generator client {
  provider = "prisma-client-js"
}

datasource db {
  provider = "sqlite"
  url      = env("DATABASE_URL")
}

model Vendor {
  id           String   @id @default(cuid())
  name         String
  businessNum  String?
  taxSettings  String?  // JSON string
  createdAt    DateTime @default(now())
  updatedAt    DateTime @updatedAt

  users        User[]
  categories   Category[]
  products     Product[]
  taxes        Tax[]
  transactions Transaction[]
  events       Event[]
}

model Role {
  id    String @id @default(cuid())
  name  String @unique // admin | vendor | user

  users User[]
}

model User {
  id           String   @id @default(cuid())
  email        String   @unique
  passwordHash String
  name         String
  vendorId     String
  roleId       String
  createdAt    DateTime @default(now())
  updatedAt    DateTime @updatedAt

  vendor        Vendor         @relation(fields: [vendorId], references: [id])
  role          Role           @relation(fields: [roleId], references: [id])
  refreshTokens RefreshToken[]
  transactions  Transaction[]
}

model RefreshToken {
  id        String   @id @default(cuid())
  token     String   @unique
  userId    String
  expiresAt DateTime
  createdAt DateTime @default(now())

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

model Category {
  id        String   @id @default(cuid())
  name      String
  vendorId  String
  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt

  vendor   Vendor    @relation(fields: [vendorId], references: [id])
  products Product[]
}

model Tax {
  id        String   @id @default(cuid())
  name      String
  rate      Float
  vendorId  String
  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt

  vendor         Vendor     @relation(fields: [vendorId], references: [id])
  products       Product[]
  eventOverrides EventTax[]
}

model Product {
  id          String   @id @default(cuid())
  name        String
  sku         String?
  description String?
  price       Float
  vendorId    String
  categoryId  String?
  taxId       String?
  tags        String?  // comma-separated or JSON string
  version     Int      @default(1)
  createdAt   DateTime @default(now())
  updatedAt   DateTime @updatedAt

  vendor           Vendor            @relation(fields: [vendorId], references: [id])
  category         Category?         @relation(fields: [categoryId], references: [id])
  tax              Tax?              @relation(fields: [taxId], references: [id])
  transactionItems TransactionItem[]
  eventProducts    EventProduct[]
}

model Transaction {
  id             String   @id @default(cuid())
  idempotencyKey String   @unique
  vendorId       String
  userId         String
  eventId        String?
  status         String   // pending | completed | failed | refunded
  paymentMethod  String   // cash | card
  subtotal       Float
  taxTotal       Float
  discountTotal  Float
  total          Float
  notes          String?
  createdAt      DateTime @default(now())
  updatedAt      DateTime @updatedAt

  vendor Vendor            @relation(fields: [vendorId], references: [id])
  user   User              @relation(fields: [userId], references: [id])
  event  Event?            @relation(fields: [eventId], references: [id])
  items  TransactionItem[]
}

model TransactionItem {
  id            String @id @default(cuid())
  transactionId String
  productId     String
  productName   String
  quantity      Int
  unitPrice     Float
  taxRate       Float
  discount      Float
  total         Float

  transaction Transaction @relation(fields: [transactionId], references: [id])
  product     Product     @relation(fields: [productId], references: [id])
}

// ─── Events ───────────────────────────────────────────────────────────────────

model Event {
  id          String   @id @default(cuid())
  vendorId    String
  name        String
  description String?
  startsAt    DateTime
  endsAt      DateTime
  isActive    Boolean  @default(true)
  createdAt   DateTime @default(now())
  updatedAt   DateTime @updatedAt

  vendor       Vendor         @relation(fields: [vendorId], references: [id])
  taxOverrides EventTax[]
  products     EventProduct[]
  transactions Transaction[]
}

// Tax rate overrides for a specific event. Shadows the vendor-level Tax for the
// event duration. Empty = use vendor defaults.
model EventTax {
  id      String @id @default(cuid())
  eventId String
  taxId   String
  rate    Float  // override rate in percent

  event Event @relation(fields: [eventId], references: [id], onDelete: Cascade)
  tax   Tax   @relation(fields: [taxId], references: [id])

  @@unique([eventId, taxId])
}

// Allowlist of products available at an event. Empty = all vendor products available.
model EventProduct {
  id        String @id @default(cuid())
  eventId   String
  productId String

  event   Event   @relation(fields: [eventId], references: [id], onDelete: Cascade)
  product Product @relation(fields: [productId], references: [id])

  @@unique([eventId, productId])
}