/**
 * Prisma Schema for Maternal Health Support Backend
 * ORM CHOICE: Prisma
 * JUSTIFICATION:
 * - Type-safe database client with excellent TypeScript support
 * - Intuitive schema definition language
 * - Automatic migration generation
 * - Built-in connection pooling
 * - Great developer experience with Prisma Studio
 * - Strong PostgreSQL support
 * CLINICAL SAFETY PRINCIPLES:
 * - Data minimization enforced at schema level
 * - No free-text medical fields
 * - Enums for controlled vocabularies
 * - Timestamps for audit trails
 * - Strict validation rules
 */

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

datasource db {
  provider = "postgresql"
}

/**
 * User Role Enum
 */
enum UserRole {
  SUPER_ADMIN
  FACILITY_ADMIN
  FACILITY_STAFF
  PATIENT
}

/**
 * Health Worker Type Enum
 */
enum HealthWorkerType {
  DOCTOR
  NURSE
  MIDWIFE
  COMMUNITY_HEALTH_WORKER
}

enum PatientRiskLevel {
  NORMAL
  HIGH
  CRITICAL
}

/**
 * Organization Entity
 */
model Organization {
  id          String   @id @default(uuid())
  name        String
  description String?
  isActive    Boolean  @default(true)
  createdAt   DateTime @default(now())
  updatedAt   DateTime @updatedAt

  facilities Facility[]

  @@index([isActive])
  @@map("organization")
}

/**
 * Facility Status Enum
 */
enum FacilityStatus {
  PENDING
  ACTIVE
  SUSPENDED
}

/**
 * Facility Entity
 */
model Facility {
  id             String         @id @default(uuid())
  organizationId String?
  name           String
  address        String?
  phone          String?
  facilityCode   String         @unique
  isActive       Boolean        @default(true)
  status         FacilityStatus @default(ACTIVE)
  createdAt      DateTime       @default(now())
  updatedAt      DateTime       @updatedAt

  organization      Organization?       @relation(fields: [organizationId], references: [id], onDelete: Cascade)
  healthcareWorkers HealthcareWorker[]
  patients          Patient[]
  appointments      Appointment[]
  alerts            Alert[]
  referrals         Referral[]
  ancVisits         ANCVisit[]
  outgoingReferrals Referral[]         @relation("OutgoingReferrals")
  incomingReferrals Referral[]         @relation("IncomingReferrals")

  @@index([organizationId])
  @@index([facilityCode])
  @@index([isActive])
  @@map("facility")
}

/**
 * Healthcare Worker Entity
 */
model HealthcareWorker {
  id          String           @id @default(uuid())
  userId      String           @unique
  facilityId  String
  type        HealthWorkerType
  firstName   String
  lastName    String
  isSuspended Boolean          @default(false)
  createdAt   DateTime         @default(now())
  updatedAt   DateTime         @updatedAt

  userAuth UserAuth @relation(fields: [userId], references: [id], onDelete: Cascade)
  facility Facility @relation(fields: [facilityId], references: [id], onDelete: Cascade)

  ancVisits ANCVisit[]

  @@index([userId])
  @@index([facilityId])
  @@index([isSuspended])
  @@map("healthcare_worker")
}

/**
 * Blood Group Enum
 */
enum BloodGroup {
  A_POSITIVE
  A_NEGATIVE
  B_POSITIVE
  B_NEGATIVE
  O_POSITIVE
  O_NEGATIVE
  AB_POSITIVE
  AB_NEGATIVE
}

/**
 * Genotype Enum
 */
enum Genotype {
  AA
  AS
  AC
  SS
  SC
  CC
}

/**
 * Smoking Status Enum
 */
enum SmokingStatus {
  NEVER
  CURRENT
  FORMER
}

/**
 * Alcohol Use Enum
 */
enum AlcoholUse {
  NEVER
  OCCASIONAL
  REGULAR
}

/**
 * Substance Use Enum
 */
enum SubstanceUse {
  NEVER
  CURRENT
  FORMER
}

/**
 * Education Level Enum
 */
enum EducationLevel {
  NONE
  PRIMARY
  SECONDARY
  TERTIARY
}

