Accounts Models

User

Extends Django’s AbstractUser to add phone, role, zone, and availability tracking.

Field	Type	Constraints	Description
id	UUIDField	PK, default=uuid4	Primary key
username	CharField(150)	unique, not null	Inherited from AbstractUser
email	EmailField	unique, nullable	User email address
phone	CharField(15)	unique, not null	Primary contact number
role	ForeignKey(Role)	not null, on_delete=PROTECT	User’s system role
zone	ForeignKey(Zone)	nullable, on_delete=SET_NULL	Geographic zone assignment (required for field_team)
is_available	BooleanField	default=True	Current availability for field assignments
created_at	DateTimeField	auto_now_add	Account creation timestamp
updated_at	DateTimeField	auto_now	Last modification timestamp

Indexes: phone, role, zone, is_available

Role

Defines the seven system roles. Uses Django’s permission framework for granular access control.

Field	Type	Constraints	Description
id	AutoField	PK	Primary key
name	CharField(50)	unique, choices	One of: oem, customer, central_ops, field_team, procurement, finance, oem_reporting
description	TextField	blank	Human-readable role description
permissions	ManyToManyField(Permission)	blank	Django permissions associated with this role

Team

Groups of field team users operating within a geographic zone.

Field	Type	Constraints	Description
id	UUIDField	PK, default=uuid4	Primary key
name	CharField(100)	not null	Team display name
zone	ForeignKey(Zone)	not null, on_delete=PROTECT	Operating zone
team_type	CharField(20)	choices: survey, installation, both	Team specialization
is_active	BooleanField	default=True	Whether team is operational

Indexes: zone, team_type, is_active

TeamMembership

Join table linking users to teams with a position.

Field	Type	Constraints	Description
id	AutoField	PK	Primary key
user	ForeignKey(User)	not null, on_delete=CASCADE	Team member
team	ForeignKey(Team)	not null, on_delete=CASCADE	Team
role_in_team	CharField(20)	choices: lead, member	Position within team
joined_at	DateTimeField	auto_now_add	When user joined the team

Unique constraint: (user, team)

Zone

Geographic service areas that scope teams, stock, and vendor availability.

Field	Type	Constraints	Description
id	AutoField	PK	Primary key
name	CharField(100)	unique, not null	Zone name (city/district)
state	CharField(100)	not null	State/province
is_active	BooleanField	default=True	Whether zone is currently serviceable