// Package dwn provides a client interface for interacting with the Sonr DWN (Decentralized Web Node) module.
package dwn

import (
	"context"
	"fmt"
	"time"

	"google.golang.org/grpc"

	"github.com/cosmos/cosmos-sdk/types/tx"

	"github.com/sonr-io/sonr/client/config"
	"github.com/sonr-io/sonr/client/errors"
	dwntypes "github.com/sonr-io/sonr/x/dwn/types"
)

// Client provides an interface for interacting with the DWN module.
type Client interface {
	// Record Operations
	CreateRecord(ctx context.Context, opts *CreateRecordOptions) (*Record, error)
	ReadRecord(ctx context.Context, recordID string) (*Record, error)
	UpdateRecord(ctx context.Context, recordID string, opts *UpdateRecordOptions) (*Record, error)
	DeleteRecord(ctx context.Context, recordID string) error

	// Query Operations
	QueryRecords(ctx context.Context, query *RecordQuery) (*RecordQueryResponse, error)
	ListRecords(ctx context.Context, opts *ListRecordsOptions) (*RecordListResponse, error)

	// Permission Operations
	GrantPermission(ctx context.Context, opts *GrantPermissionOptions) (*Permission, error)
	RevokePermission(ctx context.Context, permissionID string) error
	ListPermissions(ctx context.Context, opts *ListPermissionsOptions) (*PermissionListResponse, error)

	// Protocol Operations
	InstallProtocol(ctx context.Context, protocol *Protocol) error
	UninstallProtocol(ctx context.Context, protocolURI string) error
	ListProtocols(ctx context.Context) ([]*Protocol, error)

	// Encryption Operations
	EncryptRecord(ctx context.Context, recordID string, opts *EncryptionOptions) error
	DecryptRecord(ctx context.Context, recordID string) (*DecryptedRecord, error)

	// Vault Operations
	CreateVault(ctx context.Context, opts *VaultOptions) (*Vault, error)
	ListVaults(ctx context.Context) ([]*Vault, error)
	ExportVault(ctx context.Context, vaultID string) (*VaultExport, error)
	ImportVault(ctx context.Context, vaultData *VaultExport) (*Vault, error)
}

// Record represents a DWN record.
type Record struct {
	ID          string         `json:"id"`
	DID         string         `json:"did"`
	SchemaURI   string         `json:"schema_uri,omitempty"`
	ProtocolURI string         `json:"protocol_uri,omitempty"`
	ContextID   string         `json:"context_id,omitempty"`
	ParentID    string         `json:"parent_id,omitempty"`
	Data        []byte         `json:"data"`
	Metadata    map[string]any `json:"metadata,omitempty"`
	Encrypted   bool           `json:"encrypted"`
	CreatedAt   string         `json:"created_at"`
	UpdatedAt   string         `json:"updated_at,omitempty"`
	Tags        []string       `json:"tags,omitempty"`
}

// CreateRecordOptions configures record creation.
type CreateRecordOptions struct {
	DID         string         `json:"did"`
	SchemaURI   string         `json:"schema_uri,omitempty"`
	ProtocolURI string         `json:"protocol_uri,omitempty"`
	ContextID   string         `json:"context_id,omitempty"`
	ParentID    string         `json:"parent_id,omitempty"`
	Data        []byte         `json:"data"`
	Metadata    map[string]any `json:"metadata,omitempty"`
	Encrypt     bool           `json:"encrypt,omitempty"`
	Tags        []string       `json:"tags,omitempty"`
}

// UpdateRecordOptions configures record updates.
type UpdateRecordOptions struct {
	Data     []byte         `json:"data,omitempty"`
	Metadata map[string]any `json:"metadata,omitempty"`
	Tags     []string       `json:"tags,omitempty"`
}