/**
 * Booking Status Enum
 */
enum BookingStatus {
  BOOKED
  UNBOOKED
}

/**
 * Patient Entity
 */
model Patient {
  id                    String    @id @default(uuid())
  userId                String    @unique
  facilityId            String
  patientId             String    @unique
  firstName             String
  lastName              String
  phone                 String
  age                   Int
  address               String?
  gestationalAge        Int
  estimatedDeliveryDate DateTime?
  qrCode                String?
  isActive              Boolean   @default(true)
  createdAt             DateTime  @default(now())
  updatedAt             DateTime  @updatedAt

  userAuth     UserAuth      @relation(fields: [userId], references: [id], onDelete: Cascade)
  facility     Facility?      @relation(fields: [facilityId], references: [id], onDelete: Cascade)
  appointments Appointment[]
  alerts       Alert[]
  referrals    Referral[]

  ancVisits       ANCVisit[]
  status          PatientStatus    @default(ACTIVE)
  riskLevel       PatientRiskLevel @default(NORMAL)
  riskReason      String?
  latestRiskLevel RiskLevel        @default(LOW)
  lastVisitDate   DateTime?

  // --- Patient Information ---
  bloodGroup              BloodGroup?
  genotype                Genotype?
  emergencyContactName    String?
  emergencyContactPhone   String?
  emergencyContactRelation String?

  // --- Obstetric History ---
  gravidity               Int?       // G
  parity                  Int?       // P
  livingChildren          Int?
  previousMiscarriages    Int?
  previousAbortions       Int?
  previousStillbirths     Int?
  previousNeonatalDeaths  Int?
  previousCaesareans      Int?
  previousMultiplePregnancy Boolean?

  // --- Current Pregnancy ---
  lastMenstrualPeriod     DateTime?
  bookingStatus           BookingStatus?
  plannedPlaceOfDelivery  String?

  // --- Previous Pregnancy Complications ---
  previousPreeclampsia    Boolean?
  previousEclampsia       Boolean?
  gestationalHypertension Boolean?
  chronicHypertensionBeforePregnancy Boolean?
  previousGestationalDiabetes Boolean?
  previousPostpartumHemorrhage Boolean?
  previousPretermBirth    Boolean?
  previousLowBirthWeight  Boolean?
  previousPlacentalAbruption Boolean?
  previousPlacentaPrevia  Boolean?
  previousIufd            Boolean? // Intrauterine Fetal Death

  // --- Medical History ---
  chronicHypertension     Boolean?
  diabetesMellitus        Boolean?
  kidneyDisease           Boolean?
  heartDisease            Boolean?
  asthma                  Boolean?
  sickleCellDisease       Boolean?
  epilepsy                Boolean?
  thyroidDisease          Boolean?
  hivStatus               Boolean?
  hepatitisBStatus        Boolean?

  // --- Family History ---
  familyHypertension      Boolean?
  familyPreeclampsia      Boolean?
  familyDiabetes          Boolean?
  familyKidneyDisease     Boolean?
  familyMultiplePregnancy Boolean?

  // --- Lifestyle & Social History ---
  smokingStatus           SmokingStatus?
  alcoholUse              AlcoholUse?
  substanceUse            SubstanceUse?
  occupation              String?
  educationLevel          EducationLevel?
  distanceToFacility      Float?    // in km
  emergencyTransport      Boolean?
  supportPersonAvailable  Boolean?

  // Current Pregnancy Risk Factors
  bmi                     Float?

  // Risk History
  riskHistory             RiskHistory[]

  @@index([userId])
  @@index([facilityId])
  @@index([patientId])
  @@index([isActive])
  @@index([status])
  @@map("patient")
}

/**
 * Alert Entity
 */
model Alert {
  id         String    @id @default(uuid())
  facilityId String
  patientId  String
  type       String
  message    String
  isResolved Boolean   @default(false)
  resolvedAt DateTime?
  createdAt  DateTime  @default(now())
  updatedAt  DateTime  @updatedAt

  facility Facility @relation(fields: [facilityId], references: [id], onDelete: Cascade)
  patient  Patient  @relation(fields: [patientId], references: [id], onDelete: Cascade)

  @@index([facilityId])
  @@index([patientId])
  @@index([isResolved])
  @@map("alert")
}

/**
 * Referral Entity
 */

enum ReferralStatus {
  PENDING
  ACCEPTED
  COMPLETED
  CANCELLED
}

model Referral {
  id String @id @default(uuid())

  patientId String

  fromFacilityId String
  toFacilityId   String?

  reason String
  notes  String?

  status ReferralStatus @default(PENDING)

  referredAt  DateTime  @default(now())
  acceptedAt  DateTime?
  completedAt DateTime?

  patient Patient @relation(fields: [patientId], references: [id])

  fromFacility Facility @relation("OutgoingReferrals", fields: [fromFacilityId], references: [id])

  toFacility Facility? @relation("IncomingReferrals", fields: [toFacilityId], references: [id])

  createdAt  DateTime  @default(now())
  updatedAt  DateTime  @updatedAt
  facility   Facility? @relation(fields: [facilityId], references: [id])
  facilityId String?

