Dragon-Knight/internal/towns/towns.go

package towns

import (
	"fmt"
	"strings"

	"dk/internal/database"

	"zombiezen.com/go/sqlite"
)

// Town represents a town in the database
type Town struct {
	ID       int    `json:"id"`
	Name     string `json:"name"`
	X        int    `json:"x"`
	Y        int    `json:"y"`
	InnCost  int    `json:"inn_cost"`
	MapCost  int    `json:"map_cost"`
	TPCost   int    `json:"tp_cost"`
	ShopList string `json:"shop_list"`
}

// Find retrieves a town by ID
func Find(id int) (*Town, error) {
	town := &Town{}

	query := "SELECT id, name, x, y, inn_cost, map_cost, tp_cost, shop_list FROM towns WHERE id = ?"
	err := database.Query(query, func(stmt *sqlite.Stmt) error {
		town.ID = stmt.ColumnInt(0)
		town.Name = stmt.ColumnText(1)
		town.X = stmt.ColumnInt(2)
		town.Y = stmt.ColumnInt(3)
		town.InnCost = stmt.ColumnInt(4)
		town.MapCost = stmt.ColumnInt(5)
		town.TPCost = stmt.ColumnInt(6)
		town.ShopList = stmt.ColumnText(7)
		return nil
	}, id)

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

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

	return town, nil
}

// All retrieves all towns
func All() ([]*Town, error) {
	var towns []*Town

	query := "SELECT id, name, x, y, inn_cost, map_cost, tp_cost, shop_list FROM towns ORDER BY id"
	err := database.Query(query, func(stmt *sqlite.Stmt) error {
		town := &Town{
			ID:       stmt.ColumnInt(0),
			Name:     stmt.ColumnText(1),
			X:        stmt.ColumnInt(2),
			Y:        stmt.ColumnInt(3),
			InnCost:  stmt.ColumnInt(4),
			MapCost:  stmt.ColumnInt(5),
			TPCost:   stmt.ColumnInt(6),
			ShopList: stmt.ColumnText(7),
		}
		towns = append(towns, town)
		return nil
	})

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

	return towns, nil
}

// ByName retrieves a town by name (case-insensitive)
func ByName(name string) (*Town, error) {
	town := &Town{}

	query := "SELECT id, name, x, y, inn_cost, map_cost, tp_cost, shop_list FROM towns WHERE LOWER(name) = LOWER(?) LIMIT 1"
	err := database.Query(query, func(stmt *sqlite.Stmt) error {
		town.ID = stmt.ColumnInt(0)
		town.Name = stmt.ColumnText(1)
		town.X = stmt.ColumnInt(2)
		town.Y = stmt.ColumnInt(3)
		town.InnCost = stmt.ColumnInt(4)
		town.MapCost = stmt.ColumnInt(5)
		town.TPCost = stmt.ColumnInt(6)
		town.ShopList = stmt.ColumnText(7)
		return nil
	}, name)

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

	if town.ID == 0 {
		return nil, fmt.Errorf("town with name '%s' not found", name)
	}

	return town, nil
}

// ByMaxInnCost retrieves towns with inn cost at most the specified amount
func ByMaxInnCost(maxCost int) ([]*Town, error) {
	var towns []*Town

	query := "SELECT id, name, x, y, inn_cost, map_cost, tp_cost, shop_list FROM towns WHERE inn_cost <= ? ORDER BY inn_cost, id"
	err := database.Query(query, func(stmt *sqlite.Stmt) error {
		town := &Town{
			ID:       stmt.ColumnInt(0),
			Name:     stmt.ColumnText(1),
			X:        stmt.ColumnInt(2),
			Y:        stmt.ColumnInt(3),
			InnCost:  stmt.ColumnInt(4),
			MapCost:  stmt.ColumnInt(5),
			TPCost:   stmt.ColumnInt(6),
			ShopList: stmt.ColumnText(7),
		}
		towns = append(towns, town)
		return nil
	}, maxCost)

	if err != nil {
		return nil, fmt.Errorf("failed to retrieve towns by max inn cost: %w", err)
	}

	return towns, nil
}

// ByMaxTPCost retrieves towns with teleport cost at most the specified amount
func ByMaxTPCost(maxCost int) ([]*Town, error) {
	var towns []*Town