// RecordQuery defines query parameters for records.
type RecordQuery struct {
	DID         string            `json:"did,omitempty"`
	SchemaURI   string            `json:"schema_uri,omitempty"`
	ProtocolURI string            `json:"protocol_uri,omitempty"`
	ContextID   string            `json:"context_id,omitempty"`
	ParentID    string            `json:"parent_id,omitempty"`
	Tags        []string          `json:"tags,omitempty"`
	Metadata    map[string]string `json:"metadata,omitempty"`
	DateRange   *DateRange        `json:"date_range,omitempty"`
}

// DateRange specifies a date range for queries.
type DateRange struct {
	From string `json:"from,omitempty"`
	To   string `json:"to,omitempty"`
}

// RecordQueryResponse contains query results.
type RecordQueryResponse struct {
	Records    []*Record `json:"records"`
	TotalCount uint64    `json:"total_count"`
	Limit      uint64    `json:"limit"`
	Offset     uint64    `json:"offset"`
}

// ListRecordsOptions configures record listing.
type ListRecordsOptions struct {
	DID    string `json:"did,omitempty"`
	Limit  uint64 `json:"limit,omitempty"`
	Offset uint64 `json:"offset,omitempty"`
}

// RecordListResponse contains a list of records.
type RecordListResponse struct {
	Records    []*Record `json:"records"`
	TotalCount uint64    `json:"total_count"`
	Limit      uint64    `json:"limit"`
	Offset     uint64    `json:"offset"`
}

// Permission represents a DWN permission.
type Permission struct {
	ID         string         `json:"id"`
	Grantor    string         `json:"grantor"`
	Grantee    string         `json:"grantee"`
	Scope      string         `json:"scope"`
	Actions    []string       `json:"actions"`
	Conditions map[string]any `json:"conditions,omitempty"`
	ExpiresAt  string         `json:"expires_at,omitempty"`
	CreatedAt  string         `json:"created_at"`
}

// GrantPermissionOptions configures permission granting.
type GrantPermissionOptions struct {
	Grantee    string         `json:"grantee"`
	Scope      string         `json:"scope"`
	Actions    []string       `json:"actions"`
	Conditions map[string]any `json:"conditions,omitempty"`
	ExpiresAt  string         `json:"expires_at,omitempty"`
}

// ListPermissionsOptions configures permission listing.
type ListPermissionsOptions struct {
	Grantee string `json:"grantee,omitempty"`
	Scope   string `json:"scope,omitempty"`
	Limit   uint64 `json:"limit,omitempty"`
	Offset  uint64 `json:"offset,omitempty"`
}

// PermissionListResponse contains a list of permissions.
type PermissionListResponse struct {
	Permissions []*Permission `json:"permissions"`
	TotalCount  uint64        `json:"total_count"`
	Limit       uint64        `json:"limit"`
	Offset      uint64        `json:"offset"`
}

// Protocol represents a DWN protocol.
type Protocol struct {
	URI         string         `json:"uri"`
	Name        string         `json:"name"`
	Version     string         `json:"version"`
	Description string         `json:"description,omitempty"`
	Schema      map[string]any `json:"schema"`
	Rules       map[string]any `json:"rules,omitempty"`
	CreatedAt   string         `json:"created_at"`
}

// EncryptionOptions configures record encryption.
type EncryptionOptions struct {
	Algorithm     string         `json:"algorithm,omitempty"`
	Recipients    []string       `json:"recipients,omitempty"`
	KeyDerivation map[string]any `json:"key_derivation,omitempty"`
}

// DecryptedRecord contains decrypted record data.
type DecryptedRecord struct {
	Record    *Record `json:"record"`
	Data      []byte  `json:"data"`
	Algorithm string  `json:"algorithm"`
}

// Vault represents a DWN vault.
type Vault struct {
	ID        string         `json:"id"`
	DID       string         `json:"did"`
	Name      string         `json:"name"`
	Type      string         `json:"type"`
	Config    map[string]any `json:"config"`
	CreatedAt string         `json:"created_at"`
	UpdatedAt string         `json:"updated_at,omitempty"`
}

