Surveys Models
==============

Survey
------

Represents a scheduled site survey linked to a lead. The survey determines whether the customer's site is ready for charger installation.

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 40

   * - Field
     - Type
     - Constraints
     - Description
   * - id
     - UUIDField
     - PK, default=uuid4
     - Primary key
   * - survey_id
     - CharField(20)
     - unique, auto-generated
     - Human-readable ID (e.g., ``SRV-2026-00123``)
   * - lead
     - OneToOneField(Lead)
     - not null, on_delete=CASCADE
     - Associated lead
   * - scheduled_date
     - DateField
     - not null
     - Planned survey date
   * - scheduled_time_slot
     - CharField(20)
     - choices: ``morning``, ``afternoon``, ``evening``
     - Time window
   * - status
     - CharField(20)
     - choices, default='scheduled'
     - Survey lifecycle state
   * - customer_confirmed
     - BooleanField
     - default=False
     - Customer confirmed availability
   * - created_by
     - ForeignKey(User)
     - not null, on_delete=PROTECT
     - Central Ops who scheduled
   * - created_at
     - DateTimeField
     - auto_now_add
     - Creation timestamp
   * - updated_at
     - DateTimeField
     - auto_now
     - Last update

**Status choices**: ``scheduled``, ``confirmed``, ``in_progress``, ``completed``, ``report_submitted``, ``reviewed_approved``, ``reviewed_rejected``, ``rescheduled``, ``cancelled``

**Indexes**: ``status``, ``scheduled_date``, ``created_by``

SurveyAssignment
----------------

Links a survey to a field team. Supports both primary assignments and emergency backup reassignments.

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 40

   * - Field
     - Type
     - Constraints
     - Description
   * - id
     - UUIDField
     - PK, default=uuid4
     - Primary key
   * - survey
     - ForeignKey(Survey)
     - not null, on_delete=CASCADE
     - Parent survey
   * - team
     - ForeignKey(Team)
     - not null, on_delete=PROTECT
     - Assigned field team
   * - assigned_by
     - ForeignKey(User)
     - not null, on_delete=PROTECT
     - Central Ops who assigned
   * - is_primary
     - BooleanField
     - default=True
     - Primary assignment vs emergency backup
   * - assigned_at
     - DateTimeField
     - auto_now_add
     - Assignment timestamp
   * - status
     - CharField(20)
     - choices: ``assigned``, ``accepted``, ``en_route``, ``on_site``, ``completed``, ``cancelled``
     - Assignment state

SurveyReport
------------

Detailed site assessment submitted by the field team after conducting the survey.

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 40

   * - Field
     - Type
     - Constraints
     - Description
   * - id
     - UUIDField
     - PK, default=uuid4
     - Primary key
   * - survey
     - OneToOneField(Survey)
     - not null, on_delete=CASCADE
     - Parent survey
   * - submitted_by
     - ForeignKey(User)
     - not null, on_delete=PROTECT
     - Field team member who submitted
   * - site_ready
     - BooleanField
     - not null
     - Overall: is the site installation-ready?
   * - load_adequate
     - BooleanField
     - not null
     - Electrical load sufficient for charger
   * - earthing_present
     - BooleanField
     - not null
     - Proper earthing exists at site
   * - civil_work_needed
     - BooleanField
     - default=False
     - Civil work required before installation
   * - civil_work_details
     - TextField
     - blank
     - Description of civil work needed
   * - electrical_notes
     - TextField
     - blank
     - Electrical observations and recommendations
   * - general_notes
     - TextField
     - blank
     - General site observations
   * - reviewed_by
     - ForeignKey(User)
     - nullable, on_delete=SET_NULL
     - Central Ops reviewer
   * - review_status
     - CharField(20)
     - choices: ``pending``, ``approved``, ``rejected``, default='pending'
     - Review outcome
   * - review_notes
     - TextField
     - blank
     - Reviewer comments
   * - submitted_at
     - DateTimeField
     - auto_now_add
     - Submission timestamp
   * - reviewed_at
     - DateTimeField
     - nullable
     - Review timestamp

SurveyMedia
------------

Photos and videos captured during a survey.

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 40

   * - Field
     - Type
     - Constraints
     - Description
   * - id
     - UUIDField
     - PK, default=uuid4
     - Primary key
   * - survey
     - ForeignKey(Survey)
     - not null, on_delete=CASCADE
     - Parent survey
   * - media_type
     - CharField(20)
     - choices: ``photo``, ``video``
     - Media type
   * - file
     - FileField
     - not null, upload_to='survey_media/'
     - Media file
   * - caption
     - CharField(255)
     - blank
     - Description of what the media shows
   * - uploaded_by
     - ForeignKey(User)
     - not null, on_delete=PROTECT
     - Field team member who uploaded
   * - uploaded_at
     - DateTimeField
     - auto_now_add
     - Upload timestamp