Dragon-Knight/internal/users/doc.go

/*
Package users is the active record implementation for user accounts in the game.

The users package provides comprehensive user management for the game, including authentication, character progression, inventory, equipment, and game state management. It handles all aspects of player accounts from registration to advanced gameplay features.

# Basic Usage

To retrieve a user by ID:

	user, err := users.Find(db, 1)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("User: %s (Level %d)\n", user.Username, user.Level)

To find a user by username:

	user, err := users.ByUsername(db, "playerName")
	if err != nil {
		log.Fatal(err)
	}

To find a user by email:

	user, err := users.ByEmail(db, "player@example.com")
	if err != nil {
		log.Fatal(err)
	}

# Creating Users with Builder Pattern

The package provides a comprehensive builder for creating new user accounts:

## Basic User Creation

	user, err := users.NewBuilder(db).
		WithUsername("newplayer").
		WithPassword("hashedPassword").
		WithEmail("newplayer@example.com").
		WithClassID(1).
		Create()

	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("Created user with ID: %d\n", user.ID)

## Advanced User Creation

	user, err := users.NewBuilder(db).
		WithUsername("hero").
		WithPassword("secureHash").
		WithEmail("hero@example.com").
		WithVerified(true).
		WithClassID(2).
		WithPosition(100, -50).
		WithLevel(5).
		WithGold(500).
		WithStats(8, 7, 10, 9). // strength, dex, attack, defense
		WithHP(30, 30).
		WithMP(20, 20).
		WithSpells([]string{"1", "3", "5"}).
		WithTowns([]string{"1", "2"}).
		AsAdmin().
		Create()

The builder automatically sets sensible defaults for all fields if not specified.

# User Management

## Authentication and Verification

	user, _ := users.Find(db, userID)
	
	// Check verification status
	if user.IsVerified() {
		fmt.Println("User email is verified")
	}
	
	// Check authorization levels
	if user.IsAdmin() {
		fmt.Println("User has admin privileges")
	}
	if user.IsModerator() {
		fmt.Println("User has moderator privileges")
	}

## Activity Tracking

	// Update last online time
	user.UpdateLastOnline()
	user.Save()
	
	// Get activity information
	registered := user.RegisteredTime()
	lastOnline := user.LastOnlineTime()
	
	fmt.Printf("Registered: %s\n", registered.Format("Jan 2, 2006"))
	fmt.Printf("Last online: %s\n", lastOnline.Format("Jan 2 15:04"))

# Character Management

## Stats and Progression

	user, _ := users.Find(db, userID)
	
	// Get character stats
	stats := user.GetStats()
	fmt.Printf("Level %d: HP %d/%d, MP %d/%d\n", 
		stats["level"], stats["hp"], stats["max_hp"], 
		stats["mp"], stats["max_mp"])
	
	// Update character progression
	user.Level = 10
	user.Exp = 5000
	user.MaxHP = 50
	user.HP = 50
	user.Save()

## Position and Movement

	// Get current position
	x, y := user.GetPosition()
	fmt.Printf("Player at (%d, %d)\n", x, y)
	
	// Move player
	user.SetPosition(newX, newY)
	user.Currently = "Exploring the forest"
	user.Save()

## Combat Status

	if user.IsFighting() {
		fmt.Printf("Fighting monster ID %d (HP: %d)\n", 
			user.MonsterID, user.MonsterHP)
	}
	
	if user.IsAlive() {
		fmt.Printf("Player has %d HP remaining\n", user.HP)
	}

# Spell System

## Spell Management

	user, _ := users.Find(db, userID)
	
	// Get known spells
	spells := user.GetSpellIDs()
	fmt.Printf("Player knows %d spells: %v\n", len(spells), spells)
	
	// Check if player knows a specific spell
	if user.HasSpell("5") {
		fmt.Println("Player knows spell 5")
	}
	
	// Learn new spells
	newSpells := append(spells, "7", "8")
	user.SetSpellIDs(newSpells)
	user.Save()

## Spell Integration

	func castSpell(db *database.DB, userID int, spellID string) error {
		user, err := users.Find(db, userID)
		if err != nil {
			return err
		}
		
		if !user.HasSpell(spellID) {
			return fmt.Errorf("user doesn't know spell %s", spellID)
		}
		
		// Spell casting logic here...
		return nil
	}

# Town and Travel System

## Town Visits

	user, _ := users.Find(db, userID)
	
	// Get visited towns
	towns := user.GetTownIDs()
	fmt.Printf("Visited %d towns: %v\n", len(towns), towns)
	
	// Check if player has visited a town
	if user.HasVisitedTown("3") {
		fmt.Println("Player has been to town 3")
	}
	
	// Visit new town
	visitedTowns := append(towns, "4")
	user.SetTownIDs(visitedTowns)
	user.Save()