// VaultOptions configures vault creation.
type VaultOptions struct {
	DID    string         `json:"did"`
	Name   string         `json:"name"`
	Type   string         `json:"type,omitempty"`
	Config map[string]any `json:"config,omitempty"`
}

// VaultExport contains exported vault data.
type VaultExport struct {
	Vault     *Vault         `json:"vault"`
	Records   []*Record      `json:"records"`
	Protocols []*Protocol    `json:"protocols"`
	Metadata  map[string]any `json:"metadata"`
}

// client implements the DWN Client interface.
type client struct {
	grpcConn *grpc.ClientConn
	config   *config.NetworkConfig

	// Service clients for DWN module
	queryClient dwntypes.QueryClient
	msgClient   dwntypes.MsgClient
	txClient    tx.ServiceClient
}

// NewClient creates a new DWN module client.
func NewClient(grpcConn *grpc.ClientConn, cfg *config.NetworkConfig) Client {
	return &client{
		grpcConn:    grpcConn,
		config:      cfg,
		queryClient: dwntypes.NewQueryClient(grpcConn),
		msgClient:   dwntypes.NewMsgClient(grpcConn),
		txClient:    tx.NewServiceClient(grpcConn),
	}
}

// CreateRecord creates a new record in the DWN.
func (c *client) CreateRecord(ctx context.Context, opts *CreateRecordOptions) (*Record, error) {
	// TODO: Implement record creation using DWN module
	// Should build MsgRecordsWrite with proper descriptor
	// Validate record data size and format
	// Handle encryption if requested in options
	// Submit transaction and return created record with ID

	return nil, errors.NewModuleError("dwn", "CreateRecord",
		fmt.Errorf("record creation not yet implemented"))
}

// ReadRecord retrieves a record by ID.
func (c *client) ReadRecord(ctx context.Context, recordID string) (*Record, error) {
	// TODO: Implement record reading using DWN module query client
	// Should query chain state for record by ID
	// Check read permissions and UCAN authorization
	// Decrypt record data if encrypted
	// Return complete record with metadata

	return nil, errors.NewModuleError("dwn", "ReadRecord",
		fmt.Errorf("record reading not yet implemented"))
}

// UpdateRecord updates an existing record.
func (c *client) UpdateRecord(ctx context.Context, recordID string, opts *UpdateRecordOptions) (*Record, error) {
	// TODO: Implement record updates using DWN module
	// Should validate record ownership and update permissions
	// Build MsgRecordsWrite with updated data
	// Preserve original record metadata unless modified
	// Handle encryption for updated data

	return nil, errors.NewModuleError("dwn", "UpdateRecord",
		fmt.Errorf("record updates not yet implemented"))
}

// DeleteRecord deletes a record.
func (c *client) DeleteRecord(ctx context.Context, recordID string) error {
	// TODO: Implement record deletion using DWN module
	// Should validate record ownership and delete permissions
	// Build MsgRecordsDelete and submit to chain
	// Handle soft delete vs hard delete based on protocol
	// Clean up associated IPFS data if applicable

	return errors.NewModuleError("dwn", "DeleteRecord",
		fmt.Errorf("record deletion not yet implemented"))
}

// QueryRecords queries records based on specified criteria.
func (c *client) QueryRecords(ctx context.Context, query *RecordQuery) (*RecordQueryResponse, error) {
	// TODO: Implement record querying using DWN module
	// Should support complex queries with multiple filters
	// Filter by DID, schema, protocol, context, parent
	// Support date range and tag-based filtering
	// Return paginated results with total count

	return nil, errors.NewModuleError("dwn", "QueryRecords",
		fmt.Errorf("record querying not yet implemented"))
}

