package handlers

import (
	"encoding/json"
	"net/http"
	"time"
)

type FinanceTransactionListRequest struct {
	Filter struct {
		Since           string   `json:"since"`
		To              string   `json:"to"`
		TransactionType string   `json:"transaction_type"`
		PostingNumber   []string `json:"posting_number"`
	} `json:"filter"`
	Limit int `json:"limit"`
}

type Transaction struct {
	TransactionType string            `json:"transaction_type"`
	Amount          float64           `json:"amount"`
	CurrencyCode    string            `json:"currency_code"`
	PostingNumber   string            `json:"posting_number,omitempty"`
	OrderID         int64             `json:"order_id,omitempty"`
	Items           []TransactionItem `json:"items,omitempty"`
	CreatedAt       string            `json:"created_at"`
}

type TransactionItem struct {
	Type      string  `json:"type"`
	Amount    float64 `json:"amount"`
	Quantity  int     `json:"quantity,omitempty"`
	ProductID int64   `json:"product_id,omitempty"`
	OfferID   string  `json:"offer_id,omitempty"`
}

func FinanceTransactionList(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", 405)
		return
	}

	var req FinanceTransactionListRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeError(w, 400, "invalid json")
		return
	}

	transactions := GetTransactionsFixtures()

	if req.Filter.Since != "" {
		sinceTs := parseTimeOrZero(req.Filter.Since)
		filtered := make([]Transaction, 0)
		for _, t := range transactions {
			ts := parseTimeOrZero(t.CreatedAt)
			if ts >= sinceTs {
				filtered = append(filtered, t)
			}
		}
		transactions = filtered
	}

	if req.Filter.To != "" {
		toTs := parseTimeOrZero(req.Filter.To)
		filtered := make([]Transaction, 0)
		for _, t := range transactions {
			ts := parseTimeOrZero(t.CreatedAt)
			if ts <= toTs {
				filtered = append(filtered, t)
			}
		}
		transactions = filtered
	}

	if req.Filter.TransactionType != "" {
		filtered := make([]Transaction, 0)
		for _, t := range transactions {
			if t.TransactionType == req.Filter.TransactionType {
				filtered = append(filtered, t)
			}
		}
		transactions = filtered
	}

	if len(req.Filter.PostingNumber) > 0 {
		filtered := make([]Transaction, 0)
		for _, t := range transactions {
			for _, num := range req.Filter.PostingNumber {
				if t.PostingNumber == num {
					filtered = append(filtered, t)
					break
				}
			}
		}
		transactions = filtered
	}

	if req.Limit == 0 {
		req.Limit = 100
	}

	if len(transactions) > req.Limit {
		transactions = transactions[:req.Limit]
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]any{
		"transactions": transactions,
		"total":        len(transactions),
	})
}

type FinancePayoutListRequest struct {
	Filter struct {
		Since string `json:"since"`
		To    string `json:"to"`
	} `json:"filter"`
	Limit int `json:"limit"`
}

type Payout struct {
	PayoutID        int64   `json:"payout_id"`
	Type            string  `json:"type"`
	Status          string  `json:"status"`
	Amount          float64 `json:"amount"`
	CurrencyCode    string  `json:"currency_code"`
	CreatedAt       string  `json:"created_at"`
	OperationsCount int     `json:"operations_count"`
}

func FinancePayoutList(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", 405)
		return
	}

	var req FinancePayoutListRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeError(w, 400, "invalid json")
		return
	}

	payouts := GetPayoutsFixtures()

	if req.Filter.Since != "" {
		sinceTs := parseTimeOrZero(req.Filter.Since)
		filtered := make([]Payout, 0)
		for _, p := range payouts {
			ts := parseTimeOrZero(p.CreatedAt)
			if ts >= sinceTs {
				filtered = append(filtered, p)
			}
		}
		payouts = filtered
	}

	if req.Filter.To != "" {
		toTs := parseTimeOrZero(req.Filter.To)
		filtered := make([]Payout, 0)
		for _, p := range payouts {
			ts := parseTimeOrZero(p.CreatedAt)
			if ts <= toTs {
				filtered = append(filtered, p)
			}
		}
		payouts = filtered
	}

	if req.Limit == 0 {
		req.Limit = 100
	}

	if len(payouts) > req.Limit {
		payouts = payouts[:req.Limit]
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]any{
		"payouts": payouts,
		"total":   len(payouts),
	})
}

type AnalyticsDataRequest struct {
	DateFrom  string   `json:"date_from"`
	DateTo    string   `json:"date_to"`
	Metrics   []string `json:"metrics"`
	Dimension []string `json:"dimension"`
}

func AnalyticsData(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", 405)
		return
	}

	var req AnalyticsDataRequest
	_ = json.NewDecoder(r.Body).Decode(&req)

	results := []map[string]any{
		{
			"date":         time.Now().Format("2006-01-02"),
			"orders_count": 42,
			"revenue":      125000.50,
			"avg_order":    2976.20,
		},
	}
	if req.DateFrom != "" {
		results[0]["date_from"] = req.DateFrom
	}
	if req.DateTo != "" {
		results[0]["date_to"] = req.DateTo
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]any{
		"data":  results,
		"total": 1,
	})
}

type TurnoverStocksRequest struct {
	Date string   `json:"date"`
	SKU  []string `json:"sku"`
}

type TurnoverStocksResponse struct {
	Items []struct {
		SKU                string `json:"sku"`
		ProductID          int64  `json:"product_id"`
		OnHand             int    `json:"orders_count_canceled"`
		Reserved           int    `json:"reserved"`
		InWayToCustomer    int    `json:"in_way_to_customer"`
		InWayFromCustomer  int    `json:"in_way_from_customer"`
	} `json:"items"`
}

func TurnoverStocks(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", 405)
		return
	}

	var req TurnoverStocksRequest
	_ = json.NewDecoder(r.Body).Decode(&req)

	if len(req.SKU) > 0 {
		_ = req.SKU
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(TurnoverStocksResponse{
		Items: []struct {
			SKU                string `json:"sku"`
			ProductID          int64  `json:"product_id"`
			OnHand             int    `json:"orders_count_canceled"`
			Reserved           int    `json:"reserved"`
			InWayToCustomer    int    `json:"in_way_to_customer"`
			InWayFromCustomer  int    `json:"in_way_from_customer"`
		}{
			{SKU: "TEST-SKU-001", ProductID: 99001234001, OnHand: 150, Reserved: 0, InWayToCustomer: 10, InWayFromCustomer: 2},
			{SKU: "TEST-SKU-002", ProductID: 99001234002, OnHand: 75, Reserved: 5, InWayToCustomer: 15, InWayFromCustomer: 1},
		},
	})
}