package realdebrid

import (
	"fmt"
	"sync"
)

type Token struct {
	value   string
	expired bool
}

type DownloadTokenManager struct {
	tokens  []Token
	current int
	mu      sync.RWMutex
}

// NewDownloadTokenManager initializes a new DownloadTokenManager with the given tokens.
func NewDownloadTokenManager(tokenStrings []string) *DownloadTokenManager {
	tokens := make([]Token, len(tokenStrings))
	for i, t := range tokenStrings {
		tokens[i] = Token{value: t, expired: false}
	}
	return &DownloadTokenManager{tokens: tokens, current: 0}
}

// GetCurrentToken returns the current non-expired token.
func (dtm *DownloadTokenManager) GetCurrentToken() (string, error) {
	dtm.mu.RLock()
	defer dtm.mu.RUnlock()

	for {
		if !dtm.tokens[dtm.current].expired {
			return dtm.tokens[dtm.current].value, nil
		}

		dtm.current = (dtm.current + 1) % len(dtm.tokens)

		if dtm.current == 0 {
			return "", fmt.Errorf("all tokens are bandwidth-limited")
		}
	}
}

// SetTokenAsExpired sets the specified token as expired.
func (dtm *DownloadTokenManager) SetTokenAsExpired(token string) error {
	dtm.mu.Lock()
	defer dtm.mu.Unlock()

	for i, t := range dtm.tokens {
		if t.value == token {
			dtm.tokens[i].expired = true
			return nil
		}
	}

	return fmt.Errorf("token not found")
}

// ResetAllTokens resets all tokens to expired=false.
func (dtm *DownloadTokenManager) ResetAllTokens() {
	dtm.mu.Lock()
	defer dtm.mu.Unlock()

	for i := range dtm.tokens {
		dtm.tokens[i].expired = false
	}
	dtm.current = 0
}