package domain

import (
	"context"
	"fmt"
	"time"

	"github.com/lib/pq"
	"gorm.io/datatypes"
)

// CommunityListingType defines the type of community listing
type CommunityListingType string

const (
	CommunityListingTypeProduct CommunityListingType = "product"
	CommunityListingTypeService CommunityListingType = "service"
	CommunityListingTypeTool    CommunityListingType = "tool"
	CommunityListingTypeSkill   CommunityListingType = "skill"
	CommunityListingTypeNeed    CommunityListingType = "need"
)

// CommunityListingPriceType defines how the listing is priced
type CommunityListingPriceType string

const (
	CommunityListingPriceTypeFree   CommunityListingPriceType = "free"
	CommunityListingPriceTypeSale   CommunityListingPriceType = "sale"
	CommunityListingPriceTypeRent   CommunityListingPriceType = "rent"
	CommunityListingPriceTypeTrade  CommunityListingPriceType = "trade"
	CommunityListingPriceTypeBorrow CommunityListingPriceType = "borrow"
)

// CommunityListingStatus defines the status of a listing
type CommunityListingStatus string

const (
	CommunityListingStatusActive    CommunityListingStatus = "active"
	CommunityListingStatusReserved  CommunityListingStatus = "reserved"
	CommunityListingStatusCompleted CommunityListingStatus = "completed"
	CommunityListingStatusArchived  CommunityListingStatus = "archived"
)

// CommunityListingCondition defines the condition of a product/tool
type CommunityListingCondition string

const (
	CommunityListingConditionNew         CommunityListingCondition = "new"
	CommunityListingConditionLikeNew     CommunityListingCondition = "like_new"
	CommunityListingConditionGood        CommunityListingCondition = "good"
	CommunityListingConditionFair        CommunityListingCondition = "fair"
	CommunityListingConditionNeedsRepair CommunityListingCondition = "needs_repair"
)

// CommunityListing represents a listing created by a community member (user)
// This extends the platform beyond business-only listings to enable "I Don't Know Who Has What" for citizens
type CommunityListing struct {
	ID     string `gorm:"primaryKey;type:text"`
	UserID string `gorm:"not null;type:text;index"` // References users table
	User   *User  `gorm:"foreignKey:UserID"`        // User who created the listing

	// Listing Information
	Title       string               `gorm:"not null;type:varchar(255);index"`
	Description string               `gorm:"type:text"`
	ListingType CommunityListingType `gorm:"not null;type:varchar(50);index"`
	Category    string               `gorm:"not null;type:varchar(100);index"`
	Subcategory string               `gorm:"type:varchar(100)"`

	// For Products/Tools
	Condition *CommunityListingCondition `gorm:"type:varchar(50)"`   // Condition of item (new, like_new, good, etc.)
	Price     *float64                   `gorm:"type:decimal(10,2)"` // NULL = free
	PriceType *CommunityListingPriceType `gorm:"type:varchar(50)"`   // free, sale, rent, trade, borrow

	// For Services/Skills
	ServiceType *string  `gorm:"type:varchar(50)"`   // 'offering' or 'seeking'
	Rate        *float64 `gorm:"type:decimal(10,2)"` // Rate for service/skill
	RateType    *string  `gorm:"type:varchar(50)"`   // 'hourly', 'fixed', 'negotiable', 'free', 'trade'

	// Availability
	AvailabilityStatus   string         `gorm:"type:varchar(20);default:'available';index"` // available, limited, reserved, unavailable
	AvailabilitySchedule datatypes.JSON `gorm:"type:jsonb"`                                 // Time-based availability schedule
	QuantityAvailable    *int           `gorm:"type:integer"`                               // For products (NULL = unlimited)

	// Location
	Location          Point    `gorm:"type:geometry(Point,4326)"` // PostGIS geometry point
	PickupAvailable   bool     `gorm:"default:true"`              // Can be picked up
	DeliveryAvailable bool     `gorm:"default:false"`             // Can be delivered
	DeliveryRadiusKm  *float64 `gorm:"type:decimal(5,2)"`         // Delivery radius in km

	// Media
	Images pq.StringArray `gorm:"type:text[]"` // Array of image URLs

	// Metadata
	Tags           pq.StringArray `gorm:"type:text[]"` // Searchable tags array
	SearchKeywords string         `gorm:"type:text"`   // Full-text search keywords

	// Trust & Verification
	UserRating  *float64 `gorm:"type:decimal(3,2)"` // Average rating from reviews (0-5)
	ReviewCount int      `gorm:"default:0"`         // Number of reviews
	Verified    bool     `gorm:"default:false"`     // Platform verification

	// Status
	Status CommunityListingStatus `gorm:"type:varchar(20);default:'active';index"` // active, reserved, completed, archived

	// Timestamps
	CreatedAt time.Time  `gorm:"autoCreateTime"`
	UpdatedAt time.Time  `gorm:"autoUpdateTime"`
	ExpiresAt *time.Time `gorm:"type:timestamp with time zone"` // Auto-archive after expiration
}

// TableName specifies the table name for GORM
func (CommunityListing) TableName() string {
	return "community_listings"
}

// Validate performs business rule validation
func (cl *CommunityListing) Validate() error {
	if cl.Title == "" {
		return fmt.Errorf("listing title cannot be empty")
	}
	if cl.Category == "" {
		return fmt.Errorf("listing category cannot be empty")
	}
	if cl.UserID == "" {
		return fmt.Errorf("user ID cannot be empty")
	}
	if cl.Price != nil && *cl.Price < 0 {
		return fmt.Errorf("price cannot be negative")
	}
	if cl.Rate != nil && *cl.Rate < 0 {
		return fmt.Errorf("rate cannot be negative")
	}
	return nil
}

// CommunityListingRepository defines operations for community listing management
type CommunityListingRepository interface {
	Create(ctx context.Context, listing *CommunityListing) error
	GetByID(ctx context.Context, id string) (*CommunityListing, error)
	GetByUser(ctx context.Context, userID string) ([]*CommunityListing, error)
	GetByType(ctx context.Context, listingType CommunityListingType) ([]*CommunityListing, error)
	GetByCategory(ctx context.Context, category string) ([]*CommunityListing, error)
	SearchWithLocation(ctx context.Context, query string, location *Point, radiusKm float64) ([]*CommunityListing, error)
	GetNearby(ctx context.Context, lat, lng, radiusKm float64) ([]*CommunityListing, error)
	Update(ctx context.Context, listing *CommunityListing) error
	Delete(ctx context.Context, id string) error
	GetAll(ctx context.Context) ([]*CommunityListing, error)
}