package block

import (
	"strconv"

	"gno.land/p/demo/tokens/grc1155"
	"gno.land/p/nt/avl"
)

var (
	userTokenIndex = avl.NewTree() // address -> map[tid]bool
)

// addUserToken adds a token ID to user's token list
func addUserToken(user address, tid grc1155.TokenID) {
	userStr := user.String()

	// Get or create user's token map
	var tokensMap map[string]bool
	tokens, found := userTokenIndex.Get(userStr)
	if found {
		tokensMap = tokens.(map[string]bool)
	} else {
		tokensMap = make(map[string]bool)
		userTokenIndex.Set(userStr, tokensMap)
	}

	tidStr := string(tid)
	tokensMap[tidStr] = true
}

// addUserTokenBatch adds multiple token IDs to user's token list
func addUserTokenBatch(user address, tids []grc1155.TokenID) {
	userStr := user.String()

	// Get or create user's token map
	var tokensMap map[string]bool
	tokens, found := userTokenIndex.Get(userStr)
	if found {
		tokensMap = tokens.(map[string]bool)
	} else {
		tokensMap = make(map[string]bool)
		userTokenIndex.Set(userStr, tokensMap)
	}

	for _, tid := range tids {
		tidStr := string(tid)
		tokensMap[tidStr] = true
	}
}

// removeUserToken removes a token ID from user's token list if balance is 0
func removeUserToken(user address, tid grc1155.TokenID) {
	balance := BalanceOf(user, tid)
	if balance != 0 {
		return
	}

	userStr := user.String()
	tokens, found := userTokenIndex.Get(userStr)
	if !found {
		return
	}

	tokensMap := tokens.(map[string]bool)
	tidStr := string(tid)
	delete(tokensMap, tidStr)

	// Remove user entry if no tokens left
	if len(tokensMap) == 0 {
		userTokenIndex.Remove(userStr)
	}
}

// removeUserTokenBatch removes multiple token IDs from user's token list
func removeUserTokenBatch(user address, tids []grc1155.TokenID) {
	userStr := user.String()
	tokens, found := userTokenIndex.Get(userStr)
	if !found {
		return
	}

	tokensMap := tokens.(map[string]bool)
	for _, tid := range tids {
		balance := BalanceOf(user, tid)
		if balance != 0 {
			continue
		}
		tidStr := string(tid)
		delete(tokensMap, tidStr)
	}

	// Remove user entry if no tokens left
	if len(tokensMap) == 0 {
		userTokenIndex.Remove(userStr)
	}
}

// getUserTokens returns all token IDs owned by user
func getUserTokens(user address) []string {
	userStr := user.String()
	tokens, found := userTokenIndex.Get(userStr)
	if !found {
		return []string{}
	}

	tokensMap := tokens.(map[string]bool)
	result := make([]string, 0, len(tokensMap))

	for tid := range tokensMap {
		result = append(result, tid)
	}

	return result
}

// GetInventory returns all block tokens owned by user with their balances
func GetInventory(user address) []map[string]string {
	result := []map[string]string{}

	// Get all token IDs owned by user
	tids := getUserTokens(user)

	for _, tid := range tids {
		balance, err := token.BalanceOf(user, grc1155.TokenID(tid))
		if err != nil {
			continue
		}

		// Only include tokens with non-zero balance
		if balance > 0 {
			result = append(result, map[string]string{
				"id":      tid,
				"balance": strconv.FormatInt(balance, 10),
			})
		}
	}

	return result
}