package rest

import (
	"fmt"
	"net/http"

	"github.com/cosmos/cosmos-sdk/client/context"
	"github.com/cosmos/cosmos-sdk/client/utils"
	"github.com/cosmos/cosmos-sdk/codec"
	sdk "github.com/cosmos/cosmos-sdk/types"
	"github.com/cosmos/cosmos-sdk/x/auth"
	authcmd "github.com/cosmos/cosmos-sdk/x/auth/client/cli"

	"github.com/gorilla/mux"
)

// register REST routes
func RegisterRoutes(cliCtx context.CLIContext, r *mux.Router, cdc *codec.Codec, storeName string) {
	r.HandleFunc(
		"/accounts/{address}",
		QueryAccountRequestHandlerFn(storeName, cdc, authcmd.GetAccountDecoder(cdc), cliCtx),
	).Methods("GET")
	r.HandleFunc(
		"/bank/balances/{address}",
		QueryBalancesRequestHandlerFn(storeName, cdc, authcmd.GetAccountDecoder(cdc), cliCtx),
	).Methods("GET")
	r.HandleFunc(
		"/tx/sign",
		SignTxRequestHandlerFn(cdc, cliCtx),
	).Methods("POST")
}

// query accountREST Handler
func QueryAccountRequestHandlerFn(
	storeName string, cdc *codec.Codec,
	decoder auth.AccountDecoder, cliCtx context.CLIContext,
) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		vars := mux.Vars(r)
		bech32addr := vars["address"]

		addr, err := sdk.AccAddressFromBech32(bech32addr)
		if err != nil {
			utils.WriteErrorResponse(w, http.StatusInternalServerError, err.Error())
			return
		}

		res, err := cliCtx.QueryStore(auth.AddressStoreKey(addr), storeName)
		if err != nil {
			utils.WriteErrorResponse(w, http.StatusInternalServerError, fmt.Sprintf("couldn't query account. Error: %s", err.Error()))
			return
		}

		// the query will return empty if there is no data for this account
		if len(res) == 0 {
			w.WriteHeader(http.StatusNoContent)
			return
		}

		// decode the value
		account, err := decoder(res)
		if err != nil {
			utils.WriteErrorResponse(w, http.StatusInternalServerError, fmt.Sprintf("couldn't parse query result. Result: %s. Error: %s", res, err.Error()))
			return
		}

		utils.PostProcessResponse(w, cdc, account)
	}
}

// query accountREST Handler
func QueryBalancesRequestHandlerFn(
	storeName string, cdc *codec.Codec,
	decoder auth.AccountDecoder, cliCtx context.CLIContext,
) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		vars := mux.Vars(r)
		bech32addr := vars["address"]

		addr, err := sdk.AccAddressFromBech32(bech32addr)
		if err != nil {
			utils.WriteErrorResponse(w, http.StatusInternalServerError, err.Error())
			return
		}

		res, err := cliCtx.QueryStore(auth.AddressStoreKey(addr), storeName)
		if err != nil {
			utils.WriteErrorResponse(w, http.StatusInternalServerError, fmt.Sprintf("couldn't query account. Error: %s", err.Error()))
			return
		}

		// the query will return empty if there is no data for this account
		if len(res) == 0 {
			w.WriteHeader(http.StatusNoContent)
			return
		}

		// decode the value
		account, err := decoder(res)
		if err != nil {
			utils.WriteErrorResponse(w, http.StatusInternalServerError, fmt.Sprintf("couldn't parse query result. Result: %s. Error: %s", res, err.Error()))
			return
		}

		utils.PostProcessResponse(w, cdc, account.GetCoins())
	}
}