package httpapi

import (
	"net/http"
	"regexp"
	"strings"

	"data-terminal-cloud/internal/deviceauth"
	"data-terminal-cloud/internal/saas"
)

var sha256Pattern = regexp.MustCompile(`^[0-9a-f]{64}$`)

func RegisterFirmwareSigningKeyHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		var in struct {
			KeyID     string `json:"key_id"`
			PublicKey string `json:"public_key_base64"`
		}
		if !decodeWebJSON(w, r, &in, "固件签名密钥参数不正确") {
			return
		}
		in.KeyID = strings.TrimSpace(in.KeyID)
		in.PublicKey = strings.TrimSpace(in.PublicKey)
		if in.KeyID == "" || in.PublicKey == "" {
			writeValidation(w, r, "固件签名密钥参数不正确", FieldError{Field: "key", Message: "密钥编号和Ed25519公钥均为必填"})
			return
		}
		if err := service.RegisterFirmwareSigningKey(r.Context(), p, r.PathValue("id"), RequestID(r.Context()), in.KeyID, in.PublicKey); err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusCreated, map[string]any{"key_id": in.KeyID, "status": "ACTIVE"})
	})
}

func ListFirmwareSigningKeysHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		items, err := service.ListFirmwareSigningKeys(r.Context(), p, r.PathValue("id"))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, map[string]any{"items": items})
	})
}

func RevokeFirmwareSigningKeyHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		var input struct {
			KeyID string `json:"key_id"`
		}
		if !decodeWebJSON(w, r, &input, "固件签名密钥吊销参数不正确") {
			return
		}
		input.KeyID = strings.TrimSpace(input.KeyID)
		if input.KeyID == "" || len([]rune(input.KeyID)) > 120 {
			writeValidation(w, r, "固件签名密钥吊销参数不正确", FieldError{Field: "key_id", Message: "密钥编号必须为1至120个字符"})
			return
		}
		item, err := service.RevokeFirmwareSigningKey(r.Context(), p, r.PathValue("id"), RequestID(r.Context()), input.KeyID)
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, item)
	})
}

func PrepareFirmwareReleaseHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		var in struct {
			Model                  string `json:"model"`
			HardwareRevision       string `json:"hardware_revision"`
			Version                string `json:"version"`
			ExpectedSize           int64  `json:"expected_size"`
			ExpectedDigest         string `json:"expected_digest"`
			Signature              string `json:"signature"`
			SigningKeyID           string `json:"signing_key_id"`
			MinimumSecurityVersion string `json:"minimum_security_version"`
			ReleaseNotes           string `json:"release_notes"`
		}
		if !decodeWebJSON(w, r, &in, "固件版本参数不正确") {
			return
		}
		in.Model = strings.TrimSpace(in.Model)
		in.HardwareRevision = strings.TrimSpace(in.HardwareRevision)
		in.Version = strings.TrimSpace(in.Version)
		in.ExpectedDigest = strings.ToLower(strings.TrimSpace(in.ExpectedDigest))
		in.Signature = strings.TrimSpace(in.Signature)
		in.SigningKeyID = strings.TrimSpace(in.SigningKeyID)
		if in.Model == "" || in.Version == "" || in.ExpectedSize < 1 || in.ExpectedSize > 268435456 || !sha256Pattern.MatchString(in.ExpectedDigest) || in.Signature == "" || in.SigningKeyID == "" {
			writeValidation(w, r, "固件版本参数不正确", FieldError{Field: "firmware", Message: "型号、版本、1至256MB大小、SHA-256、Ed25519签名和密钥编号均为必填"})
			return
		}
		item, err := service.PrepareFirmwareRelease(r.Context(), p, r.PathValue("id"), RequestID(r.Context()), saas.PrepareFirmwareInput{Model: in.Model, HardwareRevision: in.HardwareRevision, Version: in.Version, ExpectedSize: in.ExpectedSize, ExpectedDigest: in.ExpectedDigest, Signature: in.Signature, SigningKeyID: in.SigningKeyID, MinimumSecurityVersion: strings.TrimSpace(in.MinimumSecurityVersion), ReleaseNotes: strings.TrimSpace(in.ReleaseNotes)})
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		w.Header().Set("Cache-Control", "no-store")
		WriteJSON(w, r, http.StatusCreated, item)
	})
}

func ListFirmwareReleasesHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		items, err := service.ListFirmwareReleases(r.Context(), p, r.PathValue("id"))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, map[string]any{"items": items})
	})
}

func GetFirmwareReleaseImpactHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		item, err := service.GetFirmwareReleaseImpact(r.Context(), p, r.PathValue("id"))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, item)
	})
}

func FinalizeFirmwareReleaseHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		item, err := service.FinalizeFirmwareRelease(r.Context(), p, r.PathValue("id"), RequestID(r.Context()))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, item)
	})
}

func RenewFirmwareUploadHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		item, err := service.RenewFirmwareUpload(r.Context(), p, r.PathValue("id"), RequestID(r.Context()))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		w.Header().Set("Cache-Control", "no-store")
		WriteJSON(w, r, http.StatusOK, item)
	})
}

func PauseFirmwareReleaseHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		item, err := service.PauseFirmwareRelease(r.Context(), p, r.PathValue("id"), RequestID(r.Context()))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, item)
	})
}

func ResumeFirmwareReleaseHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		item, err := service.ResumeFirmwareRelease(r.Context(), p, r.PathValue("id"), RequestID(r.Context()))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, item)
	})
}

func RetireFirmwareReleaseHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		item, err := service.RetireFirmwareRelease(r.Context(), p, r.PathValue("id"), RequestID(r.Context()))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, item)
	})
}

func StartFirmwareRolloutHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		var in struct {
			ReleaseID        string   `json:"release_id"`
			Name             string   `json:"name"`
			TargetPercentage int      `json:"target_percentage"`
			DeviceIDs        []string `json:"device_ids"`
		}
		if !decodeWebJSON(w, r, &in, "固件灰度批次参数不正确") {
			return
		}
		in.ReleaseID = strings.TrimSpace(in.ReleaseID)
		in.Name = strings.TrimSpace(in.Name)
		if in.ReleaseID == "" || in.Name == "" || in.TargetPercentage < 1 || in.TargetPercentage > 100 || len(in.DeviceIDs) == 0 {
			writeValidation(w, r, "固件灰度批次参数不正确", FieldError{Field: "rollout", Message: "版本、批次名称、1至100灰度比例和目标设备均为必填"})
			return
		}
		item, err := service.StartFirmwareRollout(r.Context(), p, r.PathValue("id"), in.ReleaseID, RequestID(r.Context()), in.Name, in.TargetPercentage, in.DeviceIDs)
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusAccepted, item)
	})
}

func ListFirmwareRolloutsHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		items, err := service.ListFirmwareRollouts(r.Context(), p, r.PathValue("id"))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, map[string]any{"items": items})
	})
}

func DeviceFirmwareDownloadHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		id, ok := deviceauth.FromContext(r.Context())
		if !ok {
			WriteError(w, r, http.StatusUnauthorized, "DEVICE_AUTHENTICATION_FAILED", "设备身份验证失败")
			return
		}
		url, until, err := service.FirmwareDownloadForDevice(r.Context(), id, r.PathValue("id"))
		if err != nil {
			WriteError(w, r, http.StatusForbidden, "FIRMWARE_DOWNLOAD_DENIED", "设备不在该固件批次中或版本不可下载")
			return
		}
		w.Header().Set("Cache-Control", "no-store")
		WriteJSON(w, r, http.StatusOK, map[string]any{"download_url": url, "download_until": until})
	})
}

func GetFirmwareRolloutHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		item, err := service.GetFirmwareRollout(r.Context(), p, r.PathValue("id"))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, item)
	})
}
func PauseFirmwareRolloutHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		item, err := service.PauseFirmwareRollout(r.Context(), p, r.PathValue("id"), RequestID(r.Context()))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusOK, item)
	})
}
func RollbackFirmwareRolloutHandler(service *saas.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p, ok := resourcePrincipal(w, r, "id")
		if !ok {
			return
		}
		var in struct {
			ReleaseID string `json:"rollback_release_id"`
		}
		if !decodeWebJSON(w, r, &in, "固件回滚参数不正确") {
			return
		}
		in.ReleaseID = strings.TrimSpace(in.ReleaseID)
		if in.ReleaseID == "" {
			writeValidation(w, r, "固件回滚参数不正确", FieldError{Field: "rollback_release_id", Message: "必须选择已验证的回滚版本"})
			return
		}
		item, err := service.StartFirmwareRollback(r.Context(), p, r.PathValue("id"), in.ReleaseID, RequestID(r.Context()))
		if err != nil {
			writeSaaSError(w, r, err)
			return
		}
		WriteJSON(w, r, http.StatusAccepted, item)
	})
}