package extraction

import (
	"context"
	"errors"
	"time"
)

type Fulfillment string

const (
	Partial      Fulfillment = "partial"
	AllOrNothing Fulfillment = "allOrNothing"
)

type State string

const (
	Available State = "AVAILABLE"
	Extracted State = "EXTRACTED"
)

var (
	ErrInsufficientProxies = errors.New("insufficient proxies")
	ErrIdempotencyConflict = errors.New("idempotency key was reused with a different extraction request")
	ErrInvalidCommand      = errors.New("invalid extraction command")
	ErrStoreUnavailable    = errors.New("extraction store unavailable")
)

type Candidate struct {
	ID            string
	Protocol      string
	Host          string
	Port          uint16
	Username      string
	Password      string
	Region        string
	Carrier       string
	Upstream      string
	OwnerWorkerID string
	URL           string
	State         State
	ExpiresAt     time.Time
	LastCheckedAt time.Time
}

type Command struct {
	RequestID         string
	ClientID          string
	SourceIP          string
	IdempotencyKey    string
	IdempotencyTTL    time.Duration
	Requested         int
	Fulfillment       Fulfillment
	Now               time.Time
	MinRemainingTTL   time.Duration
	MaxHealthCheckAge time.Duration
	ReserveForGateway int
	Protocols         []string
	Regions           []string
	Carriers          []string
	Upstreams         []string
}

type Result struct {
	Requested   int
	Returned    int
	ExtractedAt time.Time
	Items       []Candidate
}

// Store atomically consumes proxies from a bounded, ephemeral activity pool.
// Implementations must not require durable per-proxy extraction records.
type Store interface {
	Extract(context.Context, Command) (Result, error)
}