// This is your Prisma schema file,
// learn more about it in the docs: https://pris.ly/d/prisma-schema

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

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

// ============================================
// User Management
// ============================================

model Role {
  id          Int      @id @default(autoincrement())
  code        String   @unique @db.VarChar(50)
  name        Json     // { th: "", en: "" }
  description Json?
  created_at  DateTime @default(now())
  updated_at  DateTime @updatedAt

  users User[]

  @@map("roles")
}

model User {
  id         Int      @id @default(autoincrement())
  username   String   @unique @db.VarChar(50)
  email      String   @unique @db.VarChar(255)
  password   String   @db.VarChar(255)
  role_id    Int
  is_active  Boolean  @default(true)
  created_at DateTime @default(now())
  updated_at DateTime @updatedAt

  role    Role     @relation(fields: [role_id], references: [id])
  profile Profile?

  // Relations
  created_courses      Course[]           @relation("CourseCreator")
  instructor_courses   CourseInstructor[]
  enrollments          Enrollment[]
  lesson_progress      LessonProgress[]
  quiz_attempts        QuizAttempt[]
  certificates         Certificate[]

  @@index([email])
  @@index([role_id])
  @@map("users")
}

model Profile {
  id          Int       @id @default(autoincrement())
  user_id     Int       @unique
  first_name  String?   @db.VarChar(100)
  last_name   String?   @db.VarChar(100)
  phone       String?   @db.VarChar(20)
  avatar_url  String?   @db.VarChar(500)
  bio         Json?     // { th: "", en: "" }
  birth_date  DateTime?
  created_at  DateTime  @default(now())
  updated_at  DateTime  @updatedAt

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

  @@map("profiles")
}

// ============================================
// Course Management
// ============================================

enum CourseStatus {
  DRAFT
  PENDING_APPROVAL
  APPROVED
  REJECTED
  ARCHIVED
}

model Category {
  id          Int      @id @default(autoincrement())
  code        String   @unique @db.VarChar(50)
  name        Json     // { th: "", en: "" }
  description Json?
  icon_url    String?  @db.VarChar(500)
  is_active   Boolean  @default(true)
  created_at  DateTime @default(now())
  updated_at  DateTime @updatedAt

  courses Course[]

  @@map("categories")
}

model Course {
  id                Int          @id @default(autoincrement())
  title             Json         // { th: "", en: "" }
  description       Json
  thumbnail_url     String?      @db.VarChar(500)
  price             Decimal      @default(0) @db.Decimal(10, 2)
  is_free           Boolean      @default(false)
  have_certificate  Boolean      @default(false)
  status            CourseStatus @default(DRAFT)
  category_id       Int
  created_by        Int
  rejection_reason  String?      @db.Text
  is_deleted        Boolean      @default(false)
  deleted_at        DateTime?
  created_at        DateTime     @default(now())
  updated_at        DateTime     @updatedAt

  category    Category               @relation(fields: [category_id], references: [id])
  creator     User                   @relation("CourseCreator", fields: [created_by], references: [id])
  chapters    Chapter[]
  instructors CourseInstructor[]
  enrollments Enrollment[]

  @@index([category_id])
  @@index([status])
  @@index([created_by])
  @@index([created_at])
  @@map("courses")
}

model CourseInstructor {
  id         Int      @id @default(autoincrement())
  course_id  Int
  user_id    Int
  is_primary Boolean  @default(false)
  created_at DateTime @default(now())

  course Course @relation(fields: [course_id], references: [id], onDelete: Cascade)
  user   User   @relation(fields: [user_id], references: [id], onDelete: Cascade)

  @@unique([course_id, user_id])
  @@index([course_id])
  @@index([user_id])
  @@map("course_instructors")
}

model Chapter {
  id          Int      @id @default(autoincrement())
  course_id   Int
  title       Json     // { th: "", en: "" }
  description Json?
  order       Int
  created_at  DateTime @default(now())
  updated_at  DateTime @updatedAt

  course  Course   @relation(fields: [course_id], references: [id], onDelete: Cascade)
  lessons Lesson[]

  @@index([course_id])
  @@index([order])
  @@map("chapters")
}

// ============================================
// Lessons
// ============================================

enum LessonType {
  VIDEO
  TEXT
  PDF
  QUIZ
}

model Lesson {
  id             Int        @id @default(autoincrement())
  chapter_id     Int
  title          Json       // { th: "", en: "" }
  description    Json?
  type           LessonType
  content        Json?      // For TEXT type
  video_url      String?    @db.VarChar(500)
  video_duration Int?       // in seconds
  order          Int
  is_preview     Boolean    @default(false)
  created_at     DateTime   @default(now())
  updated_at     DateTime   @updatedAt

  chapter      Chapter            @relation(fields: [chapter_id], references: [id], onDelete: Cascade)
  attachments  Attachment[]
  prerequisites LessonPrerequisite[] @relation("LessonPrerequisites")
  required_for LessonPrerequisite[] @relation("RequiredForLessons")
  quiz         Quiz?
  progress     LessonProgress[]

