// Package checker probes a domain for the three competing email
// autoconfiguration mechanisms (Bucksch autoconfig, Microsoft Autodiscover
// POX, RFC 6186 SRV) and cross-checks them.
package checker

import (
	"time"
)

// ObservationKeyAutoconfig is the observation key for autoconfig data.
const ObservationKeyAutoconfig = "email_autoconfig"

// Data is the full collected payload.
type Data struct {
	Domain      string    `json:"domain"`
	Email       string    `json:"email"`
	CollectedAt time.Time `json:"collected_at"`

	MX      []MXRecord `json:"mx,omitempty"`
	MXError string     `json:"mx_error,omitempty"`

	SRV []SRVRecord `json:"srv,omitempty"`

	Autoconfig   []AutoconfigProbe   `json:"autoconfig,omitempty"`
	Autodiscover []AutodiscoverProbe `json:"autodiscover,omitempty"`

	// First successful autoconfig parse, promoted here for rules to consume.
	ClientConfig       *ClientConfig `json:"client_config,omitempty"`
	ClientConfigSource string        `json:"client_config_source,omitempty"`

	AutodiscoverResult *AutodiscoverResponse `json:"autodiscover_result,omitempty"`
}

// MXRecord is a single MX record.
type MXRecord struct {
	Host       string `json:"host"`
	Preference uint16 `json:"preference"`
}

// SRVRecord is a single RFC 6186 SRV record observation.
type SRVRecord struct {
	Service  string `json:"service"` // RFC 6186 tag, e.g. "_imaps._tcp"
	Target   string `json:"target"`
	Port     uint16 `json:"port"`
	Priority uint16 `json:"priority"`
	Weight   uint16 `json:"weight"`
	// Skip means the service is explicitly disabled (RFC 6186 target ".").
	Skip bool `json:"skip,omitempty"`
}

// ProbeResult captures the outcome of a single HTTP probe.
type ProbeResult struct {
	URL           string `json:"url"`
	Method        string `json:"method,omitempty"`
	StatusCode    int    `json:"status_code,omitempty"`
	DurationMs    int64  `json:"duration_ms,omitempty"`
	ContentType   string `json:"content_type,omitempty"`
	BodyBytes     int    `json:"body_bytes,omitempty"`
	Redirected    bool   `json:"redirected,omitempty"`
	FinalURL      string `json:"final_url,omitempty"`
	TLSServerName string `json:"tls_server_name,omitempty"`
	TLSIssuer     string `json:"tls_issuer,omitempty"`
	TLSSubject    string `json:"tls_subject,omitempty"`
	TLSNotAfter   string `json:"tls_not_after,omitempty"`
	TLSError      string `json:"tls_error,omitempty"`
	Error         string `json:"error,omitempty"`
	ParseError    string `json:"parse_error,omitempty"`
}

// AutoconfigProbe is one probe attempt for Thunderbird-style autoconfig.
type AutoconfigProbe struct {
	Source string        `json:"source"` // "autoconfig", "wellknown", "http-autoconfig", "ispdb", "mx-autoconfig", "mx-ispdb"
	Result ProbeResult   `json:"result"`
	Parsed *ClientConfig `json:"parsed,omitempty"`
}

// AutodiscoverProbe is one probe attempt for MS Autodiscover (POX).
type AutodiscoverProbe struct {
	Source string                `json:"source"` // "root", "subdomain", "srv", "redirect"
	Result ProbeResult           `json:"result"`
	Parsed *AutodiscoverResponse `json:"parsed,omitempty"`
}

// ClientConfig is the parsed Thunderbird-style clientConfig document.
type ClientConfig struct {
	Version         string          `json:"version,omitempty"`
	EmailProviderID string          `json:"email_provider_id,omitempty"`
	DisplayName     string          `json:"display_name,omitempty"`
	ShortName       string          `json:"short_name,omitempty"`
	Domains         []string        `json:"domains,omitempty"`
	Incoming        []ServerConfig  `json:"incoming,omitempty"`
	Outgoing        []ServerConfig  `json:"outgoing,omitempty"`
	AddressBook     []DavServer     `json:"address_book,omitempty"`
	Calendar        []DavServer     `json:"calendar,omitempty"`
	WebMail         *WebMail        `json:"webmail,omitempty"`
	Documentation   []Documentation `json:"documentation,omitempty"`
}

// ServerConfig is one incoming/outgoing server definition.
type ServerConfig struct {
	Type           string `json:"type"` // imap, pop3, smtp
	Hostname       string `json:"hostname"`
	Port           int    `json:"port"`
	SocketType     string `json:"socket_type"`    // plain, SSL, STARTTLS
	Username       string `json:"username"`       // may contain %EMAIL% placeholders
	Authentication string `json:"authentication"` // password-cleartext, password-encrypted, OAuth2, ...
}

// DavServer is a CardDAV or CalDAV server reference.
type DavServer struct {
	Type           string `json:"type"`
	Username       string `json:"username,omitempty"`
	Authentication string `json:"authentication,omitempty"`
	ServerURL      string `json:"server_url,omitempty"`
}

// WebMail holds webmail configuration (if any).
type WebMail struct {
	LoginPage string `json:"login_page,omitempty"`
}

// Documentation is a clientConfig <documentation> entry.
type Documentation struct {
	URL   string `json:"url,omitempty"`
	Descr string `json:"descr,omitempty"`
}

// AutodiscoverResponse is the parsed POX response.
type AutodiscoverResponse struct {
	DisplayName string `json:"display_name,omitempty"`
	// Set when Action is redirectAddr / redirectUrl; mutually exclusive with Protocols.
	RedirectAddr string                 `json:"redirect_addr,omitempty"`
	RedirectURL  string                 `json:"redirect_url,omitempty"`
	Protocols    []AutodiscoverProtocol `json:"protocols,omitempty"`
}

// AutodiscoverProtocol covers IMAP/POP/SMTP fields; Exchange-only protocols
// (EXCH/EXPR/MobileSync) are stored but not analysed.
type AutodiscoverProtocol struct {
	Type           string `json:"type"` // IMAP, POP3, SMTP, EXCH, EXPR, WEB, MobileSync
	Server         string `json:"server,omitempty"`
	Port           int    `json:"port,omitempty"`
	Encryption     string `json:"encryption,omitempty"` // SSL, TLS, None
	SSL            string `json:"ssl,omitempty"`        // on/off
	LoginName      string `json:"login_name,omitempty"`
	DomainRequired string `json:"domain_required,omitempty"`
	AuthRequired   string `json:"auth_required,omitempty"`
}