Installations App
=================

**Purpose**: Manage installation scheduling, material readiness, charger installation execution, demo, and report submission.

Responsibilities
----------------

- Create installations from approved surveys
- Generate human-readable Installation IDs (e.g., ``INS-2026-00456``)
- Coordinate with Procurement for material readiness
- Schedule installation date and time slot
- Assign field teams to installations
- Track pre-installation customer confirmation
- Capture installation reports (charger serial, model, success status, demo sign-off)
- Capture installation media (photos, videos)

Dependencies
------------

- **surveys** — Installation is linked to an approved Survey (OneToOne)
- **leads** — Back-reference to the originating lead
- **accounts** — Field team assignment, Central Ops planner
- **procurement** — Material allocation check
- **emergency** — Triggered when assigned team is unavailable
- **notifications** — Confirmation calls and reminders

Key Models
----------

- **Installation** — Scheduled installation linked to a survey. Tracks material readiness, customer confirmation, demo completion.
- **InstallationAssignment** — Links an installation to a field team. Supports primary and emergency backup.
- **InstallationReport** — Post-installation record: charger serial number, model, success flag, customer signature, issues encountered.
- **InstallationMedia** — Photos and videos of the completed installation.

Status Lifecycle
----------------

.. code-block:: text

   planned → material_pending → material_ready → confirmed →
   in_progress → completed → report_submitted → closed

   Any state → rescheduled
   Any state → cancelled

Business Rules
--------------

- An installation can only be created from a survey with ``reviewed_approved`` status.
- Installation cannot proceed to ``confirmed`` until ``material_ready`` is True.
- Customer pre-installation confirmation is required before moving to ``in_progress``.
- Installation report must include charger serial number and model.
- Demo completion is tracked but not blocking for report submission.
- Customer signature (digital or photo) is strongly recommended but not mandatory.