package api

// Outgoing-webhook signing-secret + send-test endpoints. There are four
// tiers — settings, project, stage, site — each exposing the same three
// operations: reveal (lazy-gen), regenerate, and send a synthetic test
// event. Returning a 200 from "send test" doesn't mean the receiver
// processed the event correctly — only that it answered with 2xx. The UI
// surfaces the receiver's status code + body preview so operators can
// distinguish "wired" from "wired and accepted".

import (
	"context"
	"errors"
	"log/slog"
	"net/http"
	"time"

	"github.com/go-chi/chi/v5"

	"github.com/alexei/tinyforge/internal/notify"
	"github.com/alexei/tinyforge/internal/store"
)

// notificationSecretResponse is what the GET / regenerate endpoints return.
// The secret is revealed in cleartext exactly once per request — UI is
// expected to copy or hash it for display, not store it long-term.
type notificationSecretResponse struct {
	Secret    string `json:"secret"`
	HasSecret bool   `json:"has_secret"`
}

// testEventTimeout caps how long we wait for the receiver before declaring
// the test failed. Mirrors the production notifier's per-request timeout
// (10s) so test results are predictive of real send behaviour.
const testEventTimeout = 10 * time.Second

// buildTestEvent constructs the synthetic payload used by every "send
// test" endpoint. Marking it as type "test" prevents a misconfigured
// receiver from mistaking a wiring check for a real deploy event.
func buildTestEvent(project, stage string) notify.Event {
	return notify.Event{
		Type:    "test",
		Project: project,
		Stage:   stage,
	}
}

// ---------------------------------------------------------------------------
// Global / settings tier
// ---------------------------------------------------------------------------

// getSettingsNotificationSecret handles GET /api/settings/notification-secret.
// Lazily generates a secret if one was never set (typical for sites
// upgrading from a pre-signing build).
func (s *Server) getSettingsNotificationSecret(w http.ResponseWriter, r *http.Request) {
	secret, err := s.store.EnsureSettingsNotificationSecret()
	if err != nil {
		slog.Error("get settings notification secret", "error", err)
		respondError(w, http.StatusInternalServerError, "failed to load secret")
		return
	}
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: secret, HasSecret: secret != ""})
}

// regenerateSettingsNotificationSecret handles POST
// /api/settings/notification-secret/regenerate. Replaces the existing
// secret with a fresh one, invalidating signatures verified against the
// old secret.
func (s *Server) regenerateSettingsNotificationSecret(w http.ResponseWriter, r *http.Request) {
	secret := generateWebhookSecret()
	if err := s.store.SetSettingsNotificationSecret(secret); err != nil {
		slog.Error("regenerate settings notification secret", "error", err)
		respondError(w, http.StatusInternalServerError, "failed to rotate secret")
		return
	}
	slog.Info("settings notification secret rotated")
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: secret, HasSecret: true})
}

// disableSettingsNotificationSigning handles POST
// /api/settings/notification-secret/disable. Clears the secret so further
// outgoing notifications are unsigned. Useful for receivers that don't
// support HMAC verification.
func (s *Server) disableSettingsNotificationSigning(w http.ResponseWriter, r *http.Request) {
	if err := s.store.SetSettingsNotificationSecret(""); err != nil {
		slog.Error("disable settings notification signing", "error", err)
		respondError(w, http.StatusInternalServerError, "failed to disable signing")
		return
	}
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: "", HasSecret: false})
}

// settingsNotificationTest handles POST /api/settings/notification-test.
// Sends a synthetic test event to the global webhook URL using the global
// secret. No tier resolution — that's the whole point: each tier's test
// button proves *that* tier is wired correctly.
func (s *Server) settingsNotificationTest(w http.ResponseWriter, r *http.Request) {
	settings, err := s.store.GetSettings()
	if err != nil {
		respondError(w, http.StatusInternalServerError, "failed to load settings")
		return
	}
	if settings.NotificationURL == "" {
		respondError(w, http.StatusBadRequest, "no global notification URL configured")
		return
	}
	ctx, cancel := context.WithTimeout(r.Context(), testEventTimeout)
	defer cancel()
	result := s.notifier.SendSyncForTest(
		ctx, settings.NotificationURL, settings.NotificationSecret, notify.TierSettings,
		buildTestEvent("__tinyforge__", ""),
	)
	respondJSON(w, http.StatusOK, result)
}

