fix: session calendar month navigation not working on course detail page

[abdulateeb]

Related issues

Fixes #902

Checklist

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Problem

The session calendar's previous/next month navigation buttons on the course detail page did not work. Clicking the left or right arrows had no visible effect - the calendar remained stuck on the current month.

Solution

• Added onclick handlers: The previous/next month buttons now have initial onclick handlers using Django template variables, so they work on first page load
• Fixed fetch URL: Changed from a hardcoded path (/courses/.../calendar/) to Django's {% url %} template tag, which correctly includes the /en/ language prefix and prevents silent 404 errors

Screenshots

view attached screen recording as it shows before and after

calendar_issue_fix.mp4

Summary by CodeRabbit

• Refactor
  • Improved the calendar navigation system to use more robust URL handling, ensuring calendar views load correctly when navigating between months.

[coderabbitai]

Walkthrough

The changes add inline onclick event handlers to calendar navigation buttons and update the calendar data fetch URL to use Django's URL reversal instead of a hard-coded path in the courses detail template.

Changes

Cohort / File(s)	Summary
Calendar Navigation and URL Updates web/templates/courses/detail.html	Added onclick handlers to prev-month-btn and next-month-btn to call loadCalendar() with appropriate month/year parameters. Updated calendar fetch URL from hard-coded path to Django URL reversal using {% url 'course_calendar' course.slug %}.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Possibly related issues

• Issue #902: Calendar navigation behavior changes directly address the onclick handler integration and Django URL reversal described in this issue.

Possibly related PRs

• PR #302: Both PRs modify calendar-related JavaScript implementation and invocation in web/templates/courses/detail.html.

Suggested labels

d4

Suggested reviewers

• A1L13N

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main fix: restoring month navigation functionality for the session calendar on the course detail page.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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[Copilot]

Pull request overview

This PR fixes a bug where the session calendar's previous/next month navigation buttons on the course detail page were non-functional. The issue was caused by missing initial onclick handlers and an incorrect hardcoded fetch URL that didn't include the language prefix.

Changes:

• Added initial onclick handlers to prev/next month buttons using Django template variables for the year and month values
• Fixed the fetch URL in loadCalendar() function to use Django's {% url %} template tag instead of a hardcoded path, ensuring the language prefix is included

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@web/templates/courses/detail.html`:
- Around line 444-454: Replace the inline onclick attributes on the prev/next
buttons in the template (elements with ids prev-month-btn and next-month-btn)
with data-year and data-month attributes initialized from {{ prev_month }} / {{
next_month }}, remove any code that calls setAttribute to update onclick, and
instead add a one-time DOM event listener that calls the existing
loadCalendar(year, month) using parseInt(this.dataset.year) and
parseInt(this.dataset.month); update the part of the JS that currently updates
onclick (in loadCalendar's response handling) to set dataset.year/dataset.month
on the two buttons (or reconstruct them from response.prev_month/next_month)
rather than changing onclick strings.