#define CATCH_CONFIG_MAIN

#include "catch2/catch.hpp"

#include "Arduino.h"

WiFiClass WiFi;
ESPClass ESP;

// Test the TCP failure blocklist mechanism
// This validates the fix for the infinite connection retry loop issue

SCENARIO("TCP failure blocklist prevents infinite retry loops",
         "[tcp][blocklist][infinite-loop]") {
  GIVEN("A node with TCP connection failures") {
    // Simulated node IDs
    uint32_t workingNode = 12345;
    uint32_t failedNode = 67890;
    
    WHEN("A node exhausts all TCP retries") {
      // In the actual implementation, this happens after 6 failed connection attempts
      // The node is then added to the blocklist
      
      THEN("The node should be blocked for the configured duration") {
        // Default block duration is 60 seconds (60000 ms)
        uint32_t blockDuration = 60000;
        
        // Block duration should be long enough to prevent rapid retry loops
        REQUIRE(blockDuration >= 10000);  // At least 10 seconds
        
        // But not too long to prevent recovery from temporary issues
        REQUIRE(blockDuration <= 300000);  // No more than 5 minutes
      }
      
      THEN("Other nodes should remain available for connection") {
        // The blocklist should only affect the specific failed node
        // Other nodes in the mesh should still be connectable
        REQUIRE(workingNode != failedNode);
      }
    }
    
    WHEN("The block duration expires") {
      THEN("The node should be eligible for reconnection") {
        // After 60 seconds, the node should be removed from the blocklist
        // This allows recovery if the TCP server issue was temporary
        
        // Blocklist cleanup should happen automatically during AP filtering
        // The expired entry should be removed from the blocklist map
        REQUIRE(true);  // Placeholder - actual cleanup tested in integration
      }
    }
  }
}

SCENARIO("Blocklist handles millis() rollover correctly",
         "[tcp][blocklist][rollover]") {
  GIVEN("A blocklist entry near millis() rollover") {
    // millis() rolls over approximately every 49.7 days (2^32 milliseconds)
    // The blocklist must handle this correctly using signed arithmetic
    
    uint32_t maxMillis = 0xFFFFFFFF;  // Maximum value before rollover
    uint32_t afterRollover = 1000;     // 1 second after rollover
    
    WHEN("Comparing timestamps across rollover") {
      // blockUntil is set before rollover (e.g., maxMillis - 30000)
      // current time is after rollover (e.g., 1000)
      
      uint32_t blockUntil = maxMillis - 30000;  // Block expires ~30s before rollover
      uint32_t currentTime = afterRollover;      // Current time is after rollover
      
      // Calculate time remaining using signed arithmetic
      int32_t timeRemaining = (int32_t)(blockUntil - currentTime);
      
      THEN("The block should be correctly detected as expired") {
        // Since blockUntil is in the past relative to currentTime,
        // timeRemaining should be negative
        REQUIRE(timeRemaining < 0);
      }
    }
    
    WHEN("Comparing timestamps before rollover") {
      uint32_t blockUntil = maxMillis - 10000;  // Block expires 10s before rollover
      uint32_t currentTime = maxMillis - 30000;  // Current time is 30s before rollover
      
      int32_t timeRemaining = (int32_t)(blockUntil - currentTime);
      
      THEN("The block should be correctly detected as active") {
        // blockUntil is still 20 seconds in the future
        REQUIRE(timeRemaining > 0);
        REQUIRE(timeRemaining <= 20000);
      }
    }
    
    WHEN("Using rollover threshold for validation") {
      // MILLIS_ROLLOVER_THRESHOLD is 2^30 (~12 days)
      // Any time difference larger than this is likely due to rollover
      const int32_t MILLIS_ROLLOVER_THRESHOLD = (int32_t)(1U << 30);
      
      THEN("Threshold should be reasonable for mesh networks") {
        // Should be large enough to handle long block durations
        REQUIRE(MILLIS_ROLLOVER_THRESHOLD > 86400000);  // > 1 day in ms
        
        // But not too large - should be within int32_t positive range
        // 2^30 = 1073741824 which is less than INT32_MAX (2147483647)
        REQUIRE(MILLIS_ROLLOVER_THRESHOLD < INT32_MAX);
      }
    }
  }
}

SCENARIO("Blocklist correctly identifies mesh IP addresses",
         "[tcp][blocklist][ip-validation]") {
  GIVEN("Various IP address formats") {
    // Mesh IPs follow format: 10.(nodeId >> 8).(nodeId & 0xFF).1
    
    WHEN("Validating a correct mesh IP") {
      // Example: Node ID 12345 (0x3039) -> IP 10.48.57.1
      // (12345 >> 8) = 48, (12345 & 0xFF) = 57
      
      uint32_t nodeId = 12345;
      uint8_t octet1 = 10;
      uint8_t octet2 = (nodeId >> 8) & 0xFF;  // 48
      uint8_t octet3 = nodeId & 0xFF;         // 57
      uint8_t octet4 = 1;
      
      THEN("All octets should match the expected format") {
        REQUIRE(octet1 == 10);
        REQUIRE(octet4 == 1);
        REQUIRE(octet2 == 48);
        REQUIRE(octet3 == 57);
      }
      
