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

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

model User {
  id        BigInt   @id @default(autoincrement())
  phone     String   @unique @db.VarChar(32)
  nickname  String?  @db.VarChar(100)
  avatarUrl String?  @map("avatar_url") @db.VarChar(512)
  status    Int      @default(1) @db.SmallInt
  createdAt DateTime @default(now()) @map("created_at")
  updatedAt DateTime @updatedAt @map("updated_at")

  sessions ChatSession[]

  @@map("users")
}

model ChatSession {
  id        BigInt   @id @default(autoincrement())
  userId    BigInt   @map("user_id")
  user      User     @relation(fields: [userId], references: [id], onDelete: Cascade)
  title     String?  @db.VarChar(200)
  messages  ChatMessage[]
  createdAt DateTime @default(now()) @map("created_at")
  updatedAt DateTime @updatedAt @map("updated_at")

  @@index([userId])
  @@map("chat_sessions")
}

model ChatMessage {
  id          BigInt      @id @default(autoincrement())
  sessionId   BigInt      @map("session_id")
  session     ChatSession @relation(fields: [sessionId], references: [id], onDelete: Cascade)
  role        String      @db.VarChar(20)
  content     String      @db.Text
  tokenCount  Int         @default(0) @map("token_count")
  provider    String?     @db.VarChar(64)
  createdAt   DateTime    @default(now()) @map("created_at")

  @@index([sessionId])
  @@map("chat_messages")
}