## Travel Integration

	func visitTown(db *database.DB, userID int, townID string) error {
		user, err := users.Find(db, userID)
		if err != nil {
			return err
		}
		
		// Add town to visited list if not already there
		if !user.HasVisitedTown(townID) {
			towns := user.GetTownIDs()
			user.SetTownIDs(append(towns, townID))
		}
		
		// Update position and status
		// town coordinates would be looked up here
		user.Currently = fmt.Sprintf("In town %s", townID)
		return user.Save()
	}

# Equipment System

## Equipment Management

	user, _ := users.Find(db, userID)
	
	// Get all equipment
	equipment := user.GetEquipment()
	weapon := equipment["weapon"].(map[string]interface{})
	armor := equipment["armor"].(map[string]interface{})
	
	fmt.Printf("Weapon: %s (ID: %d)\n", weapon["name"], weapon["id"])
	fmt.Printf("Armor: %s (ID: %d)\n", armor["name"], armor["id"])
	
	// Equip new items
	user.WeaponID = 15
	user.WeaponName = "Dragon Sword"
	user.ArmorID = 8
	user.ArmorName = "Steel Plate"
	user.Save()

# Query Operations

## Level-Based Queries

	// Get all players at a specific level
	level5Players, err := users.ByLevel(db, 5)
	if err != nil {
		log.Fatal(err)
	}
	
	fmt.Printf("Level 5 players (%d):\n", len(level5Players))
	for _, player := range level5Players {
		fmt.Printf("- %s (EXP: %d)\n", player.Username, player.Exp)
	}

## Online Status Queries

	// Get players online in the last hour
	onlinePlayers, err := users.Online(db, time.Hour)
	if err != nil {
		log.Fatal(err)
	}
	
	fmt.Printf("Players online in last hour (%d):\n", len(onlinePlayers))
	for _, player := range onlinePlayers {
		lastSeen := time.Since(player.LastOnlineTime())
		fmt.Printf("- %s (last seen %v ago)\n", player.Username, lastSeen)
	}

# Database Schema

The users table contains extensive character and game state information:

	CREATE TABLE users (
		id             INTEGER PRIMARY KEY AUTOINCREMENT,
		username       TEXT NOT NULL,
		password       TEXT NOT NULL,
		email          TEXT NOT NULL,
		verified       INTEGER NOT NULL DEFAULT 0,
		token          TEXT NOT NULL DEFAULT '',
		registered     INTEGER NOT NULL DEFAULT (unixepoch()),
		last_online    INTEGER NOT NULL DEFAULT (unixepoch()),
		auth           INTEGER NOT NULL DEFAULT 0,
		x              INTEGER NOT NULL DEFAULT 0,
		y              INTEGER NOT NULL DEFAULT 0,
		class_id       INTEGER NOT NULL DEFAULT 0,
		currently      TEXT NOT NULL DEFAULT 'In Town',
		fighting       INTEGER NOT NULL DEFAULT 0,
		-- Combat state fields
		monster_id     INTEGER NOT NULL DEFAULT 0,
		monster_hp     INTEGER NOT NULL DEFAULT 0,
		monster_sleep  INTEGER NOT NULL DEFAULT 0,
		monster_immune INTEGER NOT NULL DEFAULT 0,
		uber_damage    INTEGER NOT NULL DEFAULT 0,
		uber_defense   INTEGER NOT NULL DEFAULT 0,
		-- Character stats
		hp             INTEGER NOT NULL DEFAULT 15,
		mp             INTEGER NOT NULL DEFAULT 0,
		tp             INTEGER NOT NULL DEFAULT 10,
		max_hp         INTEGER NOT NULL DEFAULT 15,
		max_mp         INTEGER NOT NULL DEFAULT 0,
		max_tp         INTEGER NOT NULL DEFAULT 10,
		level          INTEGER NOT NULL DEFAULT 1,
		gold           INTEGER NOT NULL DEFAULT 100,
		exp            INTEGER NOT NULL DEFAULT 0,
		gold_bonus     INTEGER NOT NULL DEFAULT 0,
		exp_bonus      INTEGER NOT NULL DEFAULT 0,
		strength       INTEGER NOT NULL DEFAULT 5,
		dexterity      INTEGER NOT NULL DEFAULT 5,
		attack         INTEGER NOT NULL DEFAULT 5,
		defense        INTEGER NOT NULL DEFAULT 5,
		-- Equipment
		weapon_id      INTEGER NOT NULL DEFAULT 0,
		armor_id       INTEGER NOT NULL DEFAULT 0,
		shield_id      INTEGER NOT NULL DEFAULT 0,
		slot_1_id      INTEGER NOT NULL DEFAULT 0,
		slot_2_id      INTEGER NOT NULL DEFAULT 0,
		slot_3_id      INTEGER NOT NULL DEFAULT 0,
		weapon_name    TEXT NOT NULL DEFAULT '',
		armor_name     TEXT NOT NULL DEFAULT '',
		shield_name    TEXT NOT NULL DEFAULT '',
		slot_1_name    TEXT NOT NULL DEFAULT '',
		slot_2_name    TEXT NOT NULL DEFAULT '',
		slot_3_name    TEXT NOT NULL DEFAULT '',
		-- Game state
		drop_code      INTEGER NOT NULL DEFAULT 0,
		spells         TEXT NOT NULL DEFAULT '',
		towns          TEXT NOT NULL DEFAULT ''
	)

