// Domain models

model Group {
  id          String   @id @default(cuid())
  name        String
  description String?
  createdById String
  createdAt   DateTime @default(now())
  updatedAt   DateTime @updatedAt

  owner    User          @relation("OwnerGroups", fields: [createdById], references: [id], onDelete: Cascade)
  members  GroupMember[]
  students Student[]
  payments Payment[]

  @@map("groups")
}

model GroupMember {
  id       String @id @default(cuid())
  groupId  String
  userId   String
  role     Role   @default(MEMBER) // OWNER, ADMIN, MEMBER
  joinedAt DateTime @default(now())

  group Group @relation(fields: [groupId], references: [id], onDelete: Cascade)
  user  User  @relation(fields: [userId], references: [id], onDelete: Cascade)

  @@unique([groupId, userId])
  @@map("group_members")
}

enum Role {
  OWNER
  ADMIN
  MEMBER
}

model Student {
  id             String   @id @default(cuid())
  groupId        String
  fullName       String
  email          String?
  phone          String?
  guardianName   String?
  guardianPhone  String?
  notes          String?
  createdAt      DateTime @default(now())
  updatedAt      DateTime @updatedAt

  group    Group    @relation(fields: [groupId], references: [id], onDelete: Cascade)
  payments Payment[]

  @@index([groupId])
  @@map("students")
}

model Payment {
  id        String        @id @default(cuid())
  groupId   String
  studentId String
  amount    Decimal       @db.Decimal(10, 2)
  currency  String        @default("MXN")
  status    PaymentStatus @default(PENDING) // PENDING, PAID, OVERDUE, CANCELLED
  dueDate   DateTime
  paidAt    DateTime?
  createdAt DateTime      @default(now())
  updatedAt DateTime      @updatedAt

  group   Group   @relation(fields: [groupId], references: [id], onDelete: Cascade)
  student Student @relation(fields: [studentId], references: [id], onDelete: Cascade)

  @@index([groupId])
  @@index([studentId])
  @@map("payments")
}

enum PaymentStatus {
  PENDING
  PAID
  OVERDUE
  CANCELLED
}

model WaitlistEntry {
  id        String        @id @default(cuid())
  email     String
  name      String?
  status    WaitlistStatus @default(PENDING) // PENDING, INVITED, JOINED, DECLINED
  createdAt DateTime      @default(now())
  updatedAt DateTime      @updatedAt

  userId String? @unique

  user User? @relation(fields: [userId], references: [id], onDelete: SetNull)

  @@unique([email])
  @@map("waitlist_entries")
}

enum WaitlistStatus {
  PENDING
  INVITED
  JOINED
  DECLINED
}