  @@index([chapter_id])
  @@index([order])
  @@map("lessons")
}

model LessonPrerequisite {
  id                  Int      @id @default(autoincrement())
  lesson_id           Int
  prerequisite_lesson_id Int
  created_at          DateTime @default(now())

  lesson              Lesson @relation("LessonPrerequisites", fields: [lesson_id], references: [id], onDelete: Cascade)
  prerequisite_lesson Lesson @relation("RequiredForLessons", fields: [prerequisite_lesson_id], references: [id], onDelete: Cascade)

  @@unique([lesson_id, prerequisite_lesson_id])
  @@index([lesson_id])
  @@index([prerequisite_lesson_id])
  @@map("lesson_prerequisites")
}

model Attachment {
  id           Int      @id @default(autoincrement())
  lesson_id    Int
  filename     String   @db.VarChar(255)
  original_name String  @db.VarChar(255)
  file_url     String   @db.VarChar(500)
  file_size    BigInt
  mime_type    String   @db.VarChar(100)
  created_at   DateTime @default(now())

  lesson Lesson @relation(fields: [lesson_id], references: [id], onDelete: Cascade)

  @@index([lesson_id])
  @@map("attachments")
}

// ============================================
// Quiz System
// ============================================

enum ScorePolicy {
  HIGHEST
  LATEST
  AVERAGE
}

model Quiz {
  id             Int         @id @default(autoincrement())
  lesson_id      Int         @unique
  title          Json        // { th: "", en: "" }
  description    Json?
  passing_score  Int         @default(70)
  time_limit     Int?        // in minutes
  max_attempts   Int         @default(3)
  cooldown_hours Int         @default(24)
  score_policy   ScorePolicy @default(HIGHEST)
  shuffle_questions Boolean  @default(true)
  shuffle_choices   Boolean  @default(true)
  created_at     DateTime    @default(now())
  updated_at     DateTime    @updatedAt

  lesson    Lesson         @relation(fields: [lesson_id], references: [id], onDelete: Cascade)
  questions QuizQuestion[]
  attempts  QuizAttempt[]

  @@map("quizzes")
}

model QuizQuestion {
  id         Int      @id @default(autoincrement())
  quiz_id    Int
  question   Json     // { th: "", en: "" }
  choices    Json     // [{ th: "", en: "", is_correct: boolean }]
  points     Int      @default(1)
  order      Int
  created_at DateTime @default(now())
  updated_at DateTime @updatedAt

  quiz Quiz @relation(fields: [quiz_id], references: [id], onDelete: Cascade)

  @@index([quiz_id])
  @@index([order])
  @@map("quiz_questions")
}

model QuizAttempt {
  id            Int      @id @default(autoincrement())
  quiz_id       Int
  user_id       Int
  answers       Json     // [{ question_id: int, choice_index: int }]
  score         Int
  passed        Boolean
  time_spent    Int?     // in seconds
  started_at    DateTime
  completed_at  DateTime @default(now())

  quiz Quiz @relation(fields: [quiz_id], references: [id], onDelete: Cascade)
  user User @relation(fields: [user_id], references: [id], onDelete: Cascade)

  @@index([quiz_id])
  @@index([user_id])
  @@index([completed_at])
  @@map("quiz_attempts")
}

// ============================================
// Progress Tracking
// ============================================

model Enrollment {
  id              Int       @id @default(autoincrement())
  user_id         Int
  course_id       Int
  enrolled_at     DateTime  @default(now())
  completed_at    DateTime?
  progress_percent Int      @default(0)
  last_accessed_at DateTime @default(now())

  user   User   @relation(fields: [user_id], references: [id], onDelete: Cascade)
  course Course @relation(fields: [course_id], references: [id], onDelete: Cascade)

  @@unique([user_id, course_id])
  @@index([user_id])
  @@index([course_id])
  @@map("enrollments")
}

model LessonProgress {
  id              Int       @id @default(autoincrement())
  user_id         Int
  lesson_id       Int
  is_completed    Boolean   @default(false)
  video_progress  Int       @default(0) // seconds watched
  completed_at    DateTime?
  last_watched_at DateTime  @default(now())
  created_at      DateTime  @default(now())
  updated_at      DateTime  @updatedAt

  user   User   @relation(fields: [user_id], references: [id], onDelete: Cascade)
  lesson Lesson @relation(fields: [lesson_id], references: [id], onDelete: Cascade)

  @@unique([user_id, lesson_id])
  @@index([user_id])
  @@index([lesson_id])
  @@map("lesson_progress")
}

model Certificate {
  id          Int      @id @default(autoincrement())
  user_id     Int
  course_id   Int
  certificate_url String @db.VarChar(500)
  issued_at   DateTime @default(now())

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

  @@unique([user_id, course_id])
  @@index([user_id])
  @@map("certificates")
}