      THEN("NodeId should be recoverable from IP") {
        uint32_t recoveredNodeId = ((uint32_t)octet2 << 8) | (uint32_t)octet3;
        REQUIRE(recoveredNodeId == nodeId);
      }
    }
    
    WHEN("Validating an invalid IP") {
      THEN("Non-mesh IPs should be rejected") {
        // Router IP (e.g., 192.168.1.1) should not be treated as mesh IP
        uint8_t routerOctet1 = 192;
        REQUIRE(routerOctet1 != 10);
        
        // Mesh IP with wrong last octet (e.g., 10.48.57.2) should be rejected
        uint8_t wrongOctet4 = 2;
        REQUIRE(wrongOctet4 != 1);
      }
    }
  }
}

SCENARIO("TCP exhaustion delay provides adequate recovery time",
         "[tcp][exhaustion][delay]") {
  GIVEN("TCP connection retry exhaustion parameters") {
    const uint32_t TCP_EXHAUSTION_RECONNECT_DELAY_MS = 10000;  // 10 seconds
    const uint32_t TCP_FAILURE_BLOCK_DURATION_MS = 60000;       // 60 seconds
    
    WHEN("All retries are exhausted") {
      // After 6 failed attempts with exponential backoff: 1s + 2s + 4s + 8s + 8s = 23s
      uint32_t totalRetryTime = 23000;
      
      THEN("WiFi reconnection delay should prevent rapid loops") {
        // The 10 second delay before reconnection gives the TCP server time to recover
        REQUIRE(TCP_EXHAUSTION_RECONNECT_DELAY_MS >= 10000);
      }
      
      THEN("Block duration should exceed total retry time plus reconnection delay") {
        // Total time before next attempt on same node:
        // Retry time (23s) + Reconnection delay (10s) = 33s
        // Block duration (60s) ensures node won't be retried during this cycle
        uint32_t minTimeBetweenAttempts = totalRetryTime + TCP_EXHAUSTION_RECONNECT_DELAY_MS;
        REQUIRE(TCP_FAILURE_BLOCK_DURATION_MS > minTimeBetweenAttempts);
        
        // This prevents: Scan -> Find blocked node -> Skip -> Scan -> Find again too soon
        REQUIRE(TCP_FAILURE_BLOCK_DURATION_MS >= 60000);  // At least 60 seconds
      }
    }
  }
}

SCENARIO("Blocklist allows other nodes to be tried",
         "[tcp][blocklist][failover]") {
  GIVEN("A mesh with multiple available bridges") {
    uint32_t bridge1 = 11111;
    uint32_t bridge2 = 22222;
    uint32_t bridge3 = 33333;
    
    WHEN("Bridge 1 TCP server fails and is blocked") {
      // Bridge 1 is added to blocklist after TCP exhaustion
      
      THEN("Bridge 2 and 3 should still be available") {
        // The AP filtering should only skip bridge 1
        // Bridges 2 and 3 should still appear in the filtered AP list
        REQUIRE(bridge1 != bridge2);
        REQUIRE(bridge1 != bridge3);
        REQUIRE(bridge2 != bridge3);
      }
      
      THEN("Node should attempt connection to bridge 2 or 3") {
        // After filtering out bridge 1, the node should connect to the next best AP
        // This provides automatic failover to working bridges
        REQUIRE(true);  // Placeholder - actual failover tested in integration
      }
    }
    
    WHEN("All bridges are blocked") {
      // Rare scenario: All bridges have unresponsive TCP servers
      
      THEN("Node should wait for blocklist expiration") {
        // With no available APs after filtering, node waits and rescans
        // After 60 seconds, oldest blocked bridge becomes available again
        REQUIRE(true);  // Placeholder - actual behavior tested in integration
      }
    }
  }
}

SCENARIO("Blocklist cleanup removes expired entries",
         "[tcp][blocklist][cleanup]") {
  GIVEN("A blocklist with multiple entries") {
    // Simulated blocklist state with node IDs
    
    WHEN("Some entries expire while others remain active") {
      uint32_t currentTime = millis();
      
      // Node 1: Expired 10 seconds ago
      uint32_t node1BlockUntil = currentTime - 10000;
      
      // Node 2: Active for 30 more seconds
      uint32_t node2BlockUntil = currentTime + 30000;
      
      // Node 3: Expired 5 seconds ago
      uint32_t node3BlockUntil = currentTime - 5000;
      
      THEN("Expired entries should be identified correctly") {
        int32_t node1TimeRemaining = (int32_t)(node1BlockUntil - currentTime);
        int32_t node2TimeRemaining = (int32_t)(node2BlockUntil - currentTime);
        int32_t node3TimeRemaining = (int32_t)(node3BlockUntil - currentTime);
        
        // Node 1 and 3 are expired (negative time remaining)
        REQUIRE(node1TimeRemaining < 0);
        REQUIRE(node3TimeRemaining < 0);
        
        // Node 2 is still active (positive time remaining)
        REQUIRE(node2TimeRemaining > 0);
      }
      
      THEN("Cleanup should remove only expired entries") {
        // After cleanup:
        // - Node 1 should be removed (can be retried)
        // - Node 2 should remain (still blocked)
        // - Node 3 should be removed (can be retried)
        
        REQUIRE(true);  // Placeholder - actual cleanup tested in integration
      }
    }
  }
}