	query := "SELECT id, name, x, y, inn_cost, map_cost, tp_cost, shop_list FROM towns WHERE tp_cost <= ? ORDER BY tp_cost, id"
	err := database.Query(query, func(stmt *sqlite.Stmt) error {
		town := &Town{
			ID:       stmt.ColumnInt(0),
			Name:     stmt.ColumnText(1),
			X:        stmt.ColumnInt(2),
			Y:        stmt.ColumnInt(3),
			InnCost:  stmt.ColumnInt(4),
			MapCost:  stmt.ColumnInt(5),
			TPCost:   stmt.ColumnInt(6),
			ShopList: stmt.ColumnText(7),
		}
		towns = append(towns, town)
		return nil
	}, maxCost)

	if err != nil {
		return nil, fmt.Errorf("failed to retrieve towns by max TP cost: %w", err)
	}

	return towns, nil
}

// ByCoords retrieves a town by its x, y coordinates
func ByCoords(x, y int) (*Town, error) {
	town := &Town{}

	query := `SELECT id, name, x, y, inn_cost, map_cost, tp_cost, shop_list
			  FROM towns WHERE x = ? AND y = ? LIMIT 1`
	err := database.Query(query, func(stmt *sqlite.Stmt) error {
		town.ID = stmt.ColumnInt(0)
		town.Name = stmt.ColumnText(1)
		town.X = stmt.ColumnInt(2)
		town.Y = stmt.ColumnInt(3)
		town.InnCost = stmt.ColumnInt(4)
		town.MapCost = stmt.ColumnInt(5)
		town.TPCost = stmt.ColumnInt(6)
		town.ShopList = stmt.ColumnText(7)
		return nil
	}, x, y)

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

	return town, nil
}

// ByDistance retrieves towns within a certain distance from a point
func ByDistance(fromX, fromY, maxDistance int) ([]*Town, error) {
	var towns []*Town

	query := `SELECT id, name, x, y, inn_cost, map_cost, tp_cost, shop_list
			  FROM towns
			  WHERE ((x - ?) * (x - ?) + (y - ?) * (y - ?)) <= ?
			  ORDER BY ((x - ?) * (x - ?) + (y - ?) * (y - ?)), id`

	maxDistance2 := maxDistance * maxDistance
	err := database.Query(query, func(stmt *sqlite.Stmt) error {
		town := &Town{
			ID:       stmt.ColumnInt(0),
			Name:     stmt.ColumnText(1),
			X:        stmt.ColumnInt(2),
			Y:        stmt.ColumnInt(3),
			InnCost:  stmt.ColumnInt(4),
			MapCost:  stmt.ColumnInt(5),
			TPCost:   stmt.ColumnInt(6),
			ShopList: stmt.ColumnText(7),
		}
		towns = append(towns, town)
		return nil
	}, fromX, fromX, fromY, fromY, maxDistance2, fromX, fromX, fromY, fromY)

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

	return towns, nil
}

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

	query := `UPDATE towns SET name = ?, x = ?, y = ?, inn_cost = ?, map_cost = ?, tp_cost = ?, shop_list = ? WHERE id = ?`
	return database.Exec(query, t.Name, t.X, t.Y, t.InnCost, t.MapCost, t.TPCost, t.ShopList, t.ID)
}

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

	query := "DELETE FROM towns WHERE id = ?"
	return database.Exec(query, t.ID)
}

// GetShopItems returns the shop items as a slice of item IDs
func (t *Town) GetShopItems() []string {
	if t.ShopList == "" {
		return []string{}
	}
	return strings.Split(t.ShopList, ",")
}

// SetShopItems sets the shop items from a slice of item IDs
func (t *Town) SetShopItems(items []string) {
	t.ShopList = strings.Join(items, ",")
}

// HasShopItem checks if the town's shop sells a specific item ID
func (t *Town) HasShopItem(itemID string) bool {
	items := t.GetShopItems()
	for _, item := range items {
		if strings.TrimSpace(item) == itemID {
			return true
		}
	}
	return false
}

// DistanceFrom calculates the distance from this town to given coordinates
func (t *Town) DistanceFrom(x, y int) float64 {
	dx := float64(t.X - x)
	dy := float64(t.Y - y)
	return dx*dx + dy*dy // Return squared distance for performance
}

// IsStartingTown returns true if this is the starting town (Midworld)
func (t *Town) IsStartingTown() bool {
	return t.X == 0 && t.Y == 0
}

// CanAffordInn returns true if the player can afford the inn
func (t *Town) CanAffordInn(gold int) bool {
	return gold >= t.InnCost
}

// CanAffordMap returns true if the player can afford to buy the map
func (t *Town) CanAffordMap(gold int) bool {
	return gold >= t.MapCost
}

// CanAffordTeleport returns true if the player can afford to teleport here
func (t *Town) CanAffordTeleport(gold int) bool {
	return gold >= t.TPCost
}