package onboarding

import (
	"data-terminal-cloud/internal/deviceauth"
	"encoding/json"
	"net/http"
	"regexp"
	"strings"
)

var runtimePath = regexp.MustCompile(`^/device/v(?:2/conversations|3/agent-sessions)/([0-9a-f-]{36})(?:/(events|heartbeat|stop|activate|turns:batch|upload-batches))?$`)

func (s *Service) runtimeAdmission(r *http.Request, d Device, raw []byte) (bool, error) {
	create := r.URL.Path == "/device/v3/agent-sessions"
	match := runtimePath.FindStringSubmatch(r.URL.Path)
	if r.URL.Path == "/device/v2/conversations" {
		return false, deviceauth.ErrDeviceInactive
	}
	if len(match) > 0 {
		var current bool
		err := s.pool.QueryRow(r.Context(), `SELECT EXISTS(SELECT 1 FROM conversation WHERE public_id=$1::uuid AND device_id=$2::uuid AND onboarding_generation=$3)`, match[1], d.ID, d.Generation).Scan(&current)
		if err != nil {
			return false, err
		}
		if !current {
			return false, deviceauth.ErrDeviceInactive
		}
	}
	if !create && len(match) == 0 {
		parts := strings.Split(r.URL.Path, "/")
		if len(parts) >= 5 && (parts[3] == "upload-batches" || parts[3] == "media-segments") {
			if !uuidValid(parts[4]) {
				return false, deviceauth.ErrCredentialInvalid
			}
			table := "upload_batch"
			if parts[3] == "media-segments" {
				table = "media_segment"
			}
			var current bool
			err := s.pool.QueryRow(r.Context(), `SELECT EXISTS(SELECT 1 FROM `+table+` m JOIN conversation c ON c.id=m.conversation_id WHERE m.public_id=$1::uuid AND c.device_id=$2::uuid AND c.onboarding_generation=$3)`, parts[4], d.ID, d.Generation).Scan(&current)
			if err != nil {
				return false, err
			}
			if !current {
				return false, deviceauth.ErrDeviceInactive
			}
		}
		return false, nil
	}
	var intent, activation, attempt, token string
	if create {
		var input struct {
			Intent     string `json:"intent"`
			Activation string `json:"activation_id"`
			Attempt    string `json:"attempt_id"`
			Token      string `json:"permit_token"`
		}
		if err := json.Unmarshal(raw, &input); err != nil {
			return false, deviceauth.ErrCredentialInvalid
		}
		intent = input.Intent
		activation = input.Activation
		attempt = input.Attempt
		token = input.Token
	}
	var ready bool
	err := s.pool.QueryRow(r.Context(), `SELECT EXISTS(SELECT 1 FROM device_activation_job j JOIN device_binding b ON b.device_id=j.device_id AND b.generation=j.binding_generation AND b.unbound_at IS NULL WHERE j.device_id=$1::uuid AND j.binding_generation=$2 AND j.status='READY' AND j.config_ack_at IS NOT NULL AND j.config_expires_at>now())`, d.ID, d.Generation).Scan(&ready)
	if err != nil {
		return false, err
	}
	if ready && intent != "activation_test" {
		return false, nil
	}
	var valid bool
	if create {
		if intent != "activation_test" || !uuidV4(activation) || !uuidV4(attempt) || (token != "" && !validB64(token, 32)) {
			return false, deviceauth.ErrDeviceInactive
		}
		err = s.pool.QueryRow(r.Context(), `SELECT EXISTS(SELECT 1 FROM device_activation_job j JOIN device_activation_attempt a ON a.activation_id=j.id JOIN device_binding b ON b.device_id=j.device_id AND b.generation=j.binding_generation AND b.unbound_at IS NULL WHERE j.device_id=$1::uuid AND j.id=$2::uuid AND a.id=$3::uuid AND j.binding_generation=$4 AND a.binding_generation=$4 AND a.config_version=j.config_version AND j.status IN ('REGISTERED_OBSERVED','CONTACT_POSSIBLE','READY') AND j.config_ack_at IS NOT NULL AND j.engine_ready_at IS NOT NULL AND j.config_expires_at>now() AND a.stage='CONVERSATION_TEST' AND a.executor='DEVICE' AND a.status='CONTACT_POSSIBLE' AND (a.permit_hash IS NULL OR a.permit_hash=$5) AND (a.permit_expires_at>now() OR a.conversation_id IS NOT NULL))`, d.ID, activation, attempt, d.Generation, digest([]byte(token))).Scan(&valid)
	} else {
		if len(match) > 2 && !oneOf(match[2], "", "events", "heartbeat", "stop") {
			return false, deviceauth.ErrDeviceInactive
		}
		err = s.pool.QueryRow(r.Context(), `SELECT EXISTS(SELECT 1 FROM conversation c JOIN device_activation_attempt a ON a.conversation_id=c.id JOIN device_activation_job j ON j.id=a.activation_id WHERE c.public_id=$1::uuid AND c.device_id=$2::uuid AND j.binding_generation=$3 AND a.binding_generation=$3 AND a.config_version=j.config_version AND a.stage='CONVERSATION_TEST' AND a.status IN ('CONTACT_POSSIBLE','SUCCESS_OBSERVED','UNKNOWN'))`, match[1], d.ID, d.Generation).Scan(&valid)
	}
	if err != nil {
		return false, err
	}
	if !valid {
		return false, deviceauth.ErrDeviceInactive
	}
	return true, nil
}