  @@index([patientId])
  @@index([fromFacilityId])
  @@index([toFacilityId])
  @@index([status])
}

/**
 * User Status Enum
 */
enum UserStatus {
  PENDING
  ACTIVE
  SUSPENDED
}

/**
 * UserAuth Entity
 * CLINICAL SAFETY CONSTRAINTS:
 * - Minimal PII only (email OR phone, not both required)
 * - No health data in this table
 * - No logging of credentials
 * - Passwords are hashed (never stored in plain text)
 * DATA MINIMIZATION:
 * - Only authentication-related fields
 * - No names, addresses, or demographic data
 * - Health data stored in separate UserProfile table
 */
model UserAuth {
  id                   String    @id @default(uuid())
  email                String?   @unique
  phone                String?   @unique
  passwordHash         String? // bcrypt hashed password (null until setup)
  role                 UserRole  @default(PATIENT)
  status               UserStatus @default(PENDING)
  refreshToken         String? // For JWT refresh token rotation
  pushToken            String? // For Expo push notifications
  passwordSetupToken   String? // For initial password setup
  passwordSetupExpiresAt DateTime?
  passwordResetToken   String? // For forgot password
  passwordResetExpiresAt DateTime?
  isActive             Boolean   @default(true)
  createdAt            DateTime  @default(now())
  updatedAt            DateTime  @updatedAt

  // Relation to UserProfile (optional - created after registration)
  profile UserProfile?

  // Relation to BloodPressureReadings
  bloodPressureReadings BloodPressureReading[]

  // Relation to SymptomRecords
  symptomRecords SymptomRecord[]

  // Relation to Notifications
  notifications Notification[]

  // Relation to MonitoringStateRecord
  monitoringStateRecord MonitoringStateRecord?

  // Relation to FollowUpTasks
  followUpTasks FollowUpTask[]

  // Relation to Appointments
  appointments Appointment[]

  // Relation to HealthcareWorker
  healthcareWorker HealthcareWorker?

  // Relation to Patient
  patient Patient?

  @@index([email])
  @@index([phone])
  @@index([role])
  @@map("user_auth")
}

/**
 * Age Range Enum
 * DATA MINIMIZATION:
 * - Use age ranges instead of exact DOB
 * - Prevents unnecessary PII collection
 */
enum AgeRange {
  UNDER_18
  AGE_18_34
  AGE_35_PLUS
}

/**
 * Emergency Contact Relationship Enum
 * DATA MINIMIZATION:
 * - Relationship type only (no names stored)
 * - Supports midwife or closest relative
 */
enum EmergencyContactRelationship {
  MIDWIFE
  PARTNER
  FAMILY_MEMBER
  OTHER
}

/**
 * Known Conditions Enum
 * CLINICAL SAFETY:
 * - Enumerated list prevents free-text medical history
 * - Only high-risk pregnancy conditions relevant to hypertension
 * - No diagnostic information stored
 */
enum KnownCondition {
  CHRONIC_HYPERTENSION
  GESTATIONAL_DIABETES
  PREECLAMPSIA_HISTORY
  KIDNEY_DISEASE
  AUTOIMMUNE_DISORDER
  MULTIPLE_PREGNANCY
  NONE
}

/**
 * UserProfile Entity
 * DATA MINIMIZATION PRINCIPLES:
 * - No DOB (age range only)
 * - No address
 * - No free-text medical history
 * - No name or demographic data
 * - Only pregnancy-relevant information
 * CLINICAL SAFETY:
 * - All fields are enumerated or structured
 * - No diagnostic interpretations stored
 * - Links to UserAuth via userId
 */
model UserProfile {
  id                           String                        @id @default(uuid())
  userId                       String                        @unique
  ageRange                     AgeRange
  pregnancyWeeks               Int // Current week of pregnancy (0-42)
  firstPregnancy               Boolean
  knownConditions              KnownCondition[] // Array of enumerated conditions
  emergencyContactPhone        String? // Phone number only (no name)
  emergencyContactEmail        String? // Email address for emergency alerts
  emergencyContactRelationship EmergencyContactRelationship? // Relationship enum (e.g. MIDWIFE, PARTNER)

  // Clinic Information
  clinicName    String?
  clinicAddress String?
  clinicPhone   String?

