package autotest

import (
	"encoding/json"
	"fmt"
	"strings"
	"time"

	"powerpod/gotool/pb"
)

// MasterClient talks to the powerpod master over UART (implemented by main.serialPort).
type MasterClient interface {
	GetVersion() (*pb.VersionResponse, error)
	ListClients() ([]*pb.ClientInfo, error)
	AccelDeadzone(req *pb.AccelDeadzoneRequest) (*pb.AccelDeadzoneResponse, error)
	EspnowUnicastTest(clientID, seq uint32) (*pb.EspNowUnicastTestResponse, error)
}

type StepResult struct {
	Index   int
	Name    string
	Command string
	Pass    bool
	Detail  string
}

type RunResult struct {
	ConfigID   string
	ScenarioID string
	Steps      []StepResult
	Passed     int
	Failed     int
}

func Run(bench *Bench, sc *Scenario, client MasterClient) (*RunResult, error) {
	if sc.ConfigID != bench.ID {
		return nil, fmt.Errorf("scenario %q expects config %q, got %q", sc.ID, sc.ConfigID, bench.ID)
	}

	res := &RunResult{ConfigID: bench.ID, ScenarioID: sc.ID}
	for i, step := range sc.Steps {
		sr := StepResult{Index: i + 1, Name: step.Name, Command: step.Command}
		if step.Name == "" {
			sr.Name = fmt.Sprintf("step %d", i+1)
		}

		if step.DelayMS > 0 && step.Command == "" {
			time.Sleep(time.Duration(step.DelayMS) * time.Millisecond)
			sr.Pass = true
			sr.Detail = fmt.Sprintf("delay %d ms", step.DelayMS)
			res.Steps = append(res.Steps, sr)
			res.Passed++
			continue
		}

		if step.Command == "" {
			sr.Pass = false
			sr.Detail = "step needs command or delay_ms"
			res.Steps = append(res.Steps, sr)
			res.Failed++
			continue
		}

		if step.DelayMS > 0 {
			time.Sleep(time.Duration(step.DelayMS) * time.Millisecond)
		}

		err := runStep(bench, step, client)
		if err != nil {
			sr.Pass = false
			sr.Detail = err.Error()
			res.Failed++
		} else {
			sr.Pass = true
			sr.Detail = "ok"
			res.Passed++
		}
		res.Steps = append(res.Steps, sr)
	}
	return res, nil
}

func runStep(bench *Bench, step Step, client MasterClient) error {
	cmd := strings.ToLower(strings.ReplaceAll(step.Command, "-", "_"))
	switch cmd {
	case "version":
		return checkVersion(step, client)
	case "clients", "client_info":
		return checkClients(bench, step, client)
	case "deadzone", "accel_deadzone":
		return checkDeadzone(bench, step, client)
	case "unicast_test", "unicast":
		return checkUnicastTest(bench, step, client)
	default:
		return fmt.Errorf("unknown command %q", step.Command)
	}
}

func checkVersion(step Step, client MasterClient) error {
	ver, err := client.GetVersion()
	if err != nil {
		return err
	}
	e := step.Expect
	if e.Version != nil && ver.GetVersion() != *e.Version {
		return fmt.Errorf("version=%d want %d", ver.GetVersion(), *e.Version)
	}
	if e.VersionMin != nil && ver.GetVersion() < *e.VersionMin {
		return fmt.Errorf("version=%d want >= %d", ver.GetVersion(), *e.VersionMin)
	}
	if e.GitHash != "" && ver.GetGitHash() != e.GitHash {
		return fmt.Errorf("git_hash=%q want %q", ver.GetGitHash(), e.GitHash)
	}
	return nil
}

func checkClients(bench *Bench, step Step, client MasterClient) error {
	clients, err := client.ListClients()
	if err != nil {
		return err
	}
	e := step.Expect
	n := len(clients)

	if e.ClientCount != nil && n != *e.ClientCount {
		return fmt.Errorf("client_count=%d want %d", n, *e.ClientCount)
	}
	if e.MinClients != nil && n < *e.MinClients {
		return fmt.Errorf("client_count=%d want >= %d", n, *e.MinClients)
	}
	if e.MaxClients != nil && n > *e.MaxClients {
		return fmt.Errorf("client_count=%d want <= %d", n, *e.MaxClients)
	}

