package module

import (
	"context"
	"encoding/json"
	"fmt"

	gwruntime "github.com/grpc-ecosystem/grpc-gateway/runtime"
	"github.com/spf13/cobra"
	"google.golang.org/grpc"

	"cosmossdk.io/core/appmodule"
	"cosmossdk.io/x/group"
	"cosmossdk.io/x/group/client/cli"
	"cosmossdk.io/x/group/keeper"
	"cosmossdk.io/x/group/simulation"

	sdkclient "github.com/cosmos/cosmos-sdk/client"
	"github.com/cosmos/cosmos-sdk/codec"
	cdctypes "github.com/cosmos/cosmos-sdk/codec/types"
	sdk "github.com/cosmos/cosmos-sdk/types"
	"github.com/cosmos/cosmos-sdk/types/module"
	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
)

// ConsensusVersion defines the current x/group module consensus version.
const ConsensusVersion = 2

var (
	_ module.HasName               = AppModule{}
	_ module.HasAminoCodec         = AppModule{}
	_ module.HasGRPCGateway        = AppModule{}
	_ module.HasRegisterInterfaces = AppModule{}
	_ module.AppModuleSimulation   = AppModule{}
	_ module.HasGenesis            = AppModule{}
	_ module.HasInvariants         = AppModule{}

	_ appmodule.AppModule     = AppModule{}
	_ appmodule.HasEndBlocker = AppModule{}
	_ appmodule.HasServices   = AppModule{}
	_ appmodule.HasMigrations = AppModule{}
)

type AppModule struct {
	cdc      codec.Codec
	registry cdctypes.InterfaceRegistry

	keeper     keeper.Keeper
	bankKeeper group.BankKeeper
	accKeeper  group.AccountKeeper
}

// NewAppModule creates a new AppModule object
func NewAppModule(cdc codec.Codec, keeper keeper.Keeper, ak group.AccountKeeper, bk group.BankKeeper, registry cdctypes.InterfaceRegistry) AppModule {
	return AppModule{
		cdc:        cdc,
		keeper:     keeper,
		bankKeeper: bk,
		accKeeper:  ak,
		registry:   registry,
	}
}

// IsAppModule implements the appmodule.AppModule interface.
func (AppModule) IsAppModule() {}

// Name returns the group module's name.
func (am AppModule) Name() string {
	return group.ModuleName
}

// GetTxCmd returns the transaction commands for the group module
func (am AppModule) GetTxCmd() *cobra.Command {
	return cli.TxCmd(am.Name())
}

// RegisterGRPCGatewayRoutes registers the gRPC Gateway routes for the group module.
func (am AppModule) RegisterGRPCGatewayRoutes(clientCtx sdkclient.Context, mux *gwruntime.ServeMux) {
	if err := group.RegisterQueryHandlerClient(context.Background(), mux, group.NewQueryClient(clientCtx)); err != nil {
		panic(err)
	}
}

// RegisterInterfaces registers the group module's interface types
func (AppModule) RegisterInterfaces(registry cdctypes.InterfaceRegistry) {
	group.RegisterInterfaces(registry)
}

// RegisterLegacyAminoCodec registers the group module's types for the given codec.
func (AppModule) RegisterLegacyAminoCodec(cdc *codec.LegacyAmino) {
	group.RegisterLegacyAminoCodec(cdc)
}

// RegisterInvariants does nothing, there are no invariants to enforce
func (am AppModule) RegisterInvariants(ir sdk.InvariantRegistry) {
	keeper.RegisterInvariants(ir, am.keeper)
}

// RegisterServices registers module services.
func (am AppModule) RegisterServices(registrar grpc.ServiceRegistrar) error {
	group.RegisterMsgServer(registrar, am.keeper)
	group.RegisterQueryServer(registrar, am.keeper)

	return nil
}

// RegisterMigrations registers module migrations
func (am AppModule) RegisterMigrations(mr appmodule.MigrationRegistrar) error {
	m := keeper.NewMigrator(am.keeper)
	if err := mr.Register(group.ModuleName, 1, m.Migrate1to2); err != nil {
		return fmt.Errorf("failed to migrate x/%s from version 1 to 2: %v", group.ModuleName, err)
	}

	return nil
}

// ConsensusVersion implements HasConsensusVersion
func (AppModule) ConsensusVersion() uint64 { return ConsensusVersion }

// EndBlock implements the group module's EndBlock.
func (am AppModule) EndBlock(ctx context.Context) error {
	return am.keeper.EndBlocker(ctx)
}

// DefaultGenesis returns default genesis state as raw bytes for the group module.
func (AppModule) DefaultGenesis(cdc codec.JSONCodec) json.RawMessage {
	return cdc.MustMarshalJSON(group.NewGenesisState())
}

// ValidateGenesis performs genesis state validation for the group module.
func (AppModule) ValidateGenesis(cdc codec.JSONCodec, config sdkclient.TxEncodingConfig, bz json.RawMessage) error {
	var data group.GenesisState
	if err := cdc.UnmarshalJSON(bz, &data); err != nil {
		return fmt.Errorf("failed to unmarshal %s genesis state: %w", group.ModuleName, err)
	}
	return data.Validate()
}

// InitGenesis performs genesis initialization for the group module.
func (am AppModule) InitGenesis(ctx context.Context, cdc codec.JSONCodec, data json.RawMessage) {
	am.keeper.InitGenesis(ctx, cdc, data)
}

// ExportGenesis returns the exported genesis state as raw bytes for the group module.
func (am AppModule) ExportGenesis(ctx context.Context, cdc codec.JSONCodec) json.RawMessage {
	gs := am.keeper.ExportGenesis(ctx, cdc)
	return cdc.MustMarshalJSON(gs)
}

// GenerateGenesisState creates a randomized GenState of the group module.
func (AppModule) GenerateGenesisState(simState *module.SimulationState) {
	simulation.RandomizedGenState(simState)
}

// RegisterStoreDecoder registers a decoder for group module's types
func (am AppModule) RegisterStoreDecoder(sdr simtypes.StoreDecoderRegistry) {
	sdr[group.StoreKey] = simulation.NewDecodeStore(am.cdc)
}

// WeightedOperations returns the all the gov module operations with their respective weights.
func (am AppModule) WeightedOperations(simState module.SimulationState) []simtypes.WeightedOperation {
	return simulation.WeightedOperations(
		am.registry,
		simState.AppParams, simState.Cdc, simState.TxConfig,
		am.accKeeper, am.bankKeeper, am.keeper, am.cdc,
	)
}