# Advanced Features

## Character Progression

	func levelUpCharacter(user *users.User, newLevel int) {
		user.Level = newLevel
		
		// Increase base stats
		user.MaxHP += 5
		user.HP = user.MaxHP // Full heal on level up
		user.MaxMP += 2
		user.MP = user.MaxMP
		
		// Stat bonuses
		user.Strength++
		user.Attack++
		user.Defense++
		
		user.Save()
	}

## Combat Integration

	func startCombat(user *users.User, monsterID int) error {
		if user.IsFighting() {
			return fmt.Errorf("already in combat")
		}
		
		user.Fighting = 1
		user.MonsterID = monsterID
		// monster HP would be looked up from monsters table
		user.MonsterHP = 50
		user.Currently = "Fighting"
		
		return user.Save()
	}
	
	func endCombat(user *users.User, won bool) error {
		user.Fighting = 0
		user.MonsterID = 0
		user.MonsterHP = 0
		user.MonsterSleep = 0
		user.MonsterImmune = 0
		
		if won {
			user.Currently = "Victorious"
			// Award experience and gold
		} else {
			user.Currently = "Defeated"
			user.HP = 0 // Player defeated
		}
		
		return user.Save()
	}

## Administrative Functions

	func promoteUser(db *database.DB, username string, authLevel int) error {
		user, err := users.ByUsername(db, username)
		if err != nil {
			return err
		}
		
		user.Auth = authLevel
		return user.Save()
	}
	
	func getUsersByAuthLevel(db *database.DB, minAuth int) ([]*users.User, error) {
		allUsers, err := users.All(db)
		if err != nil {
			return nil, err
		}
		
		var authorizedUsers []*users.User
		for _, user := range allUsers {
			if user.Auth >= minAuth {
				authorizedUsers = append(authorizedUsers, user)
			}
		}
		
		return authorizedUsers, nil
	}

# Performance Considerations

The users table is large and frequently accessed. Consider:

## Efficient Queries

	// Use specific lookups when possible
	user, _ := users.ByUsername(db, username) // Uses index
	user, _ := users.ByEmail(db, email)       // Uses index
	
	// Limit results for admin interfaces
	onlineUsers, _ := users.Online(db, time.Hour) // Bounded by time
	levelUsers, _ := users.ByLevel(db, targetLevel) // Bounded by level

## Caching Strategies

	// Cache frequently accessed user data
	type UserCache struct {
		users map[int]*users.User
		mutex sync.RWMutex
	}
	
	func (c *UserCache) GetUser(db *database.DB, id int) (*users.User, error) {
		c.mutex.RLock()
		if user, ok := c.users[id]; ok {
			c.mutex.RUnlock()
			return user, nil
		}
		c.mutex.RUnlock()
		
		user, err := users.Find(db, id)
		if err != nil {
			return nil, err
		}
		
		c.mutex.Lock()
		c.users[id] = user
		c.mutex.Unlock()
		
		return user, nil
	}

# Integration Examples

## Session Management

	func authenticateUser(db *database.DB, username, password string) (*users.User, error) {
		user, err := users.ByUsername(db, username)
		if err != nil {
			return nil, fmt.Errorf("user not found")
		}
		
		if !user.IsVerified() {
			return nil, fmt.Errorf("email not verified")
		}
		
		// Verify password (implement password checking)
		if !verifyPassword(user.Password, password) {
			return nil, fmt.Errorf("invalid password")
		}
		
		// Update last online
		user.UpdateLastOnline()
		user.Save()
		
		return user, nil
	}

## Game State Management

	func saveGameState(user *users.User, gameData GameState) error {
		user.X = gameData.X
		user.Y = gameData.Y
		user.HP = gameData.HP
		user.MP = gameData.MP
		user.Currently = gameData.Status
		
		if gameData.InCombat {
			user.Fighting = 1
			user.MonsterID = gameData.MonsterID
			user.MonsterHP = gameData.MonsterHP
		}
		
		return user.Save()
	}

The users package provides comprehensive player account management with support for all game mechanics including character progression, combat, equipment, spells, and world exploration.
*/
package users