  // Notification Preferences
  notifyCarePriority Boolean @default(true)
  notifyBpAlert      Boolean @default(true)
  notifySymptomAlert Boolean @default(true)
  notifyReminders    Boolean @default(true)
  reminderTime       String? @default("09:00") // 24h format (HH:mm)

  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt

  // Relation to UserAuth
  userAuth UserAuth @relation(fields: [userId], references: [id], onDelete: Cascade)

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

/**
 * Blood Pressure Reading Entity
 * CLINICAL SAFETY CONSTRAINTS:
 * - Manual entry only (no device integration)
 * - Do NOT label readings as normal/abnormal
 * - Do NOT store interpretations
 * - Neutral data handling only
 * VALIDATION:
 * - Systolic: 60-260 mmHg (physiologically possible range)
 * - Diastolic: 40-160 mmHg (physiologically possible range)
 * - Timestamp for temporal tracking
 * PURPOSE:
 * - Store raw BP measurements
 * - Used by care priority engine (Phase 3)
 * - No diagnostic labels attached to data
 */
model BloodPressureReading {
  id         String   @id @default(uuid())
  userId     String
  systolic   Int // mmHg (60-260)
  diastolic  Int // mmHg (40-160)
  recordedAt DateTime @default(now())
  createdAt  DateTime @default(now())

  // Relation to UserAuth
  userAuth UserAuth @relation(fields: [userId], references: [id], onDelete: Cascade)

  @@index([userId])
  @@index([recordedAt])
  @@map("blood_pressure_reading")
}

/**
 * Symptom Type Enum
 * CLINICAL SAFETY:
 * - Enumerated list of pregnancy hypertension warning signs
 * - Free-text is only allowed with OTHER for user-entered symptoms
 * - No severity levels
 * - Based on clinical guidelines for preeclampsia/eclampsia
 */
enum SymptomType {
  HEADACHE // Severe or persistent headache
  BLURRED_VISION // Visual disturbances
  SWELLING // Edema (face, hands, feet)
  VAGINAL_BLEEDING // Vaginal bleeding
  FEVER // Fever
  REDUCED_FETAL_MOVEMENT // Reduced fetal movement
  DIFFICULTY_BREATHING // Difficulty breathing
  CONVULSIONS // Convulsions
  UPPER_ABDOMINAL_PAIN // Right upper quadrant pain
  REDUCED_URINE // Decreased urine output
  NAUSEA_VOMITING // Persistent nausea/vomiting
  SHORTNESS_OF_BREATH // Difficulty breathing
  OTHER // User-entered symptom text stored separately
}

/**
 * Symptom Record Entity
 * CLINICAL SAFETY CONSTRAINTS:
 * - Atomic recording (one symptom per record)
 * - No severity levels
 * - No numeric scoring
 * - No interpretation or diagnosis
 * PURPOSE:
 * - Track presence of warning symptoms
 * - Used by care priority engine for escalation
 * - Each symptom is a separate, timestamped record
 */
model SymptomRecord {
  id            String      @id @default(uuid())
  userId        String
  symptomType   SymptomType
  customSymptom String?
  recordedAt    DateTime    @default(now())
  createdAt     DateTime    @default(now())

  // Relation to UserAuth
  userAuth UserAuth @relation(fields: [userId], references: [id], onDelete: Cascade)

  @@index([userId])
  @@index([recordedAt])
  @@index([symptomType])
  @@map("symptom_record")
}

/**
 * Notification Type Enum
 */
enum NotificationType {
  CARE_PRIORITY
  BP_ALERT
  SYMPTOM_ALERT
  REMINDER
  EDUCATIONAL
}

/**
 * Notification Priority Enum
 */
enum NotificationPriority {
  INFORMATIONAL
  EDUCATIONAL
  REMINDER
  ELEVATED_RISK
  CRITICAL
}

/**
 * Notification Category Enum
 */
enum NotificationCategory {
  PREECLAMPSIA_AWARENESS
  BP_MONITORING
  PREGNANCY_WARNING_SIGNS
  HYDRATION
  REST
  ANTENATAL_CARE
  SYMPTOM_AWARENESS
  TRIMESTER_GUIDANCE
}

/**
 * Notification Entity
 * PURPOSE:
 * - Store history of alerts and notifications
 * - Track read status
 */
model Notification {
  id        String                @id @default(uuid())
  userId    String
  type      NotificationType
  priority  NotificationPriority  @default(REMINDER)
  category  NotificationCategory?
  title     String
  message   String
  read      Boolean               @default(false)
  createdAt DateTime              @default(now())

  userAuth UserAuth @relation(fields: [userId], references: [id], onDelete: Cascade)

  @@index([userId])
  @@index([createdAt])
  @@map("notification")
}

/**
 * MonitoringState Enum
 * Defines the possible states of the monitoring system for a user.
 */
enum MonitoringState {
  NORMAL
  MONITOR
  URGENT
  EMERGENCY
}

