# Rules Engine

## Goals:
* Support multiple types of rules
* Each rule needs to operate by itself
* Rules can also link together
* Rules should be linked to roles

## A Real Workflow:

### Holder connects to health_issuer

{
    name: "connect-holder-health-issuer",
    role: ["holder"], // Do we need this role or is it mapped in privileges? Array
    initial: "true",
    type: "action",
    data: {
        protocol: "https://didcomm.org/connections/1.0/",
        startmessage: "invitation"
    },
    next: {
        success: "validate-identity-information",
        error: "some-kind-of-error-handler..."
    }
}

### health_issuer requests id proof from holder

{
    name: "validate-identity-information",
    role: "issuer",
    initial: "true",
    type: "action",
    data: {
        protocol: "https://didcomm.org/present-proof/1.0/",
        startmessage: "request-presentation",
        presentation_definition: "http://localhost:3100/api/presentation-exchange-for-identity-proof"
    },
    next: "decision-country-of-origin"
}

### health_issuer make descision based on an input

{
    name: "decision-country-of-origin",
    role: ["travel-issuer"],
    type: "decision",
    data: {
        input_name: "country_of_origin",
        options: [
            {
                values: ["US","Canada"],
                next: "reject-country"
            },
            {
                values: ["Germany","Belgium"],
                next: "select-health-credentials"
            }
        ]     
    },
    next: {
        success: "select-health-credentials",
        error: "some-kind-of-error-handler..."
    }
}

### health_issuer issues health credentials

{
    name: "select-health-credentials",
    role: "issuer",
    type: "decision",
    data: {
        input_name: "requested_health_credential",
        options: [
            {
                value: "lab_result",
                next: "issue-lab-result"
            },
            {
                value: "exemption",
                next: "issue-exemption"
            },
            {
                value: "vaccination",
                next: "issue-vaccination"
            }
            
        ]       
    }
}

### health_issuer issues lab result

{
    name: "issue-lab-result",
    role: "issuer",
    type: "action",
    data: {
        schema: "RuuJwd3JMffNwZ43DcJKN1:2:Lab_Result:1.4",
        protocol: "https://didcomm.org/issue-credential/1.0/",
        startmessage: "offer-credential",
        presentation_definition: "http://localhost:3100/api/presentation-exchange-for-identity-proof",  
    },
    next: "request-health-proof"
}

### Holder responds with id presentation to health_issuer

{
    name: "present-identity-information",
    role: "holder",
    type: "action",
    data: {
        //protocol: "https://didcomm.org/issue-credential/1.0/",
        //startmessage: "offer-credential",
        schema: "RuuJwd3JMffNwZ43DcJKN1:2:Trusted_Traveler:1.4",
        presentation_definition: "http://localhost:3100/api/presentation-exchange-for-identity-proof"
    },
    next: "request-health-proof"
}

### health_issuer requests health proof from holder

{
    name: "request-health-proof",
    role: "holder",
    initial: "true",
    type: "action",
    data: {
        //protocol: "https://didcomm.org/issue-credential/1.0/",
        //startmessage: "offer-credential",
        schema: "RuuJwd3JMffNwZ43DcJKN1:2:Trusted_Traveler:1.4",
        presentation_definition: "http://localhost:3100/api/presentation-exchange-for-identity-proof",
    },
    next: "present-health-proof"
}

### Holder responds with health presentation to health issuer + additional data

{
    name: "present-health-proof",
    role: "holder",
    type: "action",
    data: {
        //protocol: "https://didcomm.org/issue-credential/1.0/",
        //startmessage: "offer-credential",
        schema: "RuuJwd3JMffNwZ43DcJKN1:2:Trusted_Traveler:1.4",
        presentation_definition: "http://localhost:3100/api/presentation-exchange-for-identity-proof",
    },
    next: "decision-country-of-origin"
}

