Improve insurance integration stability & prevent unnecessary reloading of widget

[olance]

Reason for change

In some versions of PrestaShop (here, 1.7.2.4), the insurance widget is reloaded in an infinite loop:

Enregistrement.de.l.ecran.2024-10-23.a.21.16.35.mov

In some other versions (e.g. 1.7.0.6) the reloading only inexplicably happens once instead of infinitely, i.e. 2 consecutive loading of the widget, so 1 extra load.

The root cause for both seems to be the use of PrestaShop events paired with messaging management from the widget iframe.

As a side effect, the whole product details & add to cart section of the product page is reloaded unnecessarily, including our BNPL widget, which makes the sidebar's height jump up & down.

Fixes ECOM-2184

Code changes

• Started by documenting existing code to better grasp its inner workings
• Then simplified it and refactored the control flow to isolate the code handling prestashop-initiated events from widget-initiated events. This way we only listen to prestashop events to trigger necessary refreshes, and handle widget events without reloading the PrestaShop UI unnecessarily.

How to test

As a reviewer, you are encouraged to test the PR locally.

Before making the present changes, I noted different behaviours/bugs depending on different PS versions:

• 1.7.0.6
• 1.7.2.4
• 1.7.8.7

With this PR, the integration should behave the same in all versions and the following issues should not be visible anymore:

• Insurance modale not always showing on add to cart event:
  • Click on an insurance option in the widget: the modal opens up
  • Close the modal by choosing "I don't want to protect my purchase"
  • Click on "Add to cart": ❌ the modal does not open and the product is added to the cart immediately
• Initial load of the widget happens twice:
  • Open the page of an eligible product
  • ❌ The widget is displayed, and then reloaded once
    • This is noticeable as the BNPL widget will "blink" and the height of the right section thus changes temporarily
    • On PS 1.7.2.4, because of a different reloading behaviour from PS, the reload loop is infinite as seen on the above video
• The modal sometimes "ignores" the quantity > 1:
  • Increase the quantity wanted for a product
  • Click on an insurance option in the widget (the bug does not show when clicking Add to Cart)
  • Click on "Protect my purchase" in the modal
    • ❌ The modal closes without offering to protect one or multiple products, despite the quantity being > 1

Checklist for authors and reviewers

• The title of the PR uses business wording, not technical jargon, for the changelog readers to understand it
• The PR implements the changes asked in the referenced task / issue
• You understand the impact of this PR on existing code/features

Non applicable

• The automated tests are compliant with the testing strategy
• The tests are relevant, and cover the corner/error cases, not only the happy path
• The changes include adequate logging and Datadog traces
• Documentation is updated (API, developer documentation, ADR, Notion...)

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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[github-actions]

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