[Customer Portal][BE] Add AI chat agent for case classification during creation

apps/customer-portal/backend/config.toml.local

@@ -24,3 +24,11 @@ updatesServiceUrl = "<base_url>"
     clientId = "<client_id>"
     clientSecret = "<client_secret>"
     scopes = ["<scopes>"]
+
+[customer_portal.ai_chat_agent]
+aiChatAgentBaseUrl = "<base_url>"
+[customer_portal.updates.clientCredentialsOauth2Config]
+    tokenUrl = "<token_url>"
+    clientId = "<client_id>"
+    clientSecret = "<client_secret>"
+    scopes = ["<scopes>"]

apps/customer-portal/backend/modules/ai_chat_agent/ai_chat_agent.bal

@@ -0,0 +1,25 @@
+// Copyright (c) 2026 WSO2 LLC. (https://www.wso2.com).
+//
+// WSO2 LLC. licenses this file to you under the Apache License,
+// Version 2.0 (the "License"); you may not use this file except
+// in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+# Get case classification for the given payload.
+#
+# + payload - Case classification payload
+# + return - Case classification response or error
+public isolated function createCaseClassification(CaseClassificationPayload payload)
+    returns CaseClassificationResponse|error {
+
+    return aiChatAgentClient->/case_classification.post(payload);
+}

apps/customer-portal/backend/modules/ai_chat_agent/client.bal

@@ -0,0 +1,37 @@
+// Copyright (c) 2026 WSO2 LLC. (https://www.wso2.com).
+//
+// WSO2 LLC. licenses this file to you under the Apache License,
+// Version 2.0 (the "License"); you may not use this file except
+// in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+import ballerina/http;
+
+configurable string aiChatAgentBaseUrl = ?;
+configurable ClientCredentialsOauth2Config clientCredentialsOauth2Config = ?;
+
+final http:Client aiChatAgentClient = check new (aiChatAgentBaseUrl, {
+    auth: {
+        ...clientCredentialsOauth2Config
+    },
+    httpVersion: http:HTTP_1_1,
+    http1Settings: {keepAlive: http:KEEPALIVE_NEVER},
+    timeout: 300.0,
+    retryConfig: {
+        count: 3,
+        interval: 2.0,
+        statusCodes: [
+            http:STATUS_BAD_GATEWAY,
+            http:STATUS_SERVICE_UNAVAILABLE,
+            http:STATUS_GATEWAY_TIMEOUT
+        ]
+    }
+});

apps/customer-portal/backend/modules/ai_chat_agent/types.bal

@@ -0,0 +1,73 @@
+// Copyright (c) 2026 WSO2 LLC. (https://www.wso2.com).
+//
+// WSO2 LLC. licenses this file to you under the Apache License,
+// Version 2.0 (the "License"); you may not use this file except
+// in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+import ballerina/data.jsondata;
+
+# [Configurable] Client credentials grant type oauth2 configuration.
+type ClientCredentialsOauth2Config record {|
+    # OAuth2 token endpoint
+    string tokenUrl;
+    # OAuth2 client ID
+    string clientId;
+    # OAuth2 client secret
+    string clientSecret;
+    # OAuth2 scopes
+    string[] scopes = [];
+|};
+
+# Case classification payload.
+public type CaseClassificationPayload record {|
+    # Chat history
+    string chat_history;
+    # Product details
+    string[] productDetails;
+    # Environments
+    string[] environments;
+    # Region
+    string region;
+    # Tier
+    string tier;
+|};
+
+# Case classification response.
+public type CaseClassificationResponse record {|
+    # Issue type
+    string issueType;
+    # Case information
+    @jsondata:Name {value: "case_info"}
+    ChatCaseInfo caseInfo;
+    # Severity level
+    string severityLevel;
+    json...;
+|};
+
+# Chat case information.
+public type ChatCaseInfo record {|
+    # Description
+    string description;
+    # Short description
+    string shortDescription;
+    # Product name
+    string productName;
+    # Product version
+    string productVersion;
+    # Environment
+    string environment;
+    # Tier
+    string tier;
+    # Region
+    string region;
+    json...;
+|};

apps/customer-portal/backend/service.bal

@@ -14,6 +14,7 @@
 // specific language governing permissions and limitations
 // under the License.
 
+import customer_portal.ai_chat_agent;
 import customer_portal.authorization;
 import customer_portal.entity;
 import customer_portal.scim;
@@ -829,6 +830,44 @@ service http:InterceptableService / on new http:Listener(9090) {
         return getCaseFilters(caseMetadata);
     }
 
+    # Classify the case using AI chat agent.
+    #
+    # + payload - case classification payload
+    # + return - Case classification response or an error
+    resource function post cases/classification(http:RequestContext ctx, CaseClassificationPayload payload)
+        returns ai_chat_agent:CaseClassificationResponse|http:InternalServerError {
+
+        authorization:UserInfoPayload|error userInfo = ctx.getWithType(authorization:HEADER_USER_INFO);
+        if userInfo is error {
+            return <http:InternalServerError>{
+                body: {
+                    message: ERR_MSG_USER_INFO_HEADER_NOT_FOUND
+                }
+            };
+        }
+
+        // TODO: Need to persist the chat history
+        ai_chat_agent:CaseClassificationResponse|error classificationResponse =
+            ai_chat_agent:createCaseClassification(
+                {
+                    chat_history: payload.chatHistory,
+                    productDetails: payload.productDetails,
+                    environments: payload.environments,
+                    region: payload.region,
+                    tier: payload.tier
+                });
+        if classificationResponse is error {
+            string customError = "Failed to classify chat message.";
+            log:printError(customError, classificationResponse);
+            return <http:InternalServerError>{
+                body: {
+                    message: customError
+                }
+            };
+        }
+        return classificationResponse;
+    }
+
     # Get comments for a specific case.
     #
     # + id - ID of the case

apps/customer-portal/backend/types.bal

@@ -309,3 +309,17 @@ public type AttachmentPayload record {|
     # Base 64 encoded content
     string content;
 |};
+
+# Case classification payload.
+public type CaseClassificationPayload record {|
+    # Chat history
+    string chatHistory;
+    # Product details
+    string[] productDetails;
+    # Environments
+    string[] environments;
+    # Region
+    string region;
+    # Tier
+    string tier;
+|};