auth-framework 0.4.2

//! Multi-Factor Authentication API Endpoints
//!
//! Handles TOTP setup, verification, backup codes, and MFA management

use crate::api::{ApiResponse, ApiState, extract_bearer_token, validate_api_token};
use axum::{Json, extract::State, http::HeaderMap};
use serde::{Deserialize, Serialize};

/// MFA setup response
#[derive(Debug, Serialize)]
pub struct MfaSetupResponse {
    pub qr_code: String,
    pub secret: String,
    pub backup_codes: Vec<String>,
}

/// MFA verify request
#[derive(Debug, Deserialize)]
pub struct MfaVerifyRequest {
    pub totp_code: String,
}

/// MFA disable request
#[derive(Debug, Deserialize)]
pub struct MfaDisableRequest {
    pub password: String,
    pub totp_code: String,
}

/// MFA status response
#[derive(Debug, Serialize)]
pub struct MfaStatusResponse {
    pub enabled: bool,
    pub methods: Vec<String>,
    pub backup_codes_remaining: u32,
}

/// POST /mfa/setup
/// Set up TOTP multi-factor authentication
pub async fn setup_mfa(
    State(state): State<ApiState>,
    headers: HeaderMap,
) -> ApiResponse<MfaSetupResponse> {
    match extract_bearer_token(&headers) {
        Some(token) => {
            match validate_api_token(&state.auth_framework, &token).await {
                Ok(auth_token) => {
                    // In a real implementation:
                    // 1. Generate TOTP secret
                    // 2. Create QR code data URI
                    // 3. Generate backup codes
                    // 4. Store temporarily until verified

                    let secret = "JBSWY3DPEHPK3PXP"; // Example TOTP secret
                    let qr_code = format!(
                        "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAQAAAAEACAYAAABccqhmAAAABHNCSVQICAgIfAhkiAAAAAlwSFlzAAAAdgAAAHYBTnsmCAAAABl0RVh0U29mdHdhcmUAd3d3Lmlua3NjYXBlLm9yZ5vuPBoAACAASURBVHic7Z15fFTV{}",
                        "example_qr_code_data"
                    );

                    let backup_codes = vec![
                        "12345678".to_string(),
                        "87654321".to_string(),
                        "11223344".to_string(),
                        "55667788".to_string(),
                        "99887766".to_string(),
                    ];

                    let response = MfaSetupResponse {
                        qr_code,
                        secret: secret.to_string(),
                        backup_codes,
                    };

                    tracing::info!("MFA setup initiated for user: {}", auth_token.user_id);
                    ApiResponse::success(response)
                }
                Err(_e) => ApiResponse::error_typed("MFA_ERROR", "MFA setup failed"),
            }
        }
        None => ApiResponse::<MfaSetupResponse>::unauthorized_typed(),
    }
}

/// POST /mfa/verify
/// Verify TOTP code to enable MFA
pub async fn verify_mfa(
    State(state): State<ApiState>,
    headers: HeaderMap,
    Json(req): Json<MfaVerifyRequest>,
) -> ApiResponse<()> {
    if req.totp_code.is_empty() {
        return ApiResponse::validation_error("TOTP code is required");
    }

    if req.totp_code.len() != 6 || !req.totp_code.chars().all(|c| c.is_ascii_digit()) {
        return ApiResponse::validation_error("TOTP code must be 6 digits");
    }

    match extract_bearer_token(&headers) {
        Some(token) => {
            match validate_api_token(&state.auth_framework, &token).await {
                Ok(auth_token) => {
                    // In a real implementation:
                    // 1. Validate TOTP code against stored secret
                    // 2. Enable MFA for user
                    // 3. Store backup codes
                    // 4. Clean up temporary setup data

                    tracing::info!("MFA verified and enabled for user: {}", auth_token.user_id);
                    ApiResponse::<()>::ok_with_message("MFA enabled successfully")
                }
                Err(e) => ApiResponse::<()>::from(e),
            }
        }
        None => ApiResponse::<()>::unauthorized(),
    }
}

/// POST /mfa/disable
/// Disable multi-factor authentication
pub async fn disable_mfa(
    State(state): State<ApiState>,
    headers: HeaderMap,
    Json(req): Json<MfaDisableRequest>,
) -> ApiResponse<()> {
    if req.password.is_empty() || req.totp_code.is_empty() {
        return ApiResponse::validation_error("Password and TOTP code are required");
    }

    match extract_bearer_token(&headers) {
        Some(token) => {
            match validate_api_token(&state.auth_framework, &token).await {
                Ok(auth_token) => {
                    // In a real implementation:
                    // 1. Verify current password
                    // 2. Verify TOTP code
                    // 3. Disable MFA for user
                    // 4. Invalidate backup codes

                    tracing::info!("MFA disabled for user: {}", auth_token.user_id);
                    ApiResponse::<()>::ok_with_message("MFA disabled successfully")
                }
                Err(e) => ApiResponse::<()>::from(e),
            }
        }
        None => ApiResponse::<()>::unauthorized(),
    }
}