	slaveNames := e.Slaves
	if e.Slave != "" {
		slaveNames = append(slaveNames, e.Slave)
	}
	for _, name := range slaveNames {
		want, err := bench.Slave(name)
		if err != nil {
			return err
		}
		var found *pb.ClientInfo
		for _, c := range clients {
			if MACEqual(MACFromProto(c.GetMac()), want.MAC) {
				found = c
				break
			}
		}
		if found == nil {
			return fmt.Errorf("slave %q mac %s not in client list", name, want.MAC)
		}
		if uint32(*want.ClientID) != found.GetId() {
			return fmt.Errorf("slave %q id=%d want client_id=%d", name, found.GetId(), *want.ClientID)
		}
		if e.Available != nil && found.GetAvailable() != *e.Available {
			return fmt.Errorf("slave %q available=%v want %v", name, found.GetAvailable(), *e.Available)
		}
		if e.MAC != "" && !MACEqual(MACFromProto(found.GetMac()), e.MAC) {
			return fmt.Errorf("slave %q mac=%s want %s", name, MACFromProto(found.GetMac()), e.MAC)
		}
	}
	return nil
}

type deadzoneInput struct {
	Write      bool   `json:"write"`
	Value      uint   `json:"value"`
	Deadzone   uint   `json:"deadzone"`
	ClientID   *uint  `json:"client_id"`
	Client     uint   `json:"client"`
	Slave      string `json:"slave"`
	AllClients bool   `json:"all_clients"`
}

func checkDeadzone(bench *Bench, step Step, client MasterClient) error {
	var in deadzoneInput
	if len(step.Input) > 0 {
		if err := json.Unmarshal(step.Input, &in); err != nil {
			return fmt.Errorf("input: %w", err)
		}
	}
	dz := in.Value
	if dz == 0 {
		dz = in.Deadzone
	}

	var clientID uint32
	switch {
	case in.AllClients:
		// client_id 0 with all_clients set
	case in.Slave != "":
		id, err := bench.ResolveClientID(in.Slave)
		if err != nil {
			return err
		}
		clientID = id
	case in.ClientID != nil:
		clientID = uint32(*in.ClientID)
	default:
		clientID = uint32(in.Client)
	}

	req := &pb.AccelDeadzoneRequest{
		Write:       in.Write,
		Deadzone:    uint32(dz),
		ClientId:    clientID,
		AllClients:  in.AllClients,
	}
	resp, err := client.AccelDeadzone(req)
	if err != nil {
		return err
	}

	e := step.Expect
	if e.Deadzone != nil && resp.GetDeadzone() != *e.Deadzone {
		return fmt.Errorf("deadzone=%d want %d", resp.GetDeadzone(), *e.Deadzone)
	}
	if e.Success != nil && resp.GetSuccess() != *e.Success {
		return fmt.Errorf("success=%v want %v", resp.GetSuccess(), *e.Success)
	}
	if e.SlavesUpdated != nil && resp.GetSlavesUpdated() != *e.SlavesUpdated {
		return fmt.Errorf("slaves_updated=%d want %d", resp.GetSlavesUpdated(), *e.SlavesUpdated)
	}
	if e.SlavesUpdatedMin != nil && resp.GetSlavesUpdated() < *e.SlavesUpdatedMin {
		return fmt.Errorf("slaves_updated=%d want >= %d", resp.GetSlavesUpdated(), *e.SlavesUpdatedMin)
	}
	return nil
}

type unicastInput struct {
	Seq      uint   `json:"seq"`
	ClientID *uint  `json:"client_id"`
	Client   uint   `json:"client"`
	Slave    string `json:"slave"`
}

func checkUnicastTest(bench *Bench, step Step, client MasterClient) error {
	var in unicastInput
	if len(step.Input) > 0 {
		if err := json.Unmarshal(step.Input, &in); err != nil {
			return fmt.Errorf("input: %w", err)
		}
	}
	if in.Seq == 0 {
		in.Seq = 1
	}

	var clientID uint32
	switch {
	case in.Slave != "":
		id, err := bench.ResolveClientID(in.Slave)
		if err != nil {
			return err
		}
		clientID = id
	case in.ClientID != nil:
		clientID = uint32(*in.ClientID)
	default:
		clientID = uint32(in.Client)
	}
	if clientID == 0 {
		return fmt.Errorf("unicast_test: client_id or slave required")
	}

	resp, err := client.EspnowUnicastTest(clientID, uint32(in.Seq))
	if err != nil {
		return err
	}

	e := step.Expect
	if e.Success != nil && resp.GetSuccess() != *e.Success {
		return fmt.Errorf("success=%v want %v", resp.GetSuccess(), *e.Success)
	}
	if e.Seq != nil && resp.GetSeq() != *e.Seq {
		return fmt.Errorf("seq=%d want %d", resp.GetSeq(), *e.Seq)
	}
	return nil
}