package valueobjects

import (
	"fmt"

	"knowfoolery/backend/shared/types"
	"knowfoolery/backend/shared/errors"
)

// Attempt represents a single answer attempt within a game session
type Attempt struct {
	id            types.AttemptID
	questionID    types.QuestionID
	attemptNumber int // 1, 2, or 3
	playerAnswer  string
	result        *AttemptResult
	hintUsed      bool
	attemptedAt   types.Timestamp
}

// NewAttempt creates a new attempt
func NewAttempt(
	questionID types.QuestionID,
	attemptNumber int,
	playerAnswer string,
	result *AttemptResult,
	hintUsed bool,
) (*Attempt, error) {
	// Validate inputs
	if questionID.IsEmpty() {
		return nil, errors.ErrValidationFailed("questionID", "question ID cannot be empty")
	}
	
	if attemptNumber < 1 || attemptNumber > types.MaxAttemptsPerQuestion {
		return nil, errors.ErrValidationFailed("attemptNumber", 
			"attempt number must be between 1 and 3")
	}
	
	if result == nil {
		return nil, errors.ErrValidationFailed("result", "attempt result cannot be nil")
	}
	
	// Player answer can be empty for timeout attempts
	
	attempt := &Attempt{
		id:            types.NewAttemptID(),
		questionID:    questionID,
		attemptNumber: attemptNumber,
		playerAnswer:  playerAnswer,
		result:        result,
		hintUsed:      hintUsed,
		attemptedAt:   types.NewTimestamp(),
	}
	
	return attempt, nil
}

// NewAttemptWithID creates an attempt with a specific ID (for loading from persistence)
func NewAttemptWithID(
	id types.AttemptID,
	questionID types.QuestionID,
	attemptNumber int,
	playerAnswer string,
	result *AttemptResult,
	hintUsed bool,
	attemptedAt types.Timestamp,
) (*Attempt, error) {
	if id.IsEmpty() {
		return nil, errors.ErrValidationFailed("id", "attempt ID cannot be empty")
	}
	
	if questionID.IsEmpty() {
		return nil, errors.ErrValidationFailed("questionID", "question ID cannot be empty")
	}
	
	if attemptNumber < 1 || attemptNumber > types.MaxAttemptsPerQuestion {
		return nil, errors.ErrValidationFailed("attemptNumber", 
			"attempt number must be between 1 and 3")
	}
	
	if result == nil {
		return nil, errors.ErrValidationFailed("result", "attempt result cannot be nil")
	}
	
	return &Attempt{
		id:            id,
		questionID:    questionID,
		attemptNumber: attemptNumber,
		playerAnswer:  playerAnswer,
		result:        result,
		hintUsed:      hintUsed,
		attemptedAt:   attemptedAt,
	}, nil
}

// ID returns the attempt's unique identifier
func (a *Attempt) ID() types.AttemptID {
	return a.id
}

// QuestionID returns the ID of the question this attempt is for
func (a *Attempt) QuestionID() types.QuestionID {
	return a.questionID
}

// AttemptNumber returns the attempt number (1, 2, or 3)
func (a *Attempt) AttemptNumber() int {
	return a.attemptNumber
}

// PlayerAnswer returns the answer provided by the player
func (a *Attempt) PlayerAnswer() string {
	return a.playerAnswer
}

// Result returns the result of this attempt
func (a *Attempt) Result() *AttemptResult {
	return a.result
}

// HintUsed returns true if a hint was used for this attempt
func (a *Attempt) HintUsed() bool {
	return a.hintUsed
}

// AttemptedAt returns when the attempt was made
func (a *Attempt) AttemptedAt() types.Timestamp {
	return a.attemptedAt
}

// IsCorrect returns true if the attempt was correct
func (a *Attempt) IsCorrect() bool {
	return a.result.IsCorrect()
}

// IsIncorrect returns true if the attempt was incorrect
func (a *Attempt) IsIncorrect() bool {
	return a.result.IsIncorrect()
}

// IsTimeout returns true if the attempt timed out
func (a *Attempt) IsTimeout() bool {
	return a.result.IsTimeout()
}

// PointsAwarded returns the points awarded for this attempt
func (a *Attempt) PointsAwarded() int {
	return a.result.PointsAwarded()
}

// IsFirstAttempt returns true if this is the first attempt for the question
func (a *Attempt) IsFirstAttempt() bool {
	return a.attemptNumber == 1
}

