package savegame import ( "bufio" "crypto/sha1" "encoding/hex" "encoding/json" "errors" "fmt" "os" "path/filepath" "strings" "time" "git.kirsle.net/apps/doodle/pkg/usercfg" "git.kirsle.net/apps/doodle/pkg/userdir" ) // SaveGame holds the user's progress thru level packs. type SaveGame struct { LevelPacks map[string]*LevelPack `json:"levelPacks"` } // LevelPack holds savegame process for a level pack. type LevelPack struct { Levels map[string]*Level `json:"levels"` } // Level holds high score information for a level. type Level struct { Completed bool `json:"completed"` BestTime *time.Duration `json:"bestTime"` PerfectTime *time.Duration `json:"perfectTime"` } // New creates a new SaveGame. func New() *SaveGame { return &SaveGame{ LevelPacks: map[string]*LevelPack{}, } } // NewLevelPack initializes a LevelPack struct. func NewLevelPack() *LevelPack { return &LevelPack{ Levels: map[string]*Level{}, } } // GetOrCreate the save game JSON. If the save file isn't found OR has an // invalid checksum, it is created. Always returns a valid SaveGame struct // and the error may communicate if there was a problem reading an existing file. func GetOrCreate() (*SaveGame, error) { if sg, err := Load(); err == nil { return sg, nil } else { return New(), err } } // Load the save game JSON from the user's profile directory. func Load() (*SaveGame, error) { fh, err := os.Open(userdir.SaveFile) if err != nil { return nil, err } // Read the checksum line. scanner := bufio.NewScanner(fh) scanner.Scan() var ( checksum = scanner.Text() jsontext []byte ) for scanner.Scan() { jsontext = append(jsontext, scanner.Bytes()...) } // Validate the checksum. if !verifyChecksum(jsontext, checksum) { return nil, errors.New("checksum error") } // Parse the JSON. var sg = New() err = json.Unmarshal(jsontext, sg) if err != nil { return nil, err } return sg, nil } // Save the savegame.json to disk. func (sg *SaveGame) Save() error { // Encode to JSON. text, err := json.Marshal(sg) if err != nil { return err } // Create the checksum. checksum := makeChecksum(text) // Write the file. fh, err := os.Create(userdir.SaveFile) if err != nil { return err } defer fh.Close() fh.Write([]byte(checksum)) fh.Write([]byte{'\n'}) fh.Write(text) return nil } // MarkCompleted is a helper function to mark a levelpack level completed. // Parameters are the filename of the levelpack and the level therein. // Extra path info except the base filename is stripped from both. func (sg *SaveGame) MarkCompleted(levelpack, filename string) { lvl := sg.GetLevelScore(levelpack, filename) lvl.Completed = true } // NewHighScore may set a new highscore for a level. // // The level will be marked Completed and if the given score is better // than the stored one it will update. // // Returns true if a new high score was logged. func (sg *SaveGame) NewHighScore(levelpack, filename string, isPerfect bool, elapsed time.Duration) bool { levelpack = filepath.Base(levelpack) filename = filepath.Base(filename) score := sg.GetLevelScore(levelpack, filename) score.Completed = true var newHigh bool if isPerfect { if score.PerfectTime == nil || *score.PerfectTime > elapsed { score.PerfectTime = &elapsed newHigh = true } } else { if score.BestTime == nil || *score.BestTime > elapsed { score.BestTime = &elapsed newHigh = true } } if newHigh { if sg.LevelPacks[levelpack] == nil { sg.LevelPacks[levelpack] = NewLevelPack() } sg.LevelPacks[levelpack].Levels[filename] = score } return newHigh } // GetLevelScore finds or creates a default Level score. func (sg *SaveGame) GetLevelScore(levelpack, filename string) *Level { levelpack = filepath.Base(levelpack) filename = filepath.Base(filename) if _, ok := sg.LevelPacks[levelpack]; !ok { sg.LevelPacks[levelpack] = NewLevelPack() } if row, ok := sg.LevelPacks[levelpack].Levels[filename]; ok { return row } else { row = &Level{} sg.LevelPacks[levelpack].Levels[filename] = row return row } } // CountCompleted returns the number of completed levels in a levelpack. func (sg *SaveGame) CountCompleted(levelpack string) int { var count int levelpack = filepath.Base(levelpack) if lp, ok := sg.LevelPacks[levelpack]; ok { for _, lvl := range lp.Levels { if lvl.Completed { count++ } } } return count } // FormatDuration pretty prints a time.Duration in MM:SS format. func FormatDuration(d time.Duration) string { var ( millisecond = d.Milliseconds() second = (millisecond / 1000) % 60 minute = (millisecond / (1000 * 60)) % 60 hour = (millisecond / (1000 * 60 * 60)) % 24 ms = fmt.Sprintf("%d", millisecond%1000) ) // Limit milliseconds to 2 digits. if len(ms) > 2 { ms = ms[:2] } return strings.TrimPrefix( fmt.Sprintf("%02d:%02d:%02d.%s", hour, minute, second, ms), "00:", ) } // Hashing key that goes into the level's save data. var secretKey = []byte(`Sc\x96R\x8e\xba\x96\x8e\x1fg\x01Q\xf5\xcbIX`) func makeChecksum(jsontext []byte) string { h := sha1.New() h.Write(jsontext) h.Write(secretKey) h.Write(usercfg.Current.Entropy) return hex.EncodeToString(h.Sum(nil)) } func verifyChecksum(jsontext []byte, checksum string) bool { expect := makeChecksum(jsontext) return expect == checksum }