#include "AuthService.h"
#include "DatabaseService.h"
#include "RedisHelper.h"
#include <drogon/utils/Utilities.h>
#include <regex>
#include <random>
#include <functional>
#include <memory>
#include <fstream>
#include <sstream>
#include <cstdlib>
#include <gpgme.h>
#include <filesystem>

using namespace drogon;
using namespace drogon::orm;

bool AuthService::validatePassword(const std::string& password, std::string& error) {
    if (password.length() < 8) {
        error = "Password must be at least 8 characters long";
        return false;
    }
    
    if (!std::regex_search(password, std::regex("[0-9]"))) {
        error = "Password must contain at least one number";
        return false;
    }
    
    if (!std::regex_search(password, std::regex("[!@#$%^&*(),.?\":{}|<>]"))) {
        error = "Password must contain at least one symbol";
        return false;
    }
    
    return true;
}

// GPGME-based PGP signature verification (no shell commands for security)
namespace {
    // RAII wrapper for gpgme_data_t (named to avoid conflict with deprecated GpgmeData typedef)
    class GpgmeDataWrapper {
    public:
        GpgmeDataWrapper() : data_(nullptr) {}
        ~GpgmeDataWrapper() { if (data_) gpgme_data_release(data_); }
        gpgme_data_t* ptr() { return &data_; }
        gpgme_data_t get() { return data_; }
        bool valid() const { return data_ != nullptr; }
    private:
        gpgme_data_t data_;
    };

    // RAII wrapper for gpgme_ctx_t
    class GpgmeContextWrapper {
    public:
        GpgmeContextWrapper() : ctx_(nullptr) {}
        ~GpgmeContextWrapper() { if (ctx_) gpgme_release(ctx_); }
        gpgme_ctx_t* ptr() { return &ctx_; }
        gpgme_ctx_t get() { return ctx_; }
        bool valid() const { return ctx_ != nullptr; }
    private:
        gpgme_ctx_t ctx_;
    };
}

bool verifyPgpSignature(const std::string& message, const std::string& signature, const std::string& publicKey) {
    try {
        // Initialize GPGME
        gpgme_check_version(nullptr);

        // Create temporary directory for isolated keyring using filesystem
        std::string tmpDir = "/tmp/pgp_verify_" + drogon::utils::genRandomString(16);
        std::filesystem::create_directories(tmpDir);
        std::filesystem::permissions(tmpDir, std::filesystem::perms::owner_all);

        // Set GNUPGHOME environment for this context
        std::string gnupgHome = tmpDir;

        // Create GPGME context
        GpgmeContextWrapper ctx;
        gpgme_error_t err = gpgme_new(ctx.ptr());
        if (err) {
            LOG_ERROR << "Failed to create GPGME context: " << gpgme_strerror(err);
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        // Set the engine info to use our temporary directory
        err = gpgme_ctx_set_engine_info(ctx.get(), GPGME_PROTOCOL_OpenPGP, nullptr, gnupgHome.c_str());
        if (err) {
            LOG_ERROR << "Failed to set GPGME engine info: " << gpgme_strerror(err);
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        // Set protocol
        gpgme_set_protocol(ctx.get(), GPGME_PROTOCOL_OpenPGP);

        // Import the public key
        GpgmeDataWrapper keyData;
        err = gpgme_data_new_from_mem(keyData.ptr(), publicKey.c_str(), publicKey.size(), 1);
        if (err) {
            LOG_ERROR << "Failed to create key data: " << gpgme_strerror(err);
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        err = gpgme_op_import(ctx.get(), keyData.get());
        if (err) {
            LOG_ERROR << "Failed to import public key: " << gpgme_strerror(err);
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        gpgme_import_result_t importResult = gpgme_op_import_result(ctx.get());
        if (!importResult || (importResult->imported == 0 && importResult->unchanged == 0)) {
            LOG_ERROR << "No keys were imported";
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        LOG_DEBUG << "GPGME imported " << importResult->imported << " keys, "
                  << importResult->unchanged << " unchanged";

        // Create data objects for signature and message
        GpgmeDataWrapper sigData;
        err = gpgme_data_new_from_mem(sigData.ptr(), signature.c_str(), signature.size(), 1);
        if (err) {
            LOG_ERROR << "Failed to create signature data: " << gpgme_strerror(err);
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        GpgmeDataWrapper msgData;
        err = gpgme_data_new_from_mem(msgData.ptr(), message.c_str(), message.size(), 1);
        if (err) {
            LOG_ERROR << "Failed to create message data: " << gpgme_strerror(err);
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        // Verify the signature
        err = gpgme_op_verify(ctx.get(), sigData.get(), msgData.get(), nullptr);
        if (err) {
            LOG_WARN << "Signature verification failed: " << gpgme_strerror(err);
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        // Check verification result
        gpgme_verify_result_t verifyResult = gpgme_op_verify_result(ctx.get());
        if (!verifyResult || !verifyResult->signatures) {
            LOG_WARN << "No signatures found in verification result";
            std::filesystem::remove_all(tmpDir);
            return false;
        }