// IsLastAttempt returns true if this is the final attempt for the question
func (a *Attempt) IsLastAttempt() bool {
	return a.attemptNumber == types.MaxAttemptsPerQuestion
}

// GetMatchType returns the type of match (exact, fuzzy, incorrect, timeout)
func (a *Attempt) GetMatchType() string {
	return a.result.GetMatchType()
}

// GetSimilarity returns the similarity score between player and correct answer
func (a *Attempt) GetSimilarity() float64 {
	return a.result.Similarity()
}

// Equals checks if two attempts are the same (based on ID)
func (a *Attempt) Equals(other *Attempt) bool {
	if other == nil {
		return false
	}
	return a.id == other.id
}

// String returns a string representation of the attempt
func (a *Attempt) String() string {
	return fmt.Sprintf("Attempt %d: %s", a.attemptNumber, a.result.GetResultDescription())
}

// AttemptSnapshot represents a read-only view of attempt data
type AttemptSnapshot struct {
	ID            types.AttemptID     `json:"id"`
	QuestionID    types.QuestionID    `json:"question_id"`
	AttemptNumber int                 `json:"attempt_number"`
	PlayerAnswer  string              `json:"player_answer"`
	IsCorrect     bool                `json:"is_correct"`
	IsTimeout     bool                `json:"is_timeout"`
	PointsAwarded int                 `json:"points_awarded"`
	HintUsed      bool                `json:"hint_used"`
	MatchType     string              `json:"match_type"`
	Similarity    float64             `json:"similarity"`
	TimeTaken     string              `json:"time_taken"`
	AttemptedAt   types.Timestamp     `json:"attempted_at"`
	Result        *AttemptResultSummary `json:"result"`
}

// ToSnapshot creates a snapshot of the current attempt state
func (a *Attempt) ToSnapshot() *AttemptSnapshot {
	return &AttemptSnapshot{
		ID:            a.id,
		QuestionID:    a.questionID,
		AttemptNumber: a.attemptNumber,
		PlayerAnswer:  a.playerAnswer,
		IsCorrect:     a.IsCorrect(),
		IsTimeout:     a.IsTimeout(),
		PointsAwarded: a.PointsAwarded(),
		HintUsed:      a.hintUsed,
		MatchType:     a.GetMatchType(),
		Similarity:    a.GetSimilarity(),
		TimeTaken:     a.result.GetTimeTakenFormatted(),
		AttemptedAt:   a.attemptedAt,
		Result:        a.result.ToSummary(),
	}
}

// Validate performs comprehensive validation on the attempt
func (a *Attempt) Validate() *types.ValidationResult {
	result := types.NewValidationResult()
	
	// Validate ID
	if a.id.IsEmpty() {
		result.AddError("attempt ID cannot be empty")
	}
	
	// Validate question ID
	if a.questionID.IsEmpty() {
		result.AddError("question ID cannot be empty")
	}
	
	// Validate attempt number
	if a.attemptNumber < 1 || a.attemptNumber > types.MaxAttemptsPerQuestion {
		result.AddErrorf("attempt number must be between 1 and %d", types.MaxAttemptsPerQuestion)
	}
	
	// Validate result
	if a.result == nil {
		result.AddError("attempt result cannot be nil")
	}
	
	// Validate timestamp
	if a.attemptedAt.IsZero() {
		result.AddError("attempted timestamp cannot be zero")
	}
	
	// Business rule validations
	if a.IsTimeout() && a.playerAnswer != "" {
		result.AddError("timeout attempts should have empty player answer")
	}
	
	if !a.IsTimeout() && a.playerAnswer == "" {
		result.AddError("non-timeout attempts must have player answer")
	}
	
	return result
}

// GetAge returns how long ago this attempt was made
func (a *Attempt) GetAge() types.Duration {
	now := types.NewTimestamp()
	age := now.Sub(a.attemptedAt)
	return types.NewDuration(age)
}

// Clone creates a deep copy of the attempt (for testing or other purposes)
func (a *Attempt) Clone() *Attempt {
	return &Attempt{
		id:            a.id,
		questionID:    a.questionID,
		attemptNumber: a.attemptNumber,
		playerAnswer:  a.playerAnswer,
		result:        a.result, // AttemptResult is immutable
		hintUsed:      a.hintUsed,
		attemptedAt:   a.attemptedAt,
	}
}