package report

import (
	"errors"
	"fmt"
	"io"
	"net/http"
	"strings"
	"time"
)

// Config-pull error types for setup-wizard UI display.
//
// These (and PullConfig) were previously part of infra_pull.go alongside the
// disk-tier DR-recovery (PullRecovery / infra-backup) client. Disk recovery moved
// to the host agent in slice 8C; only the fresh-install config download survives
// here, so it lives in this slimmed file.
var (
	ErrHubUnreachable = errors.New("hub unreachable")
	ErrAuthFailed     = errors.New("authentication failed")
	ErrNotFound       = errors.New("customer not found")
	ErrHubError       = errors.New("hub error")
)

// PullConfig fetches a generated controller.yaml from the Hub config endpoint.
// Auth: X-Retrieval-Password header. Used by the setup wizard's fresh-install flow.
func PullConfig(hubURL, customerID, retrievalPassword string) (string, error) {
	url := strings.TrimRight(hubURL, "/") + "/api/v1/config/" + customerID

	client := &http.Client{Timeout: 30 * time.Second}

	req, err := http.NewRequest(http.MethodGet, url, nil)
	if err != nil {
		return "", fmt.Errorf("%w: %v", ErrHubError, err)
	}
	req.Header.Set("X-Retrieval-Password", retrievalPassword)

	resp, err := client.Do(req)
	if err != nil {
		return "", fmt.Errorf("%w: %v", ErrHubUnreachable, err)
	}
	defer resp.Body.Close()

	switch resp.StatusCode {
	case http.StatusOK:
		// success
	case http.StatusUnauthorized:
		return "", ErrAuthFailed
	case http.StatusNotFound:
		return "", ErrNotFound
	default:
		return "", fmt.Errorf("%w: HTTP %d", ErrHubError, resp.StatusCode)
	}

	body, err := io.ReadAll(io.LimitReader(resp.Body, 1<<20)) // 1MB limit
	if err != nil {
		return "", fmt.Errorf("%w: reading response: %v", ErrHubError, err)
	}

	return string(body), nil
}

// ErrBoxConfigUnsupported: the hub has no GET /box-config (a hub before v0.161.0) — the caller falls back to the
// passphrase pull.
var ErrBoxConfigUnsupported = errors.New("hub has no box-config route")

// PullBoxConfig fetches the generated controller.yaml with the box's OWN hub key (GET /api/v1/box-config/{id}, hub ≥
// v0.161.0; R-1159). A live box refreshes its config this way, so the hub can refuse the household's retrieval
// passphrase once the box is live (hub `api/passphrase_scope.go`).
func PullBoxConfig(hubURL, customerID, apiKey string) (string, error) {
	url := strings.TrimRight(hubURL, "/") + "/api/v1/box-config/" + customerID
	client := &http.Client{Timeout: 30 * time.Second}
	req, err := http.NewRequest(http.MethodGet, url, nil)
	if err != nil {
		return "", fmt.Errorf("%w: %v", ErrHubError, err)
	}
	req.Header.Set("Authorization", "Bearer "+apiKey)
	resp, err := client.Do(req)
	if err != nil {
		return "", fmt.Errorf("%w: %v", ErrHubUnreachable, err)
	}
	defer resp.Body.Close()
	switch resp.StatusCode {
	case http.StatusOK:
	case http.StatusUnauthorized:
		return "", ErrAuthFailed
	case http.StatusNotFound, http.StatusMethodNotAllowed:
		return "", ErrBoxConfigUnsupported
	default:
		return "", fmt.Errorf("%w: HTTP %d", ErrHubError, resp.StatusCode)
	}
	body, err := io.ReadAll(io.LimitReader(resp.Body, 1<<20))
	if err != nil {
		return "", fmt.Errorf("%w: reading response: %v", ErrHubError, err)
	}
	return string(body), nil
}

// PullConfigPreferKey is the LIVE box's config refresh (report.ConfigRefresher): with the box's own key first; the
// retrieval passphrase only when the hub has no box-config route (a hub before v0.161.0) or the box holds no key yet.
// Any other answer to the key pull is returned as it is — never retried with the passphrase (R-1159: the passphrase
// is for a box that has no key of its own). Pinned by TestR1159_RefreshUsesTheBoxKey.
func PullConfigPreferKey(hubURL, customerID, apiKey, retrievalPassword string, logf func(string, ...any)) (string, error) {
	if apiKey != "" {
		y, err := PullBoxConfig(hubURL, customerID, apiKey)
		if !errors.Is(err, ErrBoxConfigUnsupported) {
			if err == nil {
				logf("[INFO] [config] refreshed controller.yaml with the box's own hub key (box-config)")
			}
			return y, err
		}
		logf("[INFO] [config] the hub has no box-config route (hub < 0.161.0) — refreshing with the retrieval passphrase")
	}
	return PullConfig(hubURL, customerID, retrievalPassword)
}