        // Check if signature is valid
        gpgme_signature_t sig = verifyResult->signatures;
        bool verified = (sig->status == GPG_ERR_NO_ERROR);

        if (verified) {
            LOG_INFO << "Signature verification successful for challenge";
        } else {
            LOG_WARN << "Signature verification failed: " << gpgme_strerror(sig->status);
        }

        // Cleanup temporary directory
        std::filesystem::remove_all(tmpDir);

        return verified;

    } catch (const std::exception& e) {
        LOG_ERROR << "Exception during signature verification: " << e.what();
        return false;
    }
}

void AuthService::generateUniqueColor(std::function<void(const std::string& color)> callback) {
    try {
        auto dbClient = app().getDbClient();
        
        // Create a structure to hold the state for recursive attempts
        struct ColorGenerator : public std::enable_shared_from_this<ColorGenerator> {
            std::mt19937 gen;
            std::uniform_int_distribution<> dis;
            std::function<void(const std::string&)> callback;
            DbClientPtr dbClient;
            int attempts;
            
            ColorGenerator(std::function<void(const std::string&)> cb, DbClientPtr db) 
                : gen(std::random_device{}()), 
                  dis(0, 0xFFFFFF),
                  callback(cb),
                  dbClient(db),
                  attempts(0) {}
            
            void tryGenerate() {
                auto self = shared_from_this();
                
                // Limit attempts to prevent infinite recursion
                if (++attempts > 100) {
                    LOG_ERROR << "Failed to generate unique color after 100 attempts";
                    callback("#561D5E");  // Fallback to default
                    return;
                }
                
                // Generate random color
                int colorValue = dis(gen);
                char colorHex[8];
                snprintf(colorHex, sizeof(colorHex), "#%06X", colorValue);
                std::string color(colorHex);
                
                // Check if color exists
                *dbClient << "SELECT id FROM users WHERE user_color = $1 LIMIT 1"
                          << color
                          >> [self, color](const Result& r) {
                              if (r.empty()) {
                                  // Color is unique, use it
                                  self->callback(color);
                              } else {
                                  // Color exists, try again
                                  self->tryGenerate();
                              }
                          }
                          >> [self](const DrogonDbException& e) {
                              LOG_ERROR << "Database error checking color: " << e.base().what();
                              // Fallback to a default color
                              self->callback("#561D5E");
                          };
            }
        };
        
        auto generator = std::make_shared<ColorGenerator>(callback, dbClient);
        generator->tryGenerate();
        
    } catch (const std::exception& e) {
        LOG_ERROR << "Exception in generateUniqueColor: " << e.what();
        callback("#561D5E");  // Fallback to default
    }
}

void AuthService::updateUserColor(int64_t userId, const std::string& newColor,
                                 std::function<void(bool, const std::string&, const std::string&)> callback) {
    try {
        // Validate color format
        if (newColor.length() != 7 || newColor[0] != '#') {
            callback(false, "Invalid color format. Use #RRGGBB", "");
            return;
        }
        
        // Check if color is valid hex
        for (size_t i = 1; i < 7; i++) {
            if (!std::isxdigit(newColor[i])) {
                callback(false, "Invalid color format. Use #RRGGBB", "");
                return;
            }
        }
        
        auto dbClient = app().getDbClient();
        
        // Check if color is already taken
        *dbClient << "SELECT id FROM users WHERE user_color = $1 AND id != $2 LIMIT 1"
                  << newColor << userId
                  >> [dbClient, userId, newColor, callback](const Result& r) {
                      if (!r.empty()) {
                          callback(false, "This color is already taken", "");
                          return;
                      }
                      
                      // Update the color
                      *dbClient << "UPDATE users SET user_color = $1 WHERE id = $2 RETURNING user_color"
                               << newColor << userId
                               >> [callback, newColor](const Result& r2) {
                                   if (!r2.empty()) {
                                       callback(true, "", newColor);
                                   } else {
                                       callback(false, "Failed to update color", "");
                                   }
                               }
                               >> [callback](const DrogonDbException& e) {
                                   LOG_ERROR << "Failed to update color: " << e.base().what();
                                   callback(false, "Database error", "");
                               };
                  }
                  >> [callback](const DrogonDbException& e) {
                      LOG_ERROR << "Database error: " << e.base().what();
                      callback(false, "Database error", "");
                  };
    } catch (const std::exception& e) {
        LOG_ERROR << "Exception in updateUserColor: " << e.what();
        callback(false, "Internal server error", "");
    }
}

void AuthService::registerUser(const std::string& username, const std::string& password,
                              const std::string& publicKey, const std::string& fingerprint,
                              std::function<void(bool, const std::string&, int64_t)> callback) {
    try {
        LOG_DEBUG << "Starting user registration for: " << username;
        