### Helath issuer handle country rejection

{
    name: "reject-country",
    role: "holder",
    type: "action",
    data: {
        //protocol: "https://didcomm.org/issue-credential/1.0/",
        //startmessage: "offer-credential",
        schema: "RuuJwd3JMffNwZ43DcJKN1:2:Trusted_Traveler:1.4",
        presentation_definition: "http://localhost:3100/api/presentation-exchange"
    },
    next: "what_is_next?"
}

### health_issuer verifies health proof presentation

{
    name: "verify-health-credential",
    role: "traveler-issuer",
    type: "action",
    data: {
        protocol: "https://didcomm.org/present-proof/1.0/",
        startmessage: "request-presentation",
        presentation_definition: "http://localhost:3100/api/presentation-exchange"
    },
    next: {
        success: "validate-health-credential",
        error: "some-kind-of-error-handler..."
    }
}

### health_issuer validates health credential data

{
    name: "validate-health-credential",
    role: "traveler-issuer",
    type: "action",
    data: {
        presentation_definition: "http://localhost:3100/api/presentation-exchange"
    },
    next: {
        success: "issue-trusted-traveler-credential",
        error: "some-kind-of-error-handler..."
    }
}

### health_issuer issues trusted traveler

{
    name: "issue-trusted-traveler",
    role: "traveler-issuer",
    initial: "true",
    type: "action",
    data: {
        protocol: "https://didcomm.org/issue-credential/1.0/",
        startmessage: "offer-credential",
        schema: "RuuJwd3JMffNwZ43DcJKN1:2:Trusted_Traveler:1.4",
    },
}

//{
    //name: "verify-identity",
    //role: "holder",
    //type: "action",
    //data: {
        //protocol: "https://didcomm.org/issue-credential/1.0/",
        //startmessage: "offer-credential",
        //schema: "RuuJwd3JMffNwZ43DcJKN1:2:Trusted_Traveler:1.4",
        //presentation_definition: "http://localhost:3100/api/presentation-exchange"
    //},
    //next: "issue_trusted_traveler"
//}

{

      "next": [
        {
          "issuer-validate-proof": { // Happy path
            "when": [
              "connection_success"
            ]             
          }
        },
        {
          "reject-connection": { // Unhappy path
            "when": "connection_error"           
          }
        }
      ]
    }
}

health-issuer request identity information
holder provide identity information

{
    name: "verify-identity-information",
    role: "health-issuer",
    type: "decision",
    data: {
    
        
        "content": [
              "passport",
              "demographics"
            ]
        
        
        
    },
    next: "collect-credential-information"
}

health-issuer approves identity information
health-issuer collects credential information
health-issuer issues credential
holder accepts credential
holder connects to travel issuer

