package player

import (
	"fmt"
	"os"
	"path/filepath"
	"strings"

	"gopkg.in/yaml.v3"
	"thehouseoficarus/internal/item"
)

type AccountStore struct {
	dataDir string
}

func NewAccountStore(dataDir string) *AccountStore {
	return &AccountStore{dataDir: dataDir}
}

func (s *AccountStore) AccountPath(name string) string {
	return filepath.Join(s.dataDir, "players", "accounts", name+".yaml")
}

func (s *AccountStore) LoadAccount(name string) (*Account, error) {
	path := s.AccountPath(name)
	data, err := os.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("account not found: %s", name)
	}
	var acc Account
	if err := yaml.Unmarshal(data, &acc); err != nil {
		return nil, fmt.Errorf("parse account: %w", err)
	}
	return &acc, nil
}

func (s *AccountStore) SaveAccount(acc *Account) error {
	path := s.AccountPath(acc.Name)
	data, err := yaml.Marshal(acc)
	if err != nil {
		return err
	}
	return os.WriteFile(path, data, 0644)
}

func (s *AccountStore) AccountExists(name string) bool {
	_, err := s.FindAccount(name)
	return err == nil
}

func (s *AccountStore) FindAccount(name string) (string, error) {
	path := s.AccountPath(name)
	if _, err := os.Stat(path); err == nil {
		return name, nil
	}
	dir := filepath.Join(s.dataDir, "players", "accounts")
	entries, err := os.ReadDir(dir)
	if err != nil {
		return "", fmt.Errorf("account not found: %s", name)
	}
	lower := strings.ToLower(name)
	for _, e := range entries {
		if e.IsDir() {
			continue
		}
		base := strings.TrimSuffix(e.Name(), ".yaml")
		if strings.ToLower(base) == lower {
			return base, nil
		}
	}
	return "", fmt.Errorf("account not found: %s", name)
}

func (s *AccountStore) CharPath(name string) string {
	return filepath.Join(s.dataDir, "players", "characters", name+".yaml")
}

func (s *AccountStore) LoadCharacter(name string) (*Player, error) {
	path := s.CharPath(name)
	data, err := os.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("character not found: %s", name)
	}
	var p Player
	if err := yaml.Unmarshal(data, &p); err != nil {
		return nil, fmt.Errorf("parse character: %w", err)
	}
	if p.Skills == nil {
		p.Skills = make(map[SkillName]int)
	}
	if p.Equipment == nil {
		p.Equipment = make(map[item.EquipSlot]string)
	}
	if p.Inventory == nil {
		p.Inventory = make(map[int]*InventorySlot)
	}
	if p.MapSymbols == nil {
		p.MapSymbols = make(map[int]MapSymbolData)
	}
	return &p, nil
}

func (s *AccountStore) SaveCharacter(p *Player) error {
	path := s.CharPath(p.Name)
	if p.GodMode && p.GodBackup != nil {
		buffedSkills := p.Skills
		buffedHP := p.HP
		p.Skills = p.GodBackup
		if p.HP > p.MaxHP() {
			p.HP = p.MaxHP()
		}
		defer func() {
			p.Skills = buffedSkills
			p.HP = buffedHP
		}()
	}
	data, err := yaml.Marshal(p)
	if err != nil {
		return err
	}
	return os.WriteFile(path, data, 0644)
}

func (s *AccountStore) CharacterExists(name string) bool {
	_, err := s.FindCharacter(name)
	return err == nil
}

func (s *AccountStore) FindCharacter(name string) (string, error) {
	path := s.CharPath(name)
	if _, err := os.Stat(path); err == nil {
		return name, nil
	}
	dir := filepath.Join(s.dataDir, "players", "characters")
	entries, err := os.ReadDir(dir)
	if err != nil {
		return "", fmt.Errorf("character not found: %s", name)
	}
	lower := strings.ToLower(name)
	for _, e := range entries {
		if e.IsDir() {
			continue
		}
		base := strings.TrimSuffix(e.Name(), ".yaml")
		if strings.ToLower(base) == lower {
			return base, nil
		}
	}
	return "", fmt.Errorf("character not found: %s", name)
}

// ListCharacterNames returns the stem (character name) of every
// data/players/characters/*.yaml file. Used by room-ID migration to walk and
// rewrite offline characters. Online characters are excluded by the caller
// (their in-memory state is updated directly).
func (s *AccountStore) ListAccountNames() ([]string, error) {
	dir := filepath.Join(s.dataDir, "players", "accounts")
	entries, err := os.ReadDir(dir)
	if err != nil {
		return nil, err
	}
	var names []string
	for _, e := range entries {
		if e.IsDir() {
			continue
		}
		name := strings.TrimSuffix(e.Name(), ".yaml")
		if name == "" {
			continue
		}
		names = append(names, name)
	}
	return names, nil
}

func (s *AccountStore) ListCharacterNames() ([]string, error) {
	dir := filepath.Join(s.dataDir, "players", "characters")
	entries, err := os.ReadDir(dir)
	if err != nil {
		return nil, err
	}
	var names []string
	for _, e := range entries {
		if e.IsDir() {
			continue
		}
		name := strings.TrimSuffix(e.Name(), ".yaml")
		if name == "" {
			continue
		}
		names = append(names, name)
	}
	return names, nil
}