        // Validate username
        if (username.length() < 3 || username.length() > 30) {
            callback(false, "Username must be between 3 and 30 characters", 0);
            return;
        }
        
        if (!std::regex_match(username, std::regex("^[a-zA-Z][a-zA-Z0-9_]*$"))) {
            callback(false, "Username must start with a letter and contain only letters, numbers, and underscores", 0);
            return;
        }
        
        // Validate password
        std::string error;
        if (!validatePassword(password, error)) {
            callback(false, error, 0);
            return;
        }
        
        LOG_DEBUG << "Validation passed, generating unique color";
        
        // Generate unique color first
        generateUniqueColor([this, username, password, publicKey, fingerprint, callback](const std::string& color) {
            try {
                LOG_DEBUG << "Got unique color: " << color << ", checking username availability";
                
                auto dbClient = app().getDbClient();
                if (!dbClient) {
                    LOG_ERROR << "Database client is null";
                    callback(false, "Database connection error", 0);
                    return;
                }
                
                // Check if username exists
                *dbClient << "SELECT id FROM users WHERE username = $1 LIMIT 1"
                          << username
                          >> [dbClient, username, password, publicKey, fingerprint, color, callback](const Result& r) {
                              try {
                                  if (!r.empty()) {
                                      LOG_WARN << "Username already exists: " << username;
                                      callback(false, "Username already exists", 0);
                                      return;
                                  }
                                  
                                  LOG_DEBUG << "Username available, checking fingerprint";
                                  
                                  // Check if fingerprint exists
                                  *dbClient << "SELECT id FROM pgp_keys WHERE fingerprint = $1 LIMIT 1"
                                           << fingerprint
                                           >> [dbClient, username, password, publicKey, fingerprint, color, callback](const Result& r2) {
                                               try {
                                                   if (!r2.empty()) {
                                                       LOG_WARN << "Fingerprint already exists";
                                                       callback(false, "This PGP key is already registered", 0);
                                                       return;
                                                   }
                                                   
                                                   LOG_DEBUG << "Fingerprint available, hashing password";
                                                   
                                                   // Hash password
                                                   std::string hash;
                                                   try {
                                                       hash = BCrypt::generateHash(password);
                                                   } catch (const std::exception& e) {
                                                       LOG_ERROR << "Failed to hash password: " << e.what();
                                                       callback(false, "Failed to process password", 0);
                                                       return;
                                                   }
                                                   
                                                   LOG_DEBUG << "Password hashed, inserting user";
                                                   
                                                   // Insert user first (without transaction for simplicity)
                                                   *dbClient << "INSERT INTO users (username, password_hash, is_admin, is_streamer, is_pgp_only, user_color) "
                                                            "VALUES ($1, $2, false, false, false, $3) RETURNING id"
                                                          << username << hash << color
                                                          >> [dbClient, publicKey, fingerprint, callback, username](const Result& r3) {
                                                              try {
                                                                  if (r3.empty()) {
                                                                      LOG_ERROR << "Failed to insert user";
                                                                      callback(false, "Failed to create user", 0);
                                                                      return;
                                                                  }
                                                                  
                                                                  int64_t userId = r3[0]["id"].as<int64_t>();
                                                                  LOG_INFO << "User created with ID: " << userId;
                                                                  
                                                                  // Insert PGP key
                                                                  *dbClient << "INSERT INTO pgp_keys (user_id, public_key, fingerprint) VALUES ($1, $2, $3)"
                                                                           << userId << publicKey << fingerprint
                                                                           >> [callback, userId, username](const Result&) {
                                                                               LOG_INFO << "User registration complete for: " << username << " (ID: " << userId << ")";
                                                                               callback(true, "", userId);
                                                                           }
                                                                           >> [dbClient, userId, callback](const DrogonDbException& e) {
                                                                               LOG_ERROR << "Failed to insert PGP key: " << e.base().what();
                                                                               // Try to clean up the user
                                                                               *dbClient << "DELETE FROM users WHERE id = $1" << userId >> [](const Result&) {} >> [](const DrogonDbException&) {};
                                                                               callback(false, "Failed to save PGP key", 0);
                                                                           };
                                                              } catch (const std::exception& e) {
                                                                  LOG_ERROR << "Exception processing user insert result: " << e.what();
                                                                  callback(false, "Registration failed", 0);
                                                              }
                                                          }
                                                          >> [callback](const DrogonDbException& e) {
                                                              LOG_ERROR << "Failed to insert user: " << e.base().what();
                                                              callback(false, "Registration failed", 0);
                                                          };
                                               } catch (const std::exception& e) {
                                                   LOG_ERROR << "Exception in fingerprint check callback: " << e.what();
                                                   callback(false, "Registration failed", 0);
                                               }
                                           }
                                           >> [callback](const DrogonDbException& e) {
                                               LOG_ERROR << "Database error checking fingerprint: " << e.base().what();
                                               callback(false, "Database error", 0);
                                           };
                              } catch (const std::exception& e) {
                                  LOG_ERROR << "Exception in username check callback: " << e.what();
                                  callback(false, "Registration failed", 0);
                              }
                          }
                          >> [callback](const DrogonDbException& e) {
                              LOG_ERROR << "Database error checking username: " << e.base().what();
                              callback(false, "Database error", 0);
                          };
            } catch (const std::exception& e) {
                LOG_ERROR << "Exception in color generation callback: " << e.what();
                callback(false, "Registration failed", 0);
            }
        });
    } catch (const std::exception& e) {
        LOG_ERROR << "Exception in registerUser: " << e.what();
        callback(false, "Registration failed", 0);
    }
}

