React Js, Next Js Technology Upgradation (R&D)

This major feature implementation allows the CaxiAIQuote agent to successfully process, search, and display complex multi-leg itineraries (e.g., A → B → C → A) without crashing or relying on round-trip logic.

This required architectural changes across all layers of the application, replacing single-route variables with array-based segment handling.

Implementation Details by Phase (Full Flow)
Phase 1: AI Extraction and Validation (aiProcessor.js, aiSchema.js)
Schema Update: Added TripType: "Multicity" to the enum and introduced the Segments array property.

AI Logic: Updated validateParams to branch: if TripType is 'Multicity', it enforces Segments array validation instead of checking Source/Destination.

Data Consolidation: Logic added to search segments for SeatClass and promote it to the top level for consistency in API calls.

Date Handling: Confirmed rolling year and date parsing logic applies correctly to each segment's DepartureDate.

Phase 2: API Payload Construction (payloadBuilder.js)
SearchType: Logic updated to set SearchConfig.SearchType = 3 if TripType is 'Multicity'.

Dynamic Journeys: Replaced fixed outboundJourney/returnJourney construction with a dynamic loop that iterates through the aiParams.Segments array.

Location Mapping: Called mapToIata for every segment's Source and Destination.

Airline: Airline codes are passed as an empty array to the API, maintaining local filtering responsibility.

Phase 3: Deep Link Generation (urlBuilder.js)
URL Path: Implemented multicity route building. If TripType is 'MultiCity', the URL path is dynamically generated by resolving and concatenating all segment routes with an underscore:

Example: .../MultiCity/DEL-BKK-05Feb2026_BKK-ICN-10Feb2026/...

Phase 4: Filtering and Display (filterService.js, htmlGenerator.js)
Summary Display: renderSearchSummary was updated to recognize Multicity and display the full route path (e.g., "DEL ➝ BKK ➝ ICN ➝ DEL") and date range correctly.

Trip Card Layout: renderTripCard uses the existing trip.FlightJourneys loop, which naturally displays multi-leg flights. A visual separator was added between internal journeys for clarity.

Filter Application: Logic confirmed in filterService.js that stop/time/airline filtering applies against all segments within a multicity itinerary.

Verification Steps (Test Plan)
API Test (/api/debug/analyze-flow): Use the prompt: "fly across three cities: Delhi to Bangkok Feb 5, Bangkok to Seoul Feb 10, Seoul to Delhi Feb 16, Business Class."

Expected Output: TripType must be "Multicity". SearchConfig.SearchType must be 3. Journeys array must contain 3 objects.

UI Test (/search): Submit the same prompt.

Expected HTML: The summary box should show the full route (DEL ➝ BKK ➝ SEOUL ➝ DEL) and the correct date range. The flight cards should display multiple journeys separated by a dashed line.