// ListRecords lists records with pagination.
func (c *client) ListRecords(ctx context.Context, opts *ListRecordsOptions) (*RecordListResponse, error) {
	// TODO: Implement record listing using DWN module
	// Should support pagination with limit/offset
	// Filter by DID if specified
	// Return records with basic metadata
	// Handle empty result sets gracefully

	return nil, errors.NewModuleError("dwn", "ListRecords",
		fmt.Errorf("record listing not yet implemented"))
}

// GrantPermission grants a permission to access records.
func (c *client) GrantPermission(ctx context.Context, opts *GrantPermissionOptions) (*Permission, error) {
	// TODO: Implement permission granting using DWN module
	// Should build MsgPermissionsGrant with proper conditions
	// Validate grantee DID and permission scope
	// Set expiration and action restrictions
	// Return permission record with unique ID

	return nil, errors.NewModuleError("dwn", "GrantPermission",
		fmt.Errorf("permission granting not yet implemented"))
}

// RevokePermission revokes a previously granted permission.
func (c *client) RevokePermission(ctx context.Context, permissionID string) error {
	// TODO: Implement permission revocation using DWN module
	// Should build MsgPermissionsRevoke and submit to chain
	// Validate permission ownership before revocation
	// Update permission status to revoked
	// Notify affected systems of permission changes

	return errors.NewModuleError("dwn", "RevokePermission",
		fmt.Errorf("permission revocation not yet implemented"))
}

// ListPermissions lists permissions with optional filtering.
func (c *client) ListPermissions(ctx context.Context, opts *ListPermissionsOptions) (*PermissionListResponse, error) {
	// TODO: Implement permission listing using DWN module
	// Should support filtering by grantee, scope, status
	// Include permission expiration and condition info
	// Support pagination with limit/offset
	// Return permissions with grant metadata

	return nil, errors.NewModuleError("dwn", "ListPermissions",
		fmt.Errorf("permission listing not yet implemented"))
}

// InstallProtocol installs a new protocol.
func (c *client) InstallProtocol(ctx context.Context, protocol *Protocol) error {
	// TODO: Implement protocol installation using DWN module
	// Should build MsgProtocolsConfigure and submit to chain
	// Validate protocol schema and rules format
	// Check protocol URI uniqueness and versioning
	// Store protocol definition for record validation

	return errors.NewModuleError("dwn", "InstallProtocol",
		fmt.Errorf("protocol installation not yet implemented"))
}

// UninstallProtocol uninstalls a protocol.
func (c *client) UninstallProtocol(ctx context.Context, protocolURI string) error {
	// TODO: Implement protocol uninstallation using DWN module
	// Should check for existing records using this protocol
	// Prevent uninstallation if records depend on protocol
	// Remove protocol definition from storage
	// Handle graceful protocol deprecation

	return errors.NewModuleError("dwn", "UninstallProtocol",
		fmt.Errorf("protocol uninstallation not yet implemented"))
}

// ListProtocols lists installed protocols.
func (c *client) ListProtocols(ctx context.Context) ([]*Protocol, error) {
	// TODO: Implement protocol listing using DWN module
	// Should query chain state for installed protocols
	// Return protocols with schema, rules, and version info
	// Include protocol usage statistics if available
	// Handle empty protocol list gracefully

	return nil, errors.NewModuleError("dwn", "ListProtocols",
		fmt.Errorf("protocol listing not yet implemented"))
}

// EncryptRecord encrypts a record.
func (c *client) EncryptRecord(ctx context.Context, recordID string, opts *EncryptionOptions) error {
	// TODO: Implement record encryption using DWN module
	// Should validate record ownership and encryption options
	// Use AES-GCM with secure key derivation from recipients
	// Store encrypted data with authentication tag
	// Update record metadata to mark as encrypted

	return errors.NewModuleError("dwn", "EncryptRecord",
		fmt.Errorf("record encryption not yet implemented"))
}