void AuthService::loginUser(const std::string& username, const std::string& password,
                           std::function<void(bool, const std::string&, const UserInfo&)> callback) {
    try {
        auto dbClient = app().getDbClient();
        if (!dbClient) {
            LOG_ERROR << "Database client is null";
            callback(false, "", UserInfo{});
            return;
        }
        
        *dbClient << "SELECT id, username, password_hash, is_admin, is_moderator, is_streamer, is_restreamer, is_bot, is_texter, is_pgp_only, is_disabled, bio, avatar_url, banner_url, banner_position, banner_zoom, banner_position_x, graffiti_url, pgp_only_enabled_at, user_color "
                     "FROM users WHERE username = $1 LIMIT 1"
                  << username
                  >> [password, callback, this](const Result& r) {
                      try {
                          if (r.empty()) {
                              callback(false, "", UserInfo{});
                              return;
                          }

                          // Check if account is disabled
                          bool isDisabled = r[0]["is_disabled"].isNull() ? false : r[0]["is_disabled"].as<bool>();
                          if (isDisabled) {
                              callback(false, "Account disabled", UserInfo{});
                              return;
                          }

                          // Check if PGP-only is enabled BEFORE password validation
                          bool isPgpOnly = r[0]["is_pgp_only"].isNull() ? false : r[0]["is_pgp_only"].as<bool>();

                          if (isPgpOnly) {
                              // Return a specific error for PGP-only accounts
                              callback(false, "PGP-only login enabled for this account", UserInfo{});
                              return;
                          }

                          std::string hash = r[0]["password_hash"].as<std::string>();

                          bool valid = false;
                          try {
                              valid = BCrypt::validatePassword(password, hash);
                          } catch (const std::exception& e) {
                              LOG_ERROR << "Failed to validate password: " << e.what();
                              callback(false, "", UserInfo{});
                              return;
                          }

                          if (!valid) {
                              callback(false, "", UserInfo{});
                              return;
                          }

                          UserInfo user;
                          user.id = r[0]["id"].as<int64_t>();
                          user.username = r[0]["username"].as<std::string>();
                          user.isAdmin = r[0]["is_admin"].isNull() ? false : r[0]["is_admin"].as<bool>();
                          user.isModerator = r[0]["is_moderator"].isNull() ? false : r[0]["is_moderator"].as<bool>();
                          user.isStreamer = r[0]["is_streamer"].isNull() ? false : r[0]["is_streamer"].as<bool>();
                          user.isRestreamer = r[0]["is_restreamer"].isNull() ? false : r[0]["is_restreamer"].as<bool>();
                          user.isBot = r[0]["is_bot"].isNull() ? false : r[0]["is_bot"].as<bool>();
                          user.isTexter = r[0]["is_texter"].isNull() ? false : r[0]["is_texter"].as<bool>();
                          user.isPgpOnly = isPgpOnly;
                          user.bio = r[0]["bio"].isNull() ? "" : r[0]["bio"].as<std::string>();
                          user.avatarUrl = r[0]["avatar_url"].isNull() ? "" : r[0]["avatar_url"].as<std::string>();
                          user.bannerUrl = r[0]["banner_url"].isNull() ? "" : r[0]["banner_url"].as<std::string>();
                          user.bannerPosition = r[0]["banner_position"].isNull() ? 50 : r[0]["banner_position"].as<int>();
                          user.bannerZoom = r[0]["banner_zoom"].isNull() ? 100 : r[0]["banner_zoom"].as<int>();
                          user.bannerPositionX = r[0]["banner_position_x"].isNull() ? 50 : r[0]["banner_position_x"].as<int>();
                          user.graffitiUrl = r[0]["graffiti_url"].isNull() ? "" : r[0]["graffiti_url"].as<std::string>();
                          user.pgpOnlyEnabledAt = r[0]["pgp_only_enabled_at"].isNull() ? "" : r[0]["pgp_only_enabled_at"].as<std::string>();
                          user.colorCode = r[0]["user_color"].isNull() ? "#561D5E" : r[0]["user_color"].as<std::string>();