## Updated and Beautified

{
  "rules-engine": [
      // Holder connects to health_issuer
    {
      "name": "connect-holder-health-issuer",
      "role": [
        "holder"
      ],
      "initial": true,
      "type": "protocol",
      "details": {
        "protocol": "https://didcomm.org/connections/1.0/",
        "startmessage": "invitation"
      },
      "next": {
        "success": "validate-identity-information",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer requests id proof from holder
    {
      "name": "validate-identity-information",
      "role": [
        "issuer"
      ],
      "initial": true,
      "type": "protocol",
      "data": {
        "protocol": "https://didcomm.org/present-proof/1.0/",
        "startmessage": "request-presentation",
        "presentation_definition": "http://localhost:3100/api/presentation-exchange-for-identity-proof"
      },
      "next": {
        "success": "decision-country-of-origin",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer make descision based on an input
    {
      "name": "decision-country-of-origin",
      "role": [
        "issuer"
      ],
      "type": "decision",
      "data": {
        "input_name": "country_of_origin",
        "options": [
          {
            "values": [
              "US",
              "Canada"
            ],
            "next": "reject-country"
          },
          {
            "values": [
              "Germany",
              "Belgium"
            ],
            "next": "select-health-credentials"
          }
        ]
      },
      "next": {
        "success": "select-health-credentials",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer issues health credentials
    {
      "name": "select-health-credentials",
      "role": [
        "issuer"
      ],
      "type": "decision",
      "data": {
        "input_name": "requested_health_credential",
        "options": [
          {
            "values": ["lab_result"],
            "next": "validate-lab-result"
          },
          {
            "values": ["exemption"],
            "next": "validate-exemption"
          },
          {
            "values": ["vaccination"],
            "next": "validate-vaccination"
          }
        ]
      },
        // Do we need a default here? Would/could that be only an error?
      "next": {
        "success": "lab_result",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer issues lab result
    {
      "name": "issue-lab-result",
      "role": [
        "issuer"
      ],
      "type": "protocol",
      "data": {
        "schema": "RuuJwd3JMffNwZ43DcJKN1:2:Lab_Result:1.4",
        "protocol": "https://didcomm.org/issue-credential/1.0/",
        "startmessage": "offer-credential"
      },
      "next": {
        "success": "request-health-proof",
        "error": "some-kind-of-error-handler..."
      }
    },  
      // health_issuer issues issue_exemption
    {
      "name": "issue-exemption",
      "role": [
        "issuer"
      ],
      "type": "protocol",
      "data": {
        "schema": "RuuJwd3JMffNwZ43DcJKN1:2:Exemption:1.4",
        "protocol": "https://didcomm.org/issue-credential/1.0/",
        "startmessage": "offer-credential"
      },
      "next": {
        "success": "request-health-proof",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer issues lab result
    {
      "name": "issue-vaccination",
      "role": [
        "issuer"
      ],
      "type": "protocol",
      "data": {
        "schema": "RuuJwd3JMffNwZ43DcJKN1:2:Vaccination:1.4",
        "protocol": "https://didcomm.org/issue-credential/1.0/",
        "startmessage": "offer-credential"
      },
      "next": {
        "success": "request-health-proof",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer requests lab health proof
    {
      "name": "request-health-proof",
      "role": [
        "issuer"
      ],
      "initial": "true",
      "type": "protocol",
      "data": {
        "protocol": "https://didcomm.org/issue-credential/1.0/",
        "startmessage": "request-presentation",
        "presentation_definition": "http://localhost:3100/api/presentation-exchange"
      },
      "next": {
        "success": "verify-health-credential",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer verifies health credential
    {
      "name": "verify-health-credential",
      "role": [
        "issuer"
      ],
      "type": "protocol",
      "data": {
        "protocol": "https://didcomm.org/present-proof/1.0/",
        "startmessage": "request-presentation",
        "presentation_definition": "http://localhost:3100/api/presentation-exchange"
      },
      "next": {
        "success": "validate-health-credential",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer validates health credential
    {
      "name": "validate-health-credential",
      "role": [
        "issuer"
      ],
      "type": "protocol",
      "data": {
        "presentation_definition": "http://localhost:3100/api/presentation-exchange"
      },
      "next": {
        "success": "issue-trusted-traveler",
        "error": "some-kind-of-error-handler..."
      }
    },
      // health_issuer issues trusted traveler
    {
      "name": "issue-trusted-traveler",
      "role": [
        "issuer"
      ],
      "initial": "true",
      "type": "protocol",
      "data": {
        "protocol": "https://didcomm.org/issue-credential/1.0/",
        "startmessage": "offer-credential",
        "schema": "RuuJwd3JMffNwZ43DcJKN1:2:Trusted_Traveler:1.4"
      }
    },
      // health_issuer rejects country of origin
      // Should we reject country with an error or something else?
    {
      "name": "reject-country",
      "role": [
        "travel-issuer"
      ],
      "type": "protocol",
      "data": {
        "protocol": "https://didcomm.org/basic-message/1.0/",
        "startmessage": "send-message",
        "content": "We're sorry, your country is not approved for entry by the government of Aruba"
      }
    },
    {
      "name": "submit-payment",
      "role": [
        "point-of-sale"
      ],
      "type": "api",
      "data": {
        "api": "https://paymentmagic.com",
        "method": "POST",
        "attributes": [
          "customer_name",
          "customer_date_of_birth",
          "customer_billing_address",
          "customer_shipping_address",
          "credit_card_number",
          "credit_card_expiration",
          "credit_card_security_code"
        ]
      }
    },
  ]
}