category
            display_uptime_metrics(last_metrics.uptime);
            display_context_switch_stats(last_metrics.context_switches);
            display_tcp_info(last_metrics.tcp);
            display_socket_info(last_metrics.socket);
            display_interrupt_info(last_metrics.interrupts);

            // Wait before next collection
            if (i < 2) {
                std::cout << "\nWaiting 2 seconds before next collection..." << std::endl;
                std::this_thread::sleep_for(2s);
            }
        }

        // Step 5: Demonstrate metric normalization
        std::cout << "\n5. Demonstrating cross-platform metric normalization..." << std::endl;
        auto final_metrics = collector.collect();
        demonstrate_metric_normalization(final_metrics);

        // Step 6: Display collector statistics
        std::cout << "\n6. Collector Statistics:" << std::endl;

        auto stats = collector.get_statistics();
        for (const auto& [key, value] : stats) {
            std::cout << "  " << key << ": " << value << std::endl;
        }

        // Step 7: Demonstrate dynamic configuration updates
        std::cout << "\n7. Configuration note:" << std::endl;
        std::cout << "   Platform metrics collector configuration is set at initialization." << std::endl;
        std::cout << "   To change configuration, recreate the collector with new config." << std::endl;

        std::cout << "\n=== Example completed successfully ===" << std::endl;

    } catch (const std::exception& e) {
        std::cerr << "Exception: " << e.what() << std::endl;
        return 1;
    }

    return 0;
}