                          std::string token = generateToken(user);
                          callback(true, token, user);
                      } catch (const std::exception& e) {
                          LOG_ERROR << "Exception in login callback: " << e.what();
                          callback(false, "", UserInfo{});
                      }
                  }
                  >> [callback](const DrogonDbException& e) {
                      LOG_ERROR << "Database error: " << e.base().what();
                      callback(false, "", UserInfo{});
                  };
    } catch (const std::exception& e) {
        LOG_ERROR << "Exception in loginUser: " << e.what();
        callback(false, "", UserInfo{});
    }
}

void AuthService::initiatePgpLogin(const std::string& username,
                                  std::function<void(bool, const std::string&, const std::string&)> callback) {
    try {
        auto dbClient = app().getDbClient();
        if (!dbClient) {
            LOG_ERROR << "Database client is null";
            callback(false, "", "");
            return;
        }
        
        // Generate random challenge
        auto bytes = drogon::utils::genRandomString(32);
        std::string challenge = drogon::utils::base64Encode(
            reinterpret_cast<const unsigned char*>(bytes.data()), bytes.length()
        );
        
        // Store challenge in Redis with 5 minute TTL
        RedisHelper::storeKeyAsync("pgp_challenge:" + username, challenge, 300,
            [dbClient, username, challenge, callback](bool stored) {
                if (!stored) {
                    callback(false, "", "");
                    return;
                }
                
                // Get user's latest public key
                *dbClient << "SELECT pk.public_key FROM pgp_keys pk "
                            "JOIN users u ON pk.user_id = u.id "
                            "WHERE u.username = $1 "
                            "ORDER BY pk.created_at DESC LIMIT 1"
                          << username
                          >> [callback, challenge](const Result& r) {
                              if (r.empty()) {
                                  callback(false, "", "");
                                  return;
                              }
                              
                              std::string publicKey = r[0]["public_key"].as<std::string>();
                              callback(true, challenge, publicKey);
                          }
                          >> [callback](const DrogonDbException& e) {
                              LOG_ERROR << "Database error: " << e.base().what();
                              callback(false, "", "");
                          };
            }
        );
    } catch (const std::exception& e) {
        LOG_ERROR << "Exception in initiatePgpLogin: " << e.what();
        callback(false, "", "");
    }
}

void AuthService::verifyPgpLogin(const std::string& username, const std::string& signature, 
                                const std::string& challenge,
                                std::function<void(bool, const std::string&, const UserInfo&)> callback) {
    try {
        // Get stored challenge from Redis
        RedisHelper::getKeyAsync("pgp_challenge:" + username,
            [username, signature, challenge, callback, this](const std::string& storedChallenge) {
                try {
                    if (storedChallenge.empty() || storedChallenge != challenge) {
                        LOG_WARN << "Challenge mismatch for user: " << username;
                        callback(false, "", UserInfo{});
                        return;
                    }
                    
                    // Delete challenge after use
                    RedisHelper::deleteKeyAsync("pgp_challenge:" + username, [](bool) {});
                    
                    // Get user's public key and verify signature
                    auto dbClient = app().getDbClient();
                    if (!dbClient) {
                        LOG_ERROR << "Database client is null";
                        callback(false, "", UserInfo{});
                        return;
                    }
                    
                    *dbClient << "SELECT pk.public_key, u.id, u.username, u.is_admin, u.is_moderator, u.is_streamer, u.is_restreamer, u.is_bot, u.is_texter, "
                                "u.is_pgp_only, u.is_disabled, u.bio, u.avatar_url, u.banner_url, u.banner_position, u.banner_zoom, u.banner_position_x, u.graffiti_url, u.pgp_only_enabled_at, u.user_color "
                                "FROM pgp_keys pk JOIN users u ON pk.user_id = u.id "
                                "WHERE u.username = $1 ORDER BY pk.created_at DESC LIMIT 1"
                              << username
                              >> [callback, signature, challenge, this](const Result& r) {
                                  try {
                                      if (r.empty()) {
                                          LOG_WARN << "No PGP key found for user";
                                          callback(false, "", UserInfo{});
                                          return;
                                      }

                                      // Check if account is disabled
                                      bool isDisabled = r[0]["is_disabled"].isNull() ? false : r[0]["is_disabled"].as<bool>();
                                      if (isDisabled) {
                                          callback(false, "Account disabled", UserInfo{});
                                          return;
                                      }

                                      std::string publicKey = r[0]["public_key"].as<std::string>();

                                      // CRITICAL: Server-side signature verification
                                      bool signatureValid = verifyPgpSignature(challenge, signature, publicKey);

                                      if (!signatureValid) {
                                          LOG_WARN << "Invalid PGP signature for user";
                                          callback(false, "Invalid signature", UserInfo{});
                                          return;
                                      }

                                      LOG_INFO << "PGP signature verified successfully for user";

