package main

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

type bleRttAPIRequest struct {
	Count   *int     `json:"count"`
	Warmup  *int     `json:"warmup"`
	SettleS *float64 `json:"settle_s"`
}

type bleStreamAPIRequest struct {
	ClientID *uint32  `json:"client_id"`
	PeriodMs *uint32  `json:"period_ms"`
	Count    *int     `json:"count"`
	TolMs    *float64 `json:"tol_ms"`
	TimeoutS *float64 `json:"timeout_s"`
}

func mountBleTestAPI(mux *http.ServeMux, link *managedHost) {
	mux.HandleFunc("/api/ble-rtt", func(w http.ResponseWriter, r *http.Request) {
		if r.Method != http.MethodPost {
			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
			return
		}
		serveBleRtt(w, r, link)
	})
	mux.HandleFunc("/api/ble-stream", func(w http.ResponseWriter, r *http.Request) {
		if r.Method != http.MethodPost {
			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
			return
		}
		serveBleStreamTest(w, r, link)
	})
}

func requireBLEHost(w http.ResponseWriter, link *managedHost) bool {
	if link.Transport() != hostTransportBLE || !link.IsConnected() {
		writeJSON(w, http.StatusBadRequest, bleRttResult{
			Error: "BLE host required (connect via BLE, DIP8=1)",
		})
		return false
	}
	return true
}

func serveBleRtt(w http.ResponseWriter, r *http.Request, link *managedHost) {
	if !requireBLEHost(w, link) {
		return
	}
	var body bleRttAPIRequest
	if err := json.NewDecoder(r.Body).Decode(&body); err != nil && !errors.Is(err, io.EOF) {
		writeJSON(w, http.StatusBadRequest, bleRttResult{Error: "invalid JSON"})
		return
	}
	count, warmup := 50, 5
	settle := 0.0
	if body.Count != nil {
		count = *body.Count
	}
	if body.Warmup != nil {
		warmup = *body.Warmup
	}
	if body.SettleS != nil {
		settle = *body.SettleS
	}

	if !link.beginPausePoll() {
		writeJSON(w, http.StatusConflict, bleRttResult{Error: "host busy"})
		return
	}
	defer link.endPausePoll()

	out := measureBleRtt(link, count, warmup, time.Duration(settle*float64(time.Second)))
	status := http.StatusOK
	if !out.Success {
		status = http.StatusBadRequest
	}
	writeJSON(w, status, out)
}

func serveBleStreamTest(w http.ResponseWriter, r *http.Request, link *managedHost) {
	if !requireBLEHost(w, link) {
		return
	}
	var body bleStreamAPIRequest
	if err := json.NewDecoder(r.Body).Decode(&body); err != nil && !errors.Is(err, io.EOF) {
		writeJSON(w, http.StatusBadRequest, bleStreamResult{Error: "invalid JSON"})
		return
	}
	count := 50
	periodMs := uint32(16)
	tolMs := 2.0
	timeoutS := 15.0
	var clientID uint32
	if body.Count != nil {
		count = *body.Count
	}
	if body.PeriodMs != nil {
		periodMs = *body.PeriodMs
	}
	if body.TolMs != nil {
		tolMs = *body.TolMs
	}
	if body.TimeoutS != nil {
		timeoutS = *body.TimeoutS
	}
	if body.ClientID != nil {
		clientID = *body.ClientID
	}

	if !link.beginPausePoll() {
		writeJSON(w, http.StatusConflict, bleStreamResult{Error: "host busy"})
		return
	}
	defer link.endPausePoll()

	out := measureBleStream(link, clientID, periodMs, count, tolMs, timeoutS)
	status := http.StatusOK
	if !out.Success {
		status = http.StatusBadRequest
	}
	writeJSON(w, status, out)
}