package rest

import (
	"fmt"
	"net/http"

	"github.com/gorilla/mux"

	"github.com/cosmos/cosmos-sdk/client"
	"github.com/cosmos/cosmos-sdk/client/tx"
	"github.com/cosmos/cosmos-sdk/types/rest"
	gcutils "github.com/cosmos/cosmos-sdk/x/gov/client/utils"
	"github.com/cosmos/cosmos-sdk/x/gov/types"
)

func registerTxHandlers(clientCtx client.Context, r *mux.Router, phs []ProposalRESTHandler) {
	propSubRtr := r.PathPrefix("/gov/proposals").Subrouter()
	for _, ph := range phs {
		propSubRtr.HandleFunc(fmt.Sprintf("/%s", ph.SubRoute), ph.Handler).Methods("POST")
	}

	r.HandleFunc("/gov/proposals", newPostProposalHandlerFn(clientCtx)).Methods("POST")
	r.HandleFunc(fmt.Sprintf("/gov/proposals/{%s}/deposits", RestProposalID), newDepositHandlerFn(clientCtx)).Methods("POST")
	r.HandleFunc(fmt.Sprintf("/gov/proposals/{%s}/votes", RestProposalID), newVoteHandlerFn(clientCtx)).Methods("POST")
}

func newPostProposalHandlerFn(clientCtx client.Context) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var req PostProposalReq
		if !rest.ReadRESTReq(w, r, clientCtx.LegacyAmino, &req) {
			return
		}

		req.BaseReq = req.BaseReq.Sanitize()
		if !req.BaseReq.ValidateBasic(w) {
			return
		}

		proposalType := gcutils.NormalizeProposalType(req.ProposalType)
		content := types.ContentFromProposalType(req.Title, req.Description, proposalType)

		msg, err := types.NewMsgSubmitProposal(content, req.InitialDeposit, req.Proposer)
		if rest.CheckBadRequestError(w, err) {
			return
		}
		if rest.CheckBadRequestError(w, msg.ValidateBasic()) {
			return
		}

		tx.WriteGeneratedTxResponse(clientCtx, w, req.BaseReq, msg)
	}
}

func newDepositHandlerFn(clientCtx client.Context) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		vars := mux.Vars(r)
		strProposalID := vars[RestProposalID]

		if len(strProposalID) == 0 {
			rest.WriteErrorResponse(w, http.StatusBadRequest, "proposalId required but not specified")
			return
		}

		proposalID, ok := rest.ParseUint64OrReturnBadRequest(w, strProposalID)
		if !ok {
			return
		}

		var req DepositReq
		if !rest.ReadRESTReq(w, r, clientCtx.LegacyAmino, &req) {
			return
		}

		req.BaseReq = req.BaseReq.Sanitize()
		if !req.BaseReq.ValidateBasic(w) {
			return
		}

		// create the message
		msg := types.NewMsgDeposit(req.Depositor, proposalID, req.Amount)
		if rest.CheckBadRequestError(w, msg.ValidateBasic()) {
			return
		}

		tx.WriteGeneratedTxResponse(clientCtx, w, req.BaseReq, msg)
	}
}

func newVoteHandlerFn(clientCtx client.Context) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		vars := mux.Vars(r)
		strProposalID := vars[RestProposalID]

		if len(strProposalID) == 0 {
			rest.WriteErrorResponse(w, http.StatusBadRequest, "proposalId required but not specified")
			return
		}

		proposalID, ok := rest.ParseUint64OrReturnBadRequest(w, strProposalID)
		if !ok {
			return
		}

		var req VoteReq
		if !rest.ReadRESTReq(w, r, clientCtx.LegacyAmino, &req) {
			return
		}

		req.BaseReq = req.BaseReq.Sanitize()
		if !req.BaseReq.ValidateBasic(w) {
			return
		}

		voteOption, err := types.VoteOptionFromString(gcutils.NormalizeVoteOption(req.Option))
		if rest.CheckBadRequestError(w, err) {
			return
		}

		// create the message
		msg := types.NewMsgVote(req.Voter, proposalID, voteOption)
		if rest.CheckBadRequestError(w, msg.ValidateBasic()) {
			return
		}

		tx.WriteGeneratedTxResponse(clientCtx, w, req.BaseReq, msg)
	}
}