                                      UserInfo user;
                                      user.id = r[0]["id"].as<int64_t>();
                                      user.username = r[0]["username"].as<std::string>();
                                      user.isAdmin = r[0]["is_admin"].isNull() ? false : r[0]["is_admin"].as<bool>();
                                      user.isModerator = r[0]["is_moderator"].isNull() ? false : r[0]["is_moderator"].as<bool>();
                                      user.isStreamer = r[0]["is_streamer"].isNull() ? false : r[0]["is_streamer"].as<bool>();
                                      user.isRestreamer = r[0]["is_restreamer"].isNull() ? false : r[0]["is_restreamer"].as<bool>();
                                      user.isBot = r[0]["is_bot"].isNull() ? false : r[0]["is_bot"].as<bool>();
                                      user.isTexter = r[0]["is_texter"].isNull() ? false : r[0]["is_texter"].as<bool>();
                                      user.isPgpOnly = r[0]["is_pgp_only"].isNull() ? false : r[0]["is_pgp_only"].as<bool>();
                                      user.bio = r[0]["bio"].isNull() ? "" : r[0]["bio"].as<std::string>();
                                      user.avatarUrl = r[0]["avatar_url"].isNull() ? "" : r[0]["avatar_url"].as<std::string>();
                                      user.bannerUrl = r[0]["banner_url"].isNull() ? "" : r[0]["banner_url"].as<std::string>();
                                      user.bannerPosition = r[0]["banner_position"].isNull() ? 50 : r[0]["banner_position"].as<int>();
                                      user.bannerZoom = r[0]["banner_zoom"].isNull() ? 100 : r[0]["banner_zoom"].as<int>();
                                      user.bannerPositionX = r[0]["banner_position_x"].isNull() ? 50 : r[0]["banner_position_x"].as<int>();
                                      user.graffitiUrl = r[0]["graffiti_url"].isNull() ? "" : r[0]["graffiti_url"].as<std::string>();
                                      user.pgpOnlyEnabledAt = r[0]["pgp_only_enabled_at"].isNull() ? "" : r[0]["pgp_only_enabled_at"].as<std::string>();
                                      user.colorCode = r[0]["user_color"].isNull() ? "#561D5E" : r[0]["user_color"].as<std::string>();

                                      std::string token = generateToken(user);
                                      callback(true, token, user);
                                  } catch (const std::exception& e) {
                                      LOG_ERROR << "Exception processing user data: " << e.what();
                                      callback(false, "", UserInfo{});
                                  }
                              }
                              >> [callback](const DrogonDbException& e) {
                                  LOG_ERROR << "Database error: " << e.base().what();
                                  callback(false, "", UserInfo{});
                              };
                } catch (const std::exception& e) {
                    LOG_ERROR << "Exception in Redis callback: " << e.what();
                    callback(false, "", UserInfo{});
                }
            }
        );
    } catch (const std::exception& e) {
        LOG_ERROR << "Exception in verifyPgpLogin: " << e.what();
        callback(false, "", UserInfo{});
    }
}

// SECURITY FIX #5: Validate JWT secret has minimum length and entropy
void AuthService::validateAndLoadJwtSecret() {
    if (!jwtSecret_.empty()) {
        return;  // Already loaded and validated
    }

    const char* envSecret = std::getenv("JWT_SECRET");
    if (!envSecret || strlen(envSecret) == 0) {
        throw std::runtime_error("JWT_SECRET environment variable is not set");
    }

    size_t secretLen = strlen(envSecret);

    // Require at least 32 characters (256 bits) for HS256
    if (secretLen < 32) {
        throw std::runtime_error("JWT_SECRET must be at least 32 characters (256 bits) for security");
    }

    // Basic entropy check - ensure not all same character
    bool hasVariety = false;
    for (size_t i = 1; i < secretLen && !hasVariety; ++i) {
        if (envSecret[i] != envSecret[0]) {
            hasVariety = true;
        }
    }
    if (!hasVariety) {
        throw std::runtime_error("JWT_SECRET has insufficient entropy - all characters are the same");
    }

    // Check for common weak secrets
    std::string secretLower = envSecret;
    std::transform(secretLower.begin(), secretLower.end(), secretLower.begin(), ::tolower);
    if (secretLower.find("secret") != std::string::npos ||
        secretLower.find("password") != std::string::npos ||
        secretLower.find("123456") != std::string::npos) {
        LOG_WARN << "JWT_SECRET appears to contain common weak patterns - consider using a stronger secret";
    }

    jwtSecret_ = std::string(envSecret);
    LOG_INFO << "JWT secret loaded and validated (" << secretLen << " characters)";
}

std::string AuthService::generateToken(const UserInfo& user) {
    try {
        validateAndLoadJwtSecret();