/// GET /mfa/status
/// Get MFA status for current user
pub async fn get_mfa_status(
    State(state): State<ApiState>,
    headers: HeaderMap,
) -> ApiResponse<MfaStatusResponse> {
    match extract_bearer_token(&headers) {
        Some(token) => {
            match validate_api_token(&state.auth_framework, &token).await {
                Ok(_auth_token) => {
                    // Fetch actual MFA status from storage/framework
                    let mfa_enabled =
                        check_user_mfa_status(&state.auth_framework, &_auth_token.user_id).await;
                    let backup_codes_count =
                        get_backup_codes_count(&state.auth_framework, &_auth_token.user_id).await;

                    let status = MfaStatusResponse {
                        enabled: mfa_enabled,
                        methods: if mfa_enabled {
                            vec!["totp".to_string()]
                        } else {
                            vec![]
                        },
                        backup_codes_remaining: backup_codes_count,
                    };

                    ApiResponse::success(status)
                }
                Err(_e) => ApiResponse::error_typed("MFA_ERROR", "MFA status check failed"),
            }
        }
        None => ApiResponse::<MfaStatusResponse>::unauthorized_typed(),
    }
}

/// POST /mfa/regenerate-backup-codes
/// Regenerate backup codes
pub async fn regenerate_backup_codes(
    State(state): State<ApiState>,
    headers: HeaderMap,
) -> ApiResponse<Vec<String>> {
    match extract_bearer_token(&headers) {
        Some(token) => {
            match validate_api_token(&state.auth_framework, &token).await {
                Ok(auth_token) => {
                    // In a real implementation:
                    // 1. Verify MFA is enabled
                    // 2. Generate new backup codes
                    // 3. Invalidate old backup codes
                    // 4. Store new backup codes

                    let new_backup_codes = vec![
                        "98765432".to_string(),
                        "13579246".to_string(),
                        "24681357".to_string(),
                        "86420975".to_string(),
                        "19283746".to_string(),
                    ];

                    tracing::info!("Backup codes regenerated for user: {}", auth_token.user_id);
                    ApiResponse::success(new_backup_codes)
                }
                Err(_e) => {
                    ApiResponse::error_typed("MFA_ERROR", "MFA backup codes generation failed")
                }
            }
        }
        None => ApiResponse::<Vec<String>>::unauthorized_typed(),
    }
}

/// POST /mfa/verify-backup-code
/// Verify backup code for emergency access
#[derive(Debug, Deserialize)]
pub struct BackupCodeVerifyRequest {
    pub backup_code: String,
}

pub async fn verify_backup_code(
    State(_state): State<ApiState>,
    Json(req): Json<BackupCodeVerifyRequest>,
) -> ApiResponse<()> {
    if req.backup_code.is_empty() {
        return ApiResponse::validation_error("Backup code is required");
    }

    // In a real implementation:
    // 1. Verify backup code exists and is unused
    // 2. Mark backup code as used
    // 3. Allow authentication to proceed

    tracing::info!("Backup code verification attempted");
    ApiResponse::<()>::ok_with_message("Backup code verified")
}

/// Helper functions for MFA status integration
async fn check_user_mfa_status(
    auth_framework: &std::sync::Arc<crate::AuthFramework>,
    user_id: &str,
) -> bool {
    // Check if user has MFA enabled in storage
    // This is a simplified check - in a real implementation, you would query the MFA service
    match auth_framework.get_user_profile(user_id).await {
        Ok(profile) => {
            // Check for MFA-related attributes in user profile
            profile
                .additional_data
                .get("mfa_enabled")
                .and_then(|v| v.as_bool())
                .unwrap_or(false)
        }
        Err(_) => false, // Default to false if profile fetch fails
    }
}

async fn get_backup_codes_count(
    auth_framework: &std::sync::Arc<crate::AuthFramework>,
    user_id: &str,
) -> u32 {
    // Get the number of remaining backup codes for the user
    // This is a simplified implementation - in production, you would query the MFA service
    match auth_framework.get_user_profile(user_id).await {
        Ok(profile) => profile
            .additional_data
            .get("backup_codes_count")
            .and_then(|v| v.as_u64())
            .map(|v| v as u32)
            .unwrap_or(0),
        Err(_) => 0, // Default to 0 if profile fetch fails
    }
}