package ai

import (
	"database/sql/driver"
	"time"

	"rideaware/internal/workout"
)

// GenerateRequest is the user's request for AI workout generation
type GenerateRequest struct {
	PlanDuration   int      `json:"plan_duration"`    // Number of days (1, 7, 14, 28)
	FocusAreas     []string `json:"focus_areas"`      // ["endurance", "threshold", "vo2max", "recovery", "sprint", "sweet_spot"]
	IntensityLevel string   `json:"intensity_level"`  // "easy", "moderate", "hard"
	WeeklyHours    int      `json:"weekly_hours"`     // Available training hours per week
	StartDate      string   `json:"start_date"`       // YYYY-MM-DD
	IncludeRest    bool     `json:"include_rest"`     // Whether to include rest days
	TargetEventID  *uint    `json:"target_event_id"`  // Optional target event to periodize for
}

// GenerateResponse contains AI-generated workouts
type GenerateResponse struct {
	Workouts         []AIWorkout `json:"workouts"`
	Rationale        string      `json:"rationale"`          // AI's explanation
	TotalTSS         float64     `json:"total_tss"`
	RecommendationID uint        `json:"recommendation_id"`
}

// AIWorkout represents a single AI-generated workout
type AIWorkout struct {
	Title         string                   `json:"title"`
	Description   string                   `json:"description"`
	Type          string                   `json:"type"`
	ScheduledDate string                   `json:"scheduled_date"`
	Duration      int                      `json:"duration"`      // seconds
	Segments      []workout.WorkoutSegment `json:"segments"`
	EstimatedTSS  float64                  `json:"estimated_tss"`
	Notes         string                   `json:"notes"`
}

// AIRecommendation database model
type AIRecommendation struct {
	ID                uint      `gorm:"primaryKey" json:"id"`
	UserID            uint      `gorm:"not null;index" json:"user_id"`
	PromptContext     JSONB     `gorm:"type:jsonb" json:"prompt_context"`
	AIResponse        string    `json:"ai_response"`
	GeneratedWorkouts JSONB     `gorm:"type:jsonb" json:"generated_workouts"`
	Parameters        JSONB     `gorm:"type:jsonb" json:"parameters"`
	Status            string    `gorm:"default:'generated'" json:"status"`
	CreatedAt         time.Time `json:"created_at"`
}

func (AIRecommendation) TableName() string {
	return "ai_recommendations"
}

// JSONB type for PostgreSQL JSONB columns
type JSONB struct {
	Data []byte
}

// Scan implements sql.Scanner interface
func (j *JSONB) Scan(value interface{}) error {
	if value == nil {
		j.Data = []byte("{}")
		return nil
	}
	bytes, ok := value.([]byte)
	if !ok {
		return nil
	}
	j.Data = bytes
	return nil
}

// Value implements driver.Valuer interface
func (j JSONB) Value() (driver.Value, error) {
	if len(j.Data) == 0 {
		return []byte("{}"), nil
	}
	return j.Data, nil
}

// MarshalJSON implements json.Marshaler
func (j JSONB) MarshalJSON() ([]byte, error) {
	if len(j.Data) == 0 {
		return []byte("{}"), nil
	}
	return j.Data, nil
}

// UnmarshalJSON implements json.Unmarshaler
func (j *JSONB) UnmarshalJSON(data []byte) error {
	j.Data = data
	return nil
}

// UserContext contains all user data sent to AI
type UserContext struct {
	FTP            int                      `json:"ftp"`
	MaxHR          int                      `json:"max_hr"`
	RestingHR      int                      `json:"resting_hr"`
	Weight         float64                  `json:"weight"`
	TrainingGoal   string                   `json:"training_goal"`
	WeeklyHours    int                      `json:"weekly_hours"`
	RecentWorkouts []RecentWorkoutSummary   `json:"recent_workouts"`
	TrainingLoad   TrainingLoadSummary      `json:"training_load"`
	UpcomingEvents []UpcomingEventSummary   `json:"upcoming_events,omitempty"`
	TargetEvent    *UpcomingEventSummary    `json:"target_event,omitempty"`
	Nutrition      *NutritionContext        `json:"nutrition,omitempty"`
}

// NutritionContext contains nutrition data for AI
type NutritionContext struct {
	Goal           string `json:"goal"`
	DailyCalories  int    `json:"daily_calories"`
	ProteinG       int    `json:"protein_g"`
	CarbsG         int    `json:"carbs_g"`
	FatG           int    `json:"fat_g"`
	DietaryPref    string `json:"dietary_preference"`
}

// UpcomingEventSummary summarizes an upcoming race/event for AI context
type UpcomingEventSummary struct {
	Name      string  `json:"name"`
	Date      string  `json:"date"`
	EventType string  `json:"event_type"`
	Distance  float64 `json:"distance"`
	Priority  string  `json:"priority"`
	DaysAway  int     `json:"days_away"`
}

// RecentWorkoutSummary summarizes a completed workout
type RecentWorkoutSummary struct {
	Date     string  `json:"date"`
	Type     string  `json:"type"`
	Duration int     `json:"duration"`
	AvgPower int     `json:"avg_power"`
	TSS      float64 `json:"tss"`
}

// TrainingLoadSummary contains CTL/ATL/TSB metrics
type TrainingLoadSummary struct {
	CTL float64 `json:"ctl"` // Chronic Training Load (42-day EMA)
	ATL float64 `json:"atl"` // Acute Training Load (7-day EMA)
	TSB float64 `json:"tsb"` // Training Stress Balance (CTL - ATL)
}

// DeepSeek API structures
type DeepSeekRequest struct {
	Model       string            `json:"model"`
	Messages    []DeepSeekMessage `json:"messages"`
	Temperature float64           `json:"temperature"`
	MaxTokens   int               `json:"max_tokens,omitempty"`
}

type DeepSeekMessage struct {
	Role    string `json:"role"`
	Content string `json:"content"`
}

type DeepSeekResponse struct {
	Choices []struct {
		Message DeepSeekMessage `json:"message"`
	} `json:"choices"`
	Error *struct {
		Message string `json:"message"`
		Type    string `json:"type"`
	} `json:"error"`
}