        // SECURITY FIX: Reduced JWT expiry from 24h to 1h to limit token exposure window
        auto token = jwt::create()
            .set_issuer("streaming-app")
            .set_type("JWT")
            .set_issued_at(std::chrono::system_clock::now())
            .set_expires_at(std::chrono::system_clock::now() + std::chrono::hours(1))
            .set_payload_claim("user_id", jwt::claim(std::to_string(user.id)))
            .set_payload_claim("username", jwt::claim(user.username))
            .set_payload_claim("is_admin", jwt::claim(std::to_string(user.isAdmin)))
            .set_payload_claim("is_moderator", jwt::claim(std::to_string(user.isModerator)))
            .set_payload_claim("is_streamer", jwt::claim(std::to_string(user.isStreamer)))
            .set_payload_claim("is_restreamer", jwt::claim(std::to_string(user.isRestreamer)))
            .set_payload_claim("is_disabled", jwt::claim(std::to_string(user.isDisabled)))  // SECURITY FIX #26
            .set_payload_claim("token_version", jwt::claim(std::to_string(user.tokenVersion)))  // SECURITY FIX #10
            .set_payload_claim("color_code", jwt::claim(
                user.colorCode.empty() ? "#561D5E" : user.colorCode
            ))  // Ensure color is never empty
            .set_payload_claim("avatar_url", jwt::claim(user.avatarUrl))
            .sign(jwt::algorithm::hs256{jwtSecret_});
        
        return token;
    } catch (const std::exception& e) {
        LOG_ERROR << "Failed to generate token: " << e.what();
        return "";
    }
}

bool AuthService::validateToken(const std::string& token, UserInfo& userInfo) {
    try {
        validateAndLoadJwtSecret();

        auto decoded = jwt::decode(token);
        
        auto verifier = jwt::verify()
            .allow_algorithm(jwt::algorithm::hs256{jwtSecret_})
            .with_issuer("streaming-app");
        
        verifier.verify(decoded);
        
        userInfo.id = std::stoll(decoded.get_payload_claim("user_id").as_string());
        userInfo.username = decoded.get_payload_claim("username").as_string();
        userInfo.isAdmin = decoded.get_payload_claim("is_admin").as_string() == "1";
        userInfo.isModerator = decoded.has_payload_claim("is_moderator") ?
            decoded.get_payload_claim("is_moderator").as_string() == "1" : false;
        userInfo.isStreamer = decoded.has_payload_claim("is_streamer") ?
            decoded.get_payload_claim("is_streamer").as_string() == "1" : false;
        userInfo.isRestreamer = decoded.has_payload_claim("is_restreamer") ?
            decoded.get_payload_claim("is_restreamer").as_string() == "1" : false;

        // SECURITY FIX #26: Extract disabled status
        userInfo.isDisabled = decoded.has_payload_claim("is_disabled") ?
            decoded.get_payload_claim("is_disabled").as_string() == "1" : false;

        // SECURITY FIX #10: Extract token version for revocation check
        userInfo.tokenVersion = decoded.has_payload_claim("token_version") ?
            std::stoi(decoded.get_payload_claim("token_version").as_string()) : 1;

        // Get color from token if available, otherwise will need to fetch from DB
        if (decoded.has_payload_claim("color_code")) {
            userInfo.colorCode = decoded.get_payload_claim("color_code").as_string();
        } else {
            // For older tokens without color, default value
            userInfo.colorCode = "#561D5E";
        }

        // SECURITY FIX #26: Reject tokens from disabled accounts
        if (userInfo.isDisabled) {
            LOG_DEBUG << "Token rejected - user account is disabled: " << userInfo.username;
            return false;
        }

        return true;
    } catch (const std::exception& e) {
        LOG_DEBUG << "Token validation failed: " << e.what();
        return false;
    }
}

// Chat service compatibility method
std::optional<UserClaims> AuthService::verifyToken(const std::string& token) {
    UserInfo userInfo;
    if (validateToken(token, userInfo)) {
        UserClaims claims;
        claims.userId = std::to_string(userInfo.id);
        claims.username = userInfo.username;
        claims.userColor = userInfo.colorCode;
        claims.isAdmin = userInfo.isAdmin;
        claims.isModerator = userInfo.isModerator;
        claims.isStreamer = userInfo.isStreamer;
        claims.isRestreamer = userInfo.isRestreamer;
        return claims;
    }
    return std::nullopt;
}

void AuthService::updatePassword(int64_t userId, const std::string& oldPassword, 
                                const std::string& newPassword,
                                std::function<void(bool, const std::string&)> callback) {
    try {
        // Validate new password
        std::string error;
        if (!validatePassword(newPassword, error)) {
            callback(false, error);
            return;
        }
        
        auto dbClient = app().getDbClient();
        if (!dbClient) {
            LOG_ERROR << "Database client is null";
            callback(false, "Database connection error");
            return;
        }
        
        // Verify old password
        *dbClient << "SELECT password_hash FROM users WHERE id = $1 LIMIT 1"
                  << userId
                  >> [oldPassword, newPassword, userId, dbClient, callback](const Result& r) {
                      try {
                          if (r.empty()) {
                              callback(false, "User not found");
                              return;
                          }
                          
                          std::string hash = r[0]["password_hash"].as<std::string>();
                          
                          bool valid = false;
                          try {
                              valid = BCrypt::validatePassword(oldPassword, hash);
                          } catch (const std::exception& e) {
                              LOG_ERROR << "Failed to validate password: " << e.what();
                              callback(false, "Password validation error");
                              return;
                          }
                          