// ---------------------------------------------------------------------------
// Project tier
// ---------------------------------------------------------------------------

func (s *Server) getProjectNotificationSecret(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	secret, err := s.store.EnsureProjectNotificationSecret(id)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "project")
			return
		}
		slog.Error("get project notification secret", "project", id, "error", err)
		respondError(w, http.StatusInternalServerError, "failed to load secret")
		return
	}
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: secret, HasSecret: secret != ""})
}

func (s *Server) regenerateProjectNotificationSecret(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if _, err := s.store.GetProjectByID(id); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "project")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to load project")
		return
	}
	secret := generateWebhookSecret()
	if err := s.store.SetProjectNotificationSecret(id, secret); err != nil {
		slog.Error("regenerate project notification secret", "project", id, "error", err)
		respondError(w, http.StatusInternalServerError, "failed to rotate secret")
		return
	}
	slog.Info("project notification secret rotated", "project", id)
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: secret, HasSecret: true})
}

func (s *Server) disableProjectNotificationSigning(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if err := s.store.SetProjectNotificationSecret(id, ""); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "project")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to disable signing")
		return
	}
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: "", HasSecret: false})
}

func (s *Server) projectNotificationTest(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	project, err := s.store.GetProjectByID(id)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "project")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to load project")
		return
	}
	settings, err := s.store.GetSettings()
	if err != nil {
		respondError(w, http.StatusInternalServerError, "failed to load settings")
		return
	}
	url, secret, tier := resolveProjectTestTarget(project, settings)
	if url == "" {
		respondError(w, http.StatusBadRequest, "no notification URL configured for this project (and no global fallback)")
		return
	}
	ctx, cancel := context.WithTimeout(r.Context(), testEventTimeout)
	defer cancel()
	result := s.notifier.SendSyncForTest(
		ctx, url, secret, tier,
		buildTestEvent(project.Name, ""),
	)
	respondJSON(w, http.StatusOK, result)
}

// resolveProjectTestTarget mirrors the deploy-time stage→project→global
// resolution but without a stage in scope. Used by the project-level test
// button so the operator sees exactly what a project-only event would do.
func resolveProjectTestTarget(project store.Project, settings store.Settings) (string, string, notify.Tier) {
	if project.NotificationURL != "" {
		return project.NotificationURL, project.NotificationSecret, notify.TierProject
	}
	return settings.NotificationURL, settings.NotificationSecret, notify.TierSettings
}

// ---------------------------------------------------------------------------
// Stage tier
// ---------------------------------------------------------------------------

func (s *Server) getStageNotificationSecret(w http.ResponseWriter, r *http.Request) {
	stageID := chi.URLParam(r, "stage")
	secret, err := s.store.EnsureStageNotificationSecret(stageID)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "stage")
			return
		}
		slog.Error("get stage notification secret", "stage", stageID, "error", err)
		respondError(w, http.StatusInternalServerError, "failed to load secret")
		return
	}
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: secret, HasSecret: secret != ""})
}

func (s *Server) regenerateStageNotificationSecret(w http.ResponseWriter, r *http.Request) {
	stageID := chi.URLParam(r, "stage")
	if _, err := s.store.GetStageByID(stageID); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "stage")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to load stage")
		return
	}
	secret := generateWebhookSecret()
	if err := s.store.SetStageNotificationSecret(stageID, secret); err != nil {
		slog.Error("regenerate stage notification secret", "stage", stageID, "error", err)
		respondError(w, http.StatusInternalServerError, "failed to rotate secret")
		return
	}
	slog.Info("stage notification secret rotated", "stage", stageID)
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: secret, HasSecret: true})
}

func (s *Server) disableStageNotificationSigning(w http.ResponseWriter, r *http.Request) {
	stageID := chi.URLParam(r, "stage")
	if err := s.store.SetStageNotificationSecret(stageID, ""); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "stage")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to disable signing")
		return
	}
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: "", HasSecret: false})
}

