package dashboard

import (
	"fmt"
	"math"
	"net/http"
	"strconv"
	"strings"
)

type settingsPageData struct {
	PageData
	Settings orchestratorSettingsDTO
	Inbound  inboundChecksDTO
	// AutoCycle is the automatic-check-cycle panel's status/parameters.
	AutoCycle autoCycleDTO
}

func (s *Server) handleSettingsPage(w http.ResponseWriter, r *http.Request) {
	settings, err := s.CA.GetOrchestratorSettings(r.Context())
	inbound, inboundErr := s.CA.GetInboundChecks(r.Context())
	if err == nil {
		err = inboundErr
	}
	autoCycle, autoCycleErr := s.CA.GetAutoCycle(r.Context())
	if err == nil {
		err = autoCycleErr
	}
	data := settingsPageData{Settings: settings, Inbound: inbound, AutoCycle: autoCycle}
	data.ActiveNav = "settings"
	data.Banner = bannerFor(err)
	s.renderPage(w, "settings_page", data)
}

// renderSettingsForm re-fetches the current settings and renders the
// settings_form fragment, tagging actionErr (if any) on the shared error
// banner — same pattern as renderIPsTable: always reflect true current
// state regardless of whether the mutation itself succeeded.
func (s *Server) renderSettingsForm(w http.ResponseWriter, r *http.Request, actionErr error) {
	settings, getErr := s.CA.GetOrchestratorSettings(r.Context())
	if actionErr == nil {
		actionErr = getErr
	}
	inbound, inboundErr := s.CA.GetInboundChecks(r.Context())
	if actionErr == nil {
		actionErr = inboundErr
	}
	autoCycle, autoCycleErr := s.CA.GetAutoCycle(r.Context())
	if actionErr == nil {
		actionErr = autoCycleErr
	}
	s.renderFragment(w, "settings_form", settingsPageData{Settings: settings, Inbound: inbound, AutoCycle: autoCycle}, actionErr)
}

func (s *Server) handleSettingsPut(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		s.renderSettingsForm(w, r, fmt.Errorf("invalid form: %w", err))
		return
	}
	seconds, err := strconv.Atoi(r.PostFormValue("fip_settle_seconds"))
	if err != nil {
		s.renderSettingsForm(w, r, &apiErr{Status: http.StatusBadRequest, Message: "пауза должна быть целым числом секунд"})
		return
	}
	retentionCycles, err := strconv.Atoi(r.PostFormValue("history_retention_cycles"))
	if err != nil {
		s.renderSettingsForm(w, r, &apiErr{Status: http.StatusBadRequest, Message: "глубина истории должна быть целым числом циклов"})
		return
	}
	_, err = s.CA.PutOrchestratorSettings(r.Context(), seconds, retentionCycles)
	s.renderSettingsForm(w, r, err)
}

// handleInboundChecksPut parses the comma-separated ports field of the
// second form on /settings and saves it via PUT
// /api/v1/admin/config/inbound-checks. A separate form/handler from
// fip_settle_seconds above — the two settings are unrelated and shouldn't
// share one submit.
func (s *Server) handleInboundChecksPut(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		s.renderSettingsForm(w, r, fmt.Errorf("invalid form: %w", err))
		return
	}
	raw := strings.TrimSpace(r.PostFormValue("ports"))
	var ports []int
	if raw != "" {
		for _, part := range strings.Split(raw, ",") {
			part = strings.TrimSpace(part)
			if part == "" {
				continue
			}
			p, err := strconv.Atoi(part)
			if err != nil {
				s.renderSettingsForm(w, r, &apiErr{Status: http.StatusBadRequest, Message: "порты должны быть целыми числами через запятую"})
				return
			}
			ports = append(ports, p)
		}
	}
	icmp := r.PostFormValue("icmp") == "on"
	_, err := s.CA.PutInboundChecks(r.Context(), ports, icmp)
	s.renderSettingsForm(w, r, err)
}

// parseMinutes converts a form field holding a (possibly fractional) number
// of minutes into whole seconds.
func parseMinutes(raw string) (int, error) {
	f, err := strconv.ParseFloat(strings.TrimSpace(strings.ReplaceAll(raw, ",", ".")), 64)
	if err != nil || math.IsNaN(f) || math.IsInf(f, 0) || math.Abs(f) > 1e6 {
		return 0, fmt.Errorf("not a number of minutes: %q", raw)
	}
	return int(math.Round(f * 60)), nil
}

// handleAutoCyclePut saves the auto-cycle interval and maximum run duration
// (entered in minutes, sent to control-api in seconds). It does not touch
// the enabled flag — that's what the start/stop buttons are for.
func (s *Server) handleAutoCyclePut(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		s.renderSettingsForm(w, r, fmt.Errorf("invalid form: %w", err))
		return
	}
	intervalSec, err := parseMinutes(r.PostFormValue("interval_minutes"))
	if err != nil {
		s.renderSettingsForm(w, r, &apiErr{Status: http.StatusBadRequest, Message: "интервал должен быть числом минут"})
		return
	}
	maxRunSec, err := parseMinutes(r.PostFormValue("max_run_minutes"))
	if err != nil {
		s.renderSettingsForm(w, r, &apiErr{Status: http.StatusBadRequest, Message: "максимальная длительность должна быть числом минут (0 — без лимита)"})
		return
	}
	_, err = s.CA.PutAutoCycle(r.Context(), intervalSec, maxRunSec)
	s.renderSettingsForm(w, r, err)
}

func (s *Server) handleAutoCycleStart(w http.ResponseWriter, r *http.Request) {
	_, err := s.CA.StartAutoCycle(r.Context())
	s.renderSettingsForm(w, r, err)
}

func (s *Server) handleAutoCycleStop(w http.ResponseWriter, r *http.Request) {
	_, err := s.CA.StopAutoCycle(r.Context())
	s.renderSettingsForm(w, r, err)
}