                          if (!valid) {
                              callback(false, "Incorrect password");
                              return;
                          }
                          
                          // Update password
                          std::string newHash;
                          try {
                              newHash = BCrypt::generateHash(newPassword);
                          } catch (const std::exception& e) {
                              LOG_ERROR << "Failed to hash new password: " << e.what();
                              callback(false, "Failed to process new password");
                              return;
                          }
                          
                          // SECURITY FIX #10: Increment token_version to invalidate all existing tokens
                          *dbClient << "UPDATE users SET password_hash = $1, token_version = COALESCE(token_version, 0) + 1 WHERE id = $2"
                                   << newHash << userId
                                   >> [callback, userId](const Result&) {
                                       LOG_INFO << "Password updated and token_version incremented for user " << userId;
                                       callback(true, "");
                                   }
                                   >> [callback](const DrogonDbException& e) {
                                       LOG_ERROR << "Failed to update password: " << e.base().what();
                                       callback(false, "Failed to update password");
                                   };
                      } catch (const std::exception& e) {
                          LOG_ERROR << "Exception in password update callback: " << e.what();
                          callback(false, "Failed to update password");
                      }
                  }
                  >> [callback](const DrogonDbException& e) {
                      LOG_ERROR << "Database error: " << e.base().what();
                      callback(false, "Database error");
                  };
    } catch (const std::exception& e) {
        LOG_ERROR << "Exception in updatePassword: " << e.what();
        callback(false, "Failed to update password");
    }
}

void AuthService::fetchUserInfo(int64_t userId, std::function<void(bool, const UserInfo&)> callback) {
    try {
        auto dbClient = app().getDbClient();
        if (!dbClient) {
            LOG_ERROR << "Database client is null";
            callback(false, UserInfo{});
            return;
        }
        
        *dbClient << "SELECT id, username, is_admin, is_moderator, is_streamer, is_restreamer, is_bot, is_texter, is_pgp_only, bio, avatar_url, banner_url, banner_position, banner_zoom, banner_position_x, graffiti_url, pgp_only_enabled_at, user_color "
                     "FROM users WHERE id = $1 LIMIT 1"
                  << userId
                  >> [callback](const Result& r) {
                      try {
                          if (r.empty()) {
                              callback(false, UserInfo{});
                              return;
                          }

                          UserInfo user;
                          user.id = r[0]["id"].as<int64_t>();
                          user.username = r[0]["username"].as<std::string>();
                          user.isAdmin = r[0]["is_admin"].isNull() ? false : r[0]["is_admin"].as<bool>();
                          user.isModerator = r[0]["is_moderator"].isNull() ? false : r[0]["is_moderator"].as<bool>();
                          user.isStreamer = r[0]["is_streamer"].isNull() ? false : r[0]["is_streamer"].as<bool>();
                          user.isRestreamer = r[0]["is_restreamer"].isNull() ? false : r[0]["is_restreamer"].as<bool>();
                          user.isBot = r[0]["is_bot"].isNull() ? false : r[0]["is_bot"].as<bool>();
                          user.isTexter = r[0]["is_texter"].isNull() ? false : r[0]["is_texter"].as<bool>();
                          user.isPgpOnly = r[0]["is_pgp_only"].isNull() ? false : r[0]["is_pgp_only"].as<bool>();
                          user.bio = r[0]["bio"].isNull() ? "" : r[0]["bio"].as<std::string>();
                          user.avatarUrl = r[0]["avatar_url"].isNull() ? "" : r[0]["avatar_url"].as<std::string>();
                          user.bannerUrl = r[0]["banner_url"].isNull() ? "" : r[0]["banner_url"].as<std::string>();
                          user.bannerPosition = r[0]["banner_position"].isNull() ? 50 : r[0]["banner_position"].as<int>();
                          user.bannerZoom = r[0]["banner_zoom"].isNull() ? 100 : r[0]["banner_zoom"].as<int>();
                          user.bannerPositionX = r[0]["banner_position_x"].isNull() ? 50 : r[0]["banner_position_x"].as<int>();
                          user.graffitiUrl = r[0]["graffiti_url"].isNull() ? "" : r[0]["graffiti_url"].as<std::string>();
                          user.pgpOnlyEnabledAt = r[0]["pgp_only_enabled_at"].isNull() ? "" : r[0]["pgp_only_enabled_at"].as<std::string>();
                          user.colorCode = r[0]["user_color"].isNull() ? "#561D5E" : r[0]["user_color"].as<std::string>();

                          callback(true, user);
                      } catch (const std::exception& e) {
                          LOG_ERROR << "Exception processing user data: " << e.what();
                          callback(false, UserInfo{});
                      }
                  }
                  >> [callback](const DrogonDbException& e) {
                      LOG_ERROR << "Database error: " << e.base().what();
                      callback(false, UserInfo{});
                  };
    } catch (const std::exception& e) {
        LOG_ERROR << "Exception in fetchUserInfo: " << e.what();
        callback(false, UserInfo{});
    }
}