Dragon-Knight/internal/drops/drops.go

package drops

import (
	"fmt"

	"dk/internal/database"

	"zombiezen.com/go/sqlite"
)

// Drop represents a drop item in the database
type Drop struct {
	ID    int    `json:"id"`
	Name  string `json:"name"`
	Level int    `json:"level"`
	Type  int    `json:"type"`
	Att   string `json:"att"`

	db *database.DB
}

// DropType constants for drop types
const (
	TypeConsumable = 1
)

// Find retrieves a drop by ID
func Find(db *database.DB, id int) (*Drop, error) {
	drop := &Drop{db: db}

	query := "SELECT id, name, level, type, att FROM drops WHERE id = ?"
	err := db.Query(query, func(stmt *sqlite.Stmt) error {
		drop.ID = stmt.ColumnInt(0)
		drop.Name = stmt.ColumnText(1)
		drop.Level = stmt.ColumnInt(2)
		drop.Type = stmt.ColumnInt(3)
		drop.Att = stmt.ColumnText(4)
		return nil
	}, id)

	if err != nil {
		return nil, fmt.Errorf("failed to find drop: %w", err)
	}

	if drop.ID == 0 {
		return nil, fmt.Errorf("drop with ID %d not found", id)
	}

	return drop, nil
}

// All retrieves all drops
func All(db *database.DB) ([]*Drop, error) {
	var drops []*Drop

	query := "SELECT id, name, level, type, att FROM drops ORDER BY id"
	err := db.Query(query, func(stmt *sqlite.Stmt) error {
		drop := &Drop{
			ID:    stmt.ColumnInt(0),
			Name:  stmt.ColumnText(1),
			Level: stmt.ColumnInt(2),
			Type:  stmt.ColumnInt(3),
			Att:   stmt.ColumnText(4),
			db:    db,
		}
		drops = append(drops, drop)
		return nil
	})

	if err != nil {
		return nil, fmt.Errorf("failed to retrieve all drops: %w", err)
	}

	return drops, nil
}

// ByLevel retrieves drops by minimum level requirement
func ByLevel(db *database.DB, minLevel int) ([]*Drop, error) {
	var drops []*Drop

	query := "SELECT id, name, level, type, att FROM drops WHERE level <= ? ORDER BY level, id"
	err := db.Query(query, func(stmt *sqlite.Stmt) error {
		drop := &Drop{
			ID:    stmt.ColumnInt(0),
			Name:  stmt.ColumnText(1),
			Level: stmt.ColumnInt(2),
			Type:  stmt.ColumnInt(3),
			Att:   stmt.ColumnText(4),
			db:    db,
		}
		drops = append(drops, drop)
		return nil
	}, minLevel)

	if err != nil {
		return nil, fmt.Errorf("failed to retrieve drops by level: %w", err)
	}

	return drops, nil
}

// ByType retrieves drops by type
func ByType(db *database.DB, dropType int) ([]*Drop, error) {
	var drops []*Drop

	query := "SELECT id, name, level, type, att FROM drops WHERE type = ? ORDER BY level, id"
	err := db.Query(query, func(stmt *sqlite.Stmt) error {
		drop := &Drop{
			ID:    stmt.ColumnInt(0),
			Name:  stmt.ColumnText(1),
			Level: stmt.ColumnInt(2),
			Type:  stmt.ColumnInt(3),
			Att:   stmt.ColumnText(4),
			db:    db,
		}
		drops = append(drops, drop)
		return nil
	}, dropType)

	if err != nil {
		return nil, fmt.Errorf("failed to retrieve drops by type: %w", err)
	}

	return drops, nil
}

// Builder provides a fluent interface for creating drops
type Builder struct {
	drop *Drop
	db   *database.DB
}

// NewBuilder creates a new drop builder
func NewBuilder(db *database.DB) *Builder {
	return &Builder{
		drop: &Drop{db: db},
		db:   db,
	}
}

// WithName sets the drop name
func (b *Builder) WithName(name string) *Builder {
	b.drop.Name = name
	return b
}

// WithLevel sets the drop level requirement
func (b *Builder) WithLevel(level int) *Builder {
	b.drop.Level = level
	return b
}

// WithType sets the drop type
func (b *Builder) WithType(dropType int) *Builder {
	b.drop.Type = dropType
	return b
}

// WithAtt sets the attributes
func (b *Builder) WithAtt(att string) *Builder {
	b.drop.Att = att
	return b
}

// Create saves the drop to the database and returns it
func (b *Builder) Create() (*Drop, error) {
	// Use a transaction to ensure we can get the ID
	var drop *Drop
	err := b.db.Transaction(func(tx *database.Tx) error {
		query := `INSERT INTO drops (name, level, type, att) 
		          VALUES (?, ?, ?, ?)`

		if err := tx.Exec(query, b.drop.Name, b.drop.Level, b.drop.Type, b.drop.Att); err != nil {
			return fmt.Errorf("failed to insert drop: %w", err)
		}

		// Get the last inserted ID within the same transaction
		var lastID int
		err := tx.Query("SELECT last_insert_rowid()", func(stmt *sqlite.Stmt) error {
			lastID = stmt.ColumnInt(0)
			return nil
		})
		if err != nil {
			return fmt.Errorf("failed to get last insert ID: %w", err)
		}

		// Create the drop with the ID
		drop = &Drop{
			ID:    lastID,
			Name:  b.drop.Name,
			Level: b.drop.Level,
			Type:  b.drop.Type,
			Att:   b.drop.Att,
			db:    b.db,
		}

		return nil
	})

	if err != nil {
		return nil, fmt.Errorf("failed to create drop: %w", err)
	}

	return drop, nil
}

// Save updates an existing drop in the database
func (d *Drop) Save() error {
	if d.ID == 0 {
		return fmt.Errorf("cannot save drop without ID")
	}

	query := `UPDATE drops SET name = ?, level = ?, type = ?, att = ? WHERE id = ?`
	return d.db.Exec(query, d.Name, d.Level, d.Type, d.Att, d.ID)
}

// Delete removes the drop from the database
func (d *Drop) Delete() error {
	if d.ID == 0 {
		return fmt.Errorf("cannot delete drop without ID")
	}

	query := "DELETE FROM drops WHERE id = ?"
	return d.db.Exec(query, d.ID)
}

// IsConsumable returns true if the drop is a consumable item
func (d *Drop) IsConsumable() bool {
	return d.Type == TypeConsumable
}

// TypeName returns the string representation of the drop type
func (d *Drop) TypeName() string {
	switch d.Type {
	case TypeConsumable:
		return "Consumable"
	default:
		return "Unknown"
	}
}