package domain

import (
	"context"
	"time"

	"gorm.io/datatypes"
	"gorm.io/gorm"
)

type MatchStatus string

const (
	MatchStatusSuggested   MatchStatus = "suggested"
	MatchStatusNegotiating MatchStatus = "negotiating"
	MatchStatusReserved    MatchStatus = "reserved"
	MatchStatusContracted  MatchStatus = "contracted"
	MatchStatusLive        MatchStatus = "live"
	MatchStatusFailed      MatchStatus = "failed"
	MatchStatusCancelled   MatchStatus = "cancelled"
)

// TransportationEstimate represents transportation cost and feasibility
type TransportationEstimate struct {
	CostPerYear      float64 `json:"cost_per_year"`
	Method           string  `json:"method"`            // piping, truck, tanker
	FeasibilityScore float64 `json:"feasibility_score"` // 0-1
}

// RiskAssessment represents different risk factors
type RiskAssessment struct {
	TechnicalRisk    float64 `json:"technical_risk"`              // 0-1
	RegulatoryRisk   float64 `json:"regulatory_risk"`             // 0-1
	MarketRisk       float64 `json:"market_risk"`                 // 0-1
	CounterpartyRisk float64 `json:"counterparty_risk,omitempty"` // 0-1
}

// EconomicImpact represents economic and environmental impact
type EconomicImpact struct {
	AnnualSavings    float64 `json:"annual_savings"`     // €/year
	NPV              float64 `json:"npv"`                // Net Present Value
	IRR              float64 `json:"irr"`                // Internal Rate of Return (%)
	PaybackYears     float64 `json:"payback_years"`      // years
	CO2AvoidedTonnes float64 `json:"co2_avoided_tonnes"` // tonnes/year
	CapexRequired    float64 `json:"capex_required"`     // initial investment
	OpexPerYear      float64 `json:"opex_per_year"`      // annual operational cost
}

// NegotiationHistoryEntry represents a single entry in match negotiation history
type NegotiationHistoryEntry struct {
	ID          string         `gorm:"primaryKey;type:text"`
	MatchID     string         `gorm:"not null;type:text;index"`
	Timestamp   time.Time      `gorm:"not null;index"`
	ActorID     string         `gorm:"type:text;index"`           // User who made the change
	Action      string         `gorm:"not null;type:varchar(50)"` // proposed, accepted, rejected, counter_offered, etc.
	Notes       string         `gorm:"type:text"`
	OldValue    datatypes.JSON `gorm:"type:jsonb"`              // Previous value (for status changes, etc.)
	NewValue    datatypes.JSON `gorm:"type:jsonb"`              // New value
	Attachments datatypes.JSON `gorm:"type:jsonb;default:'[]'"` // File URLs, documents
	Metadata    datatypes.JSON `gorm:"type:jsonb;default:'{}'"` // Additional context

	// Relationships
	Match *Match `gorm:"foreignKey:MatchID"`
}

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

// Enhanced ContractDetails represents contract information when match is formalized
type ContractDetails struct {
	ContractID       string         `json:"contract_id,omitempty"`
	SignedAt         *time.Time     `json:"signed_at,omitempty"`
	EffectiveFrom    *time.Time     `json:"effective_from,omitempty"`
	TerminationDate  *time.Time     `json:"termination_date,omitempty"`
	ValuePerYear     float64        `json:"value_per_year,omitempty"`
	TermsURL         string         `json:"terms_url,omitempty"`
	PaymentTerms     string         `json:"payment_terms,omitempty"`
	TerminationTerms string         `json:"termination_terms,omitempty"`
	Signatures       datatypes.JSON `gorm:"type:jsonb;default:'[]'"` // Signer information
}

// Match represents a potential or actual resource exchange between two organizations
type Match struct {
	ID               string      `gorm:"primaryKey;type:text"`
	SourceResourceID string      `gorm:"type:text;not null;index:idx_match_resources"`
	TargetResourceID string      `gorm:"type:text;not null;index:idx_match_resources"`
	Status           MatchStatus `gorm:"type:varchar(50);not null;default:'suggested';index"`

