package saas

import (
	"context"
	"crypto/sha256"
	"encoding/hex"
	"errors"
	"fmt"

	"data-terminal-cloud/internal/audit"
	"github.com/jackc/pgx/v5"
)

type InitialConsentSelection struct {
	Types     []string `json:"types"`
	Confirmed bool     `json:"confirmed"`
}

var ErrInitialConsentInvalid = errors.New("initial consent selection is invalid or unconfirmed")

var initialConsentNotices = map[string]string{
	ConsentTranscriptStorage: "保存后续聊天的文字记录，便于查看聊天内容。",
	ConsentRawAudioStorage:   "保存后续聊天的原始录音；播放、下载仍需单独权限，设备支持录音上传时才能生成录音。",
	ConsentStoryExtraction:   "从后续聊天文字整理故事和摘要，需要同时开启字幕保存。",
	ConsentPersonalMemory:    "从后续聊天文字整理名字、偏好等记忆，并用于下次聊天；生成新记忆需要同时开启字幕保存。",
	ConsentFamilySharing:     "允许按后续独立分享规则向家庭成员分享内容；本项不会自动分享全部聊天或录音。",
}

func ValidateInitialConsents(selection InitialConsentSelection) error {
	if len(selection.Types) > 0 && !selection.Confirmed {
		return ErrInitialConsentInvalid
	}
	seen := map[string]bool{}
	for _, kind := range selection.Types {
		if _, ok := initialConsentNotices[kind]; !ok || seen[kind] {
			return ErrInitialConsentInvalid
		}
		seen[kind] = true
	}
	return nil
}

// InitializeSubjectMemory is called only from new-profile creation, never from
// binding, profile edits, or reads, so a withdrawn permission stays withdrawn.
func InitializeSubjectMemory(ctx context.Context, tx pgx.Tx, tenantID, subjectPublicID, actorID, requestID string, selection InitialConsentSelection) error {
	if err := ValidateInitialConsents(selection); err != nil {
		return err
	}
	var subjectID, policy, actorPublicID string
	if err := tx.QueryRow(ctx, `SELECT sp.id::text,t.policy_version,ua.public_id::text
 FROM subject_profile sp JOIN tenant t ON t.id=sp.tenant_id
 JOIN user_account ua ON ua.tenant_id=t.id AND ua.id=$3::uuid
 WHERE sp.public_id=$1::uuid AND sp.tenant_id=$2::uuid AND ua.status='active'
 FOR UPDATE OF sp`, subjectPublicID, tenantID, actorID).Scan(&subjectID, &policy, &actorPublicID); err != nil {
		return fmt.Errorf("resolve initial memory consent: %w", err)
	}
	for _, kind := range selection.Types {
		sum := sha256.Sum256([]byte(initialConsentNotices[kind] + "各项授权适用于后续新通话，可在数据与授权中分别撤回。"))
		var consentID string
		if err := tx.QueryRow(ctx, `INSERT INTO consent_record
 (tenant_id,subject_id,consent_type,scope,policy_version,notice_digest,actor_user_id,evidence_ref)
 VALUES($1::uuid,$2::uuid,$3,'{"scope":"future_conversations","source":"subject_creation_selection","notice_version":"creation-consents-v1"}'::jsonb,$4,$5,$6::uuid,$7)
 RETURNING public_id::text`, tenantID, subjectID, kind, policy, hex.EncodeToString(sum[:]), actorID, "subject-create:"+requestID).Scan(&consentID); err != nil {
			return fmt.Errorf("insert initial memory consent: %w", err)
		}
		if err := audit.NewRepository().Record(ctx, tx, audit.Event{
			TenantID: &tenantID, ActorType: "user", ActorPublicID: &actorPublicID,
			Action: "consent.grant", ResourceType: "consent", ResourceID: &consentID,
			RequestID: requestID, Result: "success", Detail: map[string]any{
				"subject_id": subjectPublicID, "consent_type": kind, "source": "subject_creation_selection", "notice_version": "creation-consents-v1",
			},
		}); err != nil {
			return err
		}
	}
	return createConsentSnapshot(ctx, tx, tenantID, subjectID)
}