func (s *Server) stageNotificationTest(w http.ResponseWriter, r *http.Request) {
	projectID := chi.URLParam(r, "id")
	stageID := chi.URLParam(r, "stage")
	stage, err := s.store.GetStageByID(stageID)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "stage")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to load stage")
		return
	}
	project, err := s.store.GetProjectByID(projectID)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "project")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to load project")
		return
	}
	settings, err := s.store.GetSettings()
	if err != nil {
		respondError(w, http.StatusInternalServerError, "failed to load settings")
		return
	}
	// Reuse the production resolver so the test button exercises the exact
	// fall-through logic a real deploy would.
	url, secret, tier := resolveDeployTarget(stage, project, settings)
	if url == "" {
		respondError(w, http.StatusBadRequest, "no notification URL configured for this stage, project, or globally")
		return
	}
	ctx, cancel := context.WithTimeout(r.Context(), testEventTimeout)
	defer cancel()
	result := s.notifier.SendSyncForTest(
		ctx, url, secret, tier,
		buildTestEvent(project.Name, stage.Name),
	)
	respondJSON(w, http.StatusOK, result)
}

// resolveDeployTarget here mirrors the deployer's helper. Duplicated rather
// than imported to avoid an api → deployer dependency cycle and to keep the
// test-endpoint code self-contained. If divergence becomes a risk we can
// move this into a shared internal/notify subpackage.
func resolveDeployTarget(stage store.Stage, project store.Project, settings store.Settings) (string, string, notify.Tier) {
	if stage.NotificationURL != "" {
		return stage.NotificationURL, stage.NotificationSecret, notify.TierStage
	}
	if project.NotificationURL != "" {
		return project.NotificationURL, project.NotificationSecret, notify.TierProject
	}
	return settings.NotificationURL, settings.NotificationSecret, notify.TierSettings
}

// ---------------------------------------------------------------------------
// Static-site tier
// ---------------------------------------------------------------------------

func (s *Server) getStaticSiteNotificationSecret(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	secret, err := s.store.EnsureStaticSiteNotificationSecret(id)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "static site")
			return
		}
		slog.Error("get static site notification secret", "site", id, "error", err)
		respondError(w, http.StatusInternalServerError, "failed to load secret")
		return
	}
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: secret, HasSecret: secret != ""})
}

func (s *Server) regenerateStaticSiteNotificationSecret(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if _, err := s.store.GetStaticSiteByID(id); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "static site")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to load static site")
		return
	}
	secret := generateWebhookSecret()
	if err := s.store.SetStaticSiteNotificationSecret(id, secret); err != nil {
		slog.Error("regenerate static site notification secret", "site", id, "error", err)
		respondError(w, http.StatusInternalServerError, "failed to rotate secret")
		return
	}
	slog.Info("static site notification secret rotated", "site", id)
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: secret, HasSecret: true})
}

func (s *Server) disableStaticSiteNotificationSigning(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if err := s.store.SetStaticSiteNotificationSecret(id, ""); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "static site")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to disable signing")
		return
	}
	respondJSON(w, http.StatusOK, notificationSecretResponse{Secret: "", HasSecret: false})
}

func (s *Server) staticSiteNotificationTest(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	site, err := s.store.GetStaticSiteByID(id)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			respondNotFound(w, "static site")
			return
		}
		respondError(w, http.StatusInternalServerError, "failed to load static site")
		return
	}
	settings, err := s.store.GetSettings()
	if err != nil {
		respondError(w, http.StatusInternalServerError, "failed to load settings")
		return
	}
	url, secret, tier := resolveSiteTestTarget(site, settings)
	if url == "" {
		respondError(w, http.StatusBadRequest, "no notification URL configured for this site (and no global fallback)")
		return
	}
	ctx, cancel := context.WithTimeout(r.Context(), testEventTimeout)
	defer cancel()
	result := s.notifier.SendSyncForTest(
		ctx, url, secret, tier,
		buildTestEvent(site.Name, ""),
	)
	respondJSON(w, http.StatusOK, result)
}

func resolveSiteTestTarget(site store.StaticSite, settings store.Settings) (string, string, notify.Tier) {
	if site.NotificationURL != "" {
		return site.NotificationURL, site.NotificationSecret, notify.TierSite
	}
	return settings.NotificationURL, settings.NotificationSecret, notify.TierSettings
}