/**
 * MonitoringStateRecord Entity
 * Stores the current monitoring state for each user.
 */
model MonitoringStateRecord {
  id            String          @id @default(uuid())
  userId        String          @unique
  currentState  MonitoringState
  lastUpdatedAt DateTime        @default(now())
  reason        String?

  userAuth UserAuth @relation(fields: [userId], references: [id], onDelete: Cascade)

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

/**
 * FollowUpTaskType Enum
 * Defines the types of follow-up tasks.
 */
enum FollowUpTaskType {
  RECHECK
  SEEK_CARE
}

/**
 * FollowUpTaskStatus Enum
 * Defines the status of follow-up tasks.
 */
enum FollowUpTaskStatus {
  PENDING
  COMPLETED
  MISSED
}

enum PatientStatus {
  ACTIVE
  DEFAULTER
  DELIVERED
  TRANSFERRED
  LOST_TO_FOLLOW_UP
}

/**
 * FollowUpTask Entity
 * Stores details about each follow-up task.
 */
model FollowUpTask {
  id               String             @id @default(uuid())
  userId           String
  type             FollowUpTaskType
  dueAt            DateTime
  status           FollowUpTaskStatus @default(PENDING)
  relatedReadingId String? // Optional: Link to a specific BP reading that triggered the task

  userAuth UserAuth @relation(fields: [userId], references: [id], onDelete: Cascade)

  @@index([userId])
  @@index([dueAt])
  @@index([status])
  @@map("follow_up_task")
}

enum AppointmentType {
  ANC
  LAB
  SCAN
}

enum AppointmentStatus {
  SCHEDULED
  COMPLETED
  MISSED
}

enum UrineProtein {
  NEGATIVE
  TRACE
  PLUS_1
  PLUS_2
  PLUS_3
}

enum RiskLevel {
  LOW
  MODERATE
  HIGH
  EMERGENCY
}

model Appointment {
  id         String            @id @default(uuid())
  userId     String
  facilityId String?
  patientId  String?
  type       AppointmentType
  title      String
  dateTime   DateTime
  location   String?
  notes      String?
  status     AppointmentStatus @default(SCHEDULED)
  createdAt  DateTime          @default(now())
  updatedAt  DateTime          @updatedAt

  userAuth UserAuth  @relation(fields: [userId], references: [id], onDelete: Cascade)
  facility Facility? @relation(fields: [facilityId], references: [id], onDelete: Cascade)
  patient  Patient?  @relation(fields: [patientId], references: [id], onDelete: Cascade)

  @@index([userId])
  @@index([facilityId])
  @@index([patientId])
  @@index([dateTime])
  @@map("appointment")
}

model ANCVisit {
  id String @id @default(uuid())

  patientId String
  patient   Patient @relation(fields: [patientId], references: [id], onDelete: Cascade)

  facilityId String
  facility   Facility @relation(fields: [facilityId], references: [id], onDelete: Cascade)

  healthcareWorkerId String
  healthcareWorker   HealthcareWorker @relation(fields: [healthcareWorkerId], references: [id], onDelete: Cascade)

  visitDate DateTime @default(now())

  gestationalAge Int?

  weight Float?

  bloodPressureSystolic  Int?
  bloodPressureDiastolic Int?

  urineProtein UrineProtein?

  fundalHeight Float?

  fetalHeartRate Int?

  fetalMovement Boolean?

  haemoglobin Float?

  temperature Float?

  remarks String?

  nextAppointmentDate DateTime?

  riskLevel RiskLevel @default(LOW)

  createdAt DateTime @default(now())

  updatedAt DateTime @updatedAt

  @@index([patientId])
  @@index([facilityId])
  @@index([healthcareWorkerId])
  @@index([visitDate])
  @@index([nextAppointmentDate])
  @@index([riskLevel])
  @@map("anc_visit")
}

model RiskHistory {
  id                    String    @id @default(uuid())
  patientId             String
  patient               Patient   @relation(fields: [patientId], references: [id], onDelete: Cascade)
  riskLevel             RiskLevel
  score                 Int
  reasons               String[]
  contributingFactorIds String[]
  recommendations       String[]
  isRedFlag             Boolean
  redFlagReasons        String[]
  calculatedAt          DateTime  @default(now())
  recordedBy            String?
  createdAt             DateTime  @default(now())
  updatedAt             DateTime  @updatedAt

  @@index([patientId])
  @@index([calculatedAt])
  @@map("risk_history")
}