	// Scoring
	CompatibilityScore   float64 `gorm:"type:double precision;not null;index"` // Overall score 0-1
	TemporalOverlapScore float64 `gorm:"type:double precision"`                // Availability overlap 0-1
	QualityScore         float64 `gorm:"type:double precision"`                // Quality compatibility 0-1
	EconomicValue        float64 `gorm:"type:double precision;index"`          // Estimated annual value €
	DistanceKm           float64 `gorm:"type:double precision;index"`

	// Priority and reservation
	Priority      int        `gorm:"type:integer;default:5;check:priority BETWEEN 1 AND 10"`
	ReservedUntil *time.Time `gorm:"type:timestamp with time zone"`

	// Enhanced contract details (replacing JSONB)
	ContractDetails *ContractDetails `gorm:"embedded;embeddedPrefix:contract_"`

	// Failure and cancellation tracking
	FailureReason string     `gorm:"type:text"`
	CancelledBy   string     `gorm:"type:text;index"` // User ID who cancelled
	CancelledAt   *time.Time `gorm:"type:timestamp with time zone"`

	// Negotiation history (replacing JSONB with proper relationship)
	NegotiationHistory []NegotiationHistoryEntry `gorm:"foreignKey:MatchID"`

	// Legacy JSONB fields (keeping for backward compatibility during migration)
	TransportationEstimate datatypes.JSON `gorm:"type:jsonb"`              // TransportationEstimate
	RiskAssessment         datatypes.JSON `gorm:"type:jsonb"`              // RiskAssessment
	EconomicImpact         datatypes.JSON `gorm:"type:jsonb"`              // EconomicImpact
	History                datatypes.JSON `gorm:"default:'[]';type:jsonb"` // []MatchHistoryEntry (deprecated)

	// Optimistic locking
	Version int `gorm:"type:integer;default:1"`

	// Timestamps
	CreatedAt time.Time `gorm:"autoCreateTime;index"`
	UpdatedAt time.Time `gorm:"autoUpdateTime"`

	// Associations
	SourceResource *ResourceFlow `gorm:"foreignKey:SourceResourceID"`
	TargetResource *ResourceFlow `gorm:"foreignKey:TargetResourceID"`
}

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

// BeforeUpdate increments version for optimistic locking
func (m *Match) BeforeUpdate(db *gorm.DB) error {
	m.Version++
	return nil
}

type MatchRepository interface {
	Create(ctx context.Context, match *Match) error
	GetByID(ctx context.Context, id string) (*Match, error)
	GetByResourceID(ctx context.Context, resourceID string) ([]*Match, error)
	GetByOrganizationID(ctx context.Context, organizationID string) ([]*Match, error)
	GetByStatus(ctx context.Context, status MatchStatus) ([]*Match, error)
	GetTopMatches(ctx context.Context, limit int) ([]*Match, error) // Order by compatibility score
	Update(ctx context.Context, match *Match) error
	Delete(ctx context.Context, id string) error
	// Conflict resolution
	CheckReservationConflicts(ctx context.Context, resourceID string) ([]*Match, error)
	UpdateStatus(ctx context.Context, matchID string, newStatus MatchStatus, actor string, notes string) error

	// Advanced queries for event-driven matching
	GetByOrganizationIDAndStatus(ctx context.Context, orgID string, status MatchStatus) ([]*Match, error)
	GetExpiredReservations() ([]*Match, error)
	GetPendingNegotiations() ([]*Match, error)
}

// NegotiationHistoryRepository defines the interface for negotiation history data access
type NegotiationHistoryRepository interface {
	Create(ctx context.Context, entry *NegotiationHistoryEntry) error
	GetByMatchID(ctx context.Context, matchID string) ([]*NegotiationHistoryEntry, error)
	GetByActorID(ctx context.Context, actorID string) ([]*NegotiationHistoryEntry, error)
	GetRecentActivity(ctx context.Context, limit int) ([]*NegotiationHistoryEntry, error)
}