// DecryptRecord decrypts a record.
func (c *client) DecryptRecord(ctx context.Context, recordID string) (*DecryptedRecord, error) {
	// TODO: Implement record decryption using DWN module
	// Should validate decryption permissions and key access
	// Use stored encryption algorithm and key derivation
	// Verify authentication tag before returning data
	// Return decrypted record with original format info

	return nil, errors.NewModuleError("dwn", "DecryptRecord",
		fmt.Errorf("record decryption not yet implemented"))
}

// CreateVault creates a new vault.
func (c *client) CreateVault(ctx context.Context, opts *VaultOptions) (*Vault, error) {
	// TODO: Implement vault creation using DWN module and Motor plugin
	// Should validate DID ownership and vault configuration
	// Use Motor WASM enclave for secure vault initialization
	// Generate vault keys using hardware-backed security
	// Store vault metadata on chain with IPFS references

	return nil, errors.NewModuleError("dwn", "CreateVault",
		fmt.Errorf("vault creation not yet implemented"))
}

// ListVaults lists available vaults.
func (c *client) ListVaults(ctx context.Context) ([]*Vault, error) {
	// TODO: Implement vault listing using DWN module
	// Should query chain state for user vaults
	// Return vaults with metadata and configuration
	// Include vault status and last update information
	// Handle access permissions for vault visibility

	return nil, errors.NewModuleError("dwn", "ListVaults",
		fmt.Errorf("vault listing not yet implemented"))
}

// ExportVault exports vault data.
func (c *client) ExportVault(ctx context.Context, vaultID string) (*VaultExport, error) {
	// TODO: Implement vault export using DWN module and Motor plugin
	// Should validate vault ownership and export permissions
	// Use Motor plugin to securely export vault contents
	// Include all records, protocols, and permissions
	// Encrypt export data for secure transfer

	return nil, errors.NewModuleError("dwn", "ExportVault",
		fmt.Errorf("vault export not yet implemented"))
}

// ImportVault imports vault data.
func (c *client) ImportVault(ctx context.Context, vaultData *VaultExport) (*Vault, error) {
	// TODO: Implement vault import using DWN module and Motor plugin
	// Should validate import data integrity and format
	// Use Motor plugin to securely import vault contents
	// Restore records, protocols, and permissions
	// Handle conflicts with existing data gracefully

	return nil, errors.NewModuleError("dwn", "ImportVault",
		fmt.Errorf("vault import not yet implemented"))
}

// Utility functions

// GenerateRecordID generates a unique record ID.
func GenerateRecordID() string {
	// TODO: Implement proper record ID generation
	return fmt.Sprintf("record_%d", time.Now().UnixNano())
}

// ValidateRecordData validates record data.
func ValidateRecordData(data []byte) error {
	if len(data) == 0 {
		return fmt.Errorf("record data cannot be empty")
	}

	// Add size limits and other validation as needed
	if len(data) > 10*1024*1024 { // 10MB limit
		return fmt.Errorf("record data too large")
	}

	return nil
}

// CreateDefaultProtocol creates a default protocol configuration.
func CreateDefaultProtocol(name, version string) *Protocol {
	return &Protocol{
		URI:         fmt.Sprintf("https://protocols.sonr.io/%s/%s", name, version),
		Name:        name,
		Version:     version,
		Description: fmt.Sprintf("Default protocol for %s", name),
		Schema:      map[string]any{},
		Rules:       map[string]any{},
	}
}

// Message Builders - These create the actual transaction messages

// BuildMsgRecordsWrite builds a MsgRecordsWrite message.
func BuildMsgRecordsWrite(author, target string, opts *CreateRecordOptions) (*dwntypes.MsgRecordsWrite, error) {
	if opts == nil {
		return nil, fmt.Errorf("options cannot be nil")
	}

	// Create message descriptor
	descriptor := &dwntypes.DWNMessageDescriptor{
		InterfaceName:    "Records",
		Method:           "Write",
		MessageTimestamp: time.Now().Format(time.RFC3339),
		DataFormat:       "application/json", // Default format
		DataSize:         int64(len(opts.Data)),
	}

	return &dwntypes.MsgRecordsWrite{
		Author:        author,
		Target:        target,
		Descriptor_:   descriptor,
		Authorization: "", // Will be set by the transaction builder
		Data:          opts.Data,
	}, nil
}

// BuildMsgRecordsDelete builds a MsgRecordsDelete message.
func BuildMsgRecordsDelete(author, target, recordID string) (*dwntypes.MsgRecordsDelete, error) {
	if recordID == "" {
		return nil, fmt.Errorf("record ID cannot be empty")
	}

	// Create message descriptor
	descriptor := &dwntypes.DWNMessageDescriptor{
		InterfaceName:    "Records",
		Method:           "Delete",
		MessageTimestamp: time.Now().Format(time.RFC3339),
	}

	return &dwntypes.MsgRecordsDelete{
		Author:        author,
		Target:        target,
		RecordId:      recordID,
		Descriptor_:   descriptor,
		Authorization: "", // Will be set by the transaction builder
	}, nil
}

// BuildMsgProtocolsConfigure builds a MsgProtocolsConfigure message.
func BuildMsgProtocolsConfigure(author, target string, protocol *Protocol) (*dwntypes.MsgProtocolsConfigure, error) {
	if protocol == nil {
		return nil, fmt.Errorf("protocol cannot be nil")
	}

	// Create message descriptor
	descriptor := &dwntypes.DWNMessageDescriptor{
		InterfaceName:    "Protocols",
		Method:           "Configure",
		MessageTimestamp: time.Now().Format(time.RFC3339),
	}

	// Note: The actual protocol definition would need to be serialized
	// This is a placeholder implementation
	return &dwntypes.MsgProtocolsConfigure{
		Author:        author,
		Target:        target,
		Descriptor_:   descriptor,
		Authorization: "", // Will be set by the transaction builder
		// Definition would be set here based on the protocol
	}, nil
}

// BuildMsgPermissionsGrant builds a MsgPermissionsGrant message.
func BuildMsgPermissionsGrant(grantor, grantee, target string, grant *GrantPermissionOptions) (*dwntypes.MsgPermissionsGrant, error) {
	if grant == nil {
		return nil, fmt.Errorf("permission grant cannot be nil")
	}

	// Create message descriptor
	descriptor := &dwntypes.DWNMessageDescriptor{
		InterfaceName:    "Permissions",
		Method:           "Grant",
		MessageTimestamp: time.Now().Format(time.RFC3339),
	}

	// Note: The actual permission grant would need to be serialized
	// This is a placeholder implementation
	return &dwntypes.MsgPermissionsGrant{
		Grantor:       grantor,
		Grantee:       grantee,
		Target:        target,
		Descriptor_:   descriptor,
		Authorization: "", // Will be set by the transaction builder
		// PermissionGrant would be set here
	}, nil
}

// BuildMsgPermissionsRevoke builds a MsgPermissionsRevoke message.
func BuildMsgPermissionsRevoke(grantor, permissionID string) (*dwntypes.MsgPermissionsRevoke, error) {
	if permissionID == "" {
		return nil, fmt.Errorf("permission ID cannot be empty")
	}

	// Create message descriptor
	descriptor := &dwntypes.DWNMessageDescriptor{
		InterfaceName:    "Permissions",
		Method:           "Revoke",
		MessageTimestamp: time.Now().Format(time.RFC3339),
	}

	return &dwntypes.MsgPermissionsRevoke{
		Grantor:       grantor,
		PermissionId:  permissionID,
		Descriptor_:   descriptor,
		Authorization: "", // Will be set by the transaction builder
	}, nil
}

// BuildMsgRotateVaultKeys builds a MsgRotateVaultKeys message.
func BuildMsgRotateVaultKeys(authority, vaultID string) *dwntypes.MsgRotateVaultKeys {
	return &dwntypes.MsgRotateVaultKeys{
		Authority: authority,
		VaultId:   vaultID,
	}
}