package usecase

import (
	"context"

	"backend/pkg/post/domain/post"

	"github.com/gocql/gocql"
)

// PostUseCase defines the interface for post business logic operations
type PostUseCase interface {
	PostCRUDUseCase
	PostQueryUseCase
	PostInteractionUseCase
	PostManagementUseCase
}

// PostCRUDUseCase defines CRUD operations for posts
type PostCRUDUseCase interface {
	// CreatePost creates a new post
	CreatePost(ctx context.Context, req CreatePostRequest) (*PostResponse, error)
	// GetPost retrieves a post by ID
	GetPost(ctx context.Context, req GetPostRequest) (*PostResponse, error)
	// UpdatePost updates an existing post
	UpdatePost(ctx context.Context, req UpdatePostRequest) (*PostResponse, error)
	// DeletePost deletes a post (soft delete)
	DeletePost(ctx context.Context, req DeletePostRequest) error
	// PublishPost publishes a draft post
	PublishPost(ctx context.Context, req PublishPostRequest) (*PostResponse, error)
	// ArchivePost archives a post
	ArchivePost(ctx context.Context, req ArchivePostRequest) error
}

// PostQueryUseCase defines query operations for posts
type PostQueryUseCase interface {
	// ListPosts lists posts with filters and pagination
	ListPosts(ctx context.Context, req ListPostsRequest) (*ListPostsResponse, error)
	// ListPostsByAuthor lists posts by author UID
	ListPostsByAuthor(ctx context.Context, req ListPostsByAuthorRequest) (*ListPostsResponse, error)
	// ListPostsByCategory lists posts by category
	ListPostsByCategory(ctx context.Context, req ListPostsByCategoryRequest) (*ListPostsResponse, error)
	// ListPostsByTag lists posts by tag
	ListPostsByTag(ctx context.Context, req ListPostsByTagRequest) (*ListPostsResponse, error)
	// GetPinnedPosts gets pinned posts
	GetPinnedPosts(ctx context.Context, req GetPinnedPostsRequest) (*ListPostsResponse, error)
}

// PostInteractionUseCase defines interaction operations for posts
type PostInteractionUseCase interface {
	// LikePost likes a post
	LikePost(ctx context.Context, req LikePostRequest) error
	// UnlikePost unlikes a post
	UnlikePost(ctx context.Context, req UnlikePostRequest) error
	// ViewPost increments view count
	ViewPost(ctx context.Context, req ViewPostRequest) error
}

// PostManagementUseCase defines management operations for posts
type PostManagementUseCase interface {
	// PinPost pins a post
	PinPost(ctx context.Context, req PinPostRequest) error
	// UnpinPost unpins a post
	UnpinPost(ctx context.Context, req UnpinPostRequest) error
}

// CreatePostRequest represents a request to create a post
type CreatePostRequest struct {
	AuthorUID  string          `json:"author_uid"`            // Author user UID
	Title      string          `json:"title"`                 // Post title
	Content    string          `json:"content"`               // Post content
	Type       post.Type       `json:"type"`                  // Post type
	CategoryID *gocql.UUID     `json:"category_id,omitempty"`  // Category ID (optional)
	Tags       []string        `json:"tags,omitempty"`         // Post tags (optional)
	Images     []string        `json:"images,omitempty"`       // Image URLs (optional)
	VideoURL   *string         `json:"video_url,omitempty"`   // Video URL (optional)
	LinkURL    *string         `json:"link_url,omitempty"`    // Link URL (optional)
	Status     post.Status     `json:"status,omitempty"`       // Post status (default: draft)
}

// UpdatePostRequest represents a request to update a post
type UpdatePostRequest struct {
	PostID     gocql.UUID      `json:"post_id"`               // Post ID
	AuthorUID  string          `json:"author_uid"`             // Author user UID (for authorization)
	Title      *string         `json:"title,omitempty"`       // Post title (optional)
	Content    *string         `json:"content,omitempty"`      // Post content (optional)
	Type       *post.Type      `json:"type,omitempty"`         // Post type (optional)
	CategoryID *gocql.UUID     `json:"category_id,omitempty"`  // Category ID (optional)
	Tags       []string        `json:"tags,omitempty"`         // Post tags (optional)
	Images     []string        `json:"images,omitempty"`      // Image URLs (optional)
	VideoURL   *string         `json:"video_url,omitempty"`   // Video URL (optional)
	LinkURL    *string         `json:"link_url,omitempty"`    // Link URL (optional)
}

// GetPostRequest represents a request to get a post
type GetPostRequest struct {
	PostID    gocql.UUID `json:"post_id"`              // Post ID
	UserUID   *string    `json:"user_uid,omitempty"`   // User UID (for view count increment)
}

// DeletePostRequest represents a request to delete a post
type DeletePostRequest struct {
	PostID   gocql.UUID `json:"post_id"`   // Post ID
	AuthorUID string    `json:"author_uid"` // Author user UID (for authorization)
}

// PublishPostRequest represents a request to publish a post
type PublishPostRequest struct {
	PostID   gocql.UUID `json:"post_id"`   // Post ID
	AuthorUID string    `json:"author_uid"` // Author user UID (for authorization)
}

// ArchivePostRequest represents a request to archive a post
type ArchivePostRequest struct {
	PostID   gocql.UUID `json:"post_id"`   // Post ID
	AuthorUID string    `json:"author_uid"` // Author user UID (for authorization)
}

// ListPostsRequest represents a request to list posts
type ListPostsRequest struct {
	CategoryID     *gocql.UUID  `json:"category_id,omitempty"`     // Category ID (optional)
	Tag            *string      `json:"tag,omitempty"`             // Tag name (optional)
	Status         *post.Status `json:"status,omitempty"`         // Post status (optional)
	Type           *post.Type   `json:"type,omitempty"`            // Post type (optional)
	AuthorUID      *string      `json:"author_uid,omitempty"`      // Author UID (optional)
	CreateStartTime *int64      `json:"create_start_time,omitempty"` // Create start time (optional)
	CreateEndTime   *int64      `json:"create_end_time,omitempty"`   // Create end time (optional)
	PageSize       int64        `json:"page_size"`                 // Page size
	PageIndex      int64        `json:"page_index"`               // Page index
	OrderBy        string       `json:"order_by,omitempty"`        // Order by field
	OrderDirection string       `json:"order_direction,omitempty"` // Order direction (ASC/DESC)
}

// ListPostsByAuthorRequest represents a request to list posts by author
type ListPostsByAuthorRequest struct {
	AuthorUID string       `json:"author_uid"`        // Author UID
	Status    *post.Status `json:"status,omitempty"` // Post status (optional)
	PageSize  int64       `json:"page_size"`         // Page size
	PageIndex int64       `json:"page_index"`         // Page index
}

// ListPostsByCategoryRequest represents a request to list posts by category
type ListPostsByCategoryRequest struct {
	CategoryID gocql.UUID  `json:"category_id"`       // Category ID
	Status     *post.Status `json:"status,omitempty"` // Post status (optional)
	PageSize   int64       `json:"page_size"`         // Page size
	PageIndex  int64       `json:"page_index"`        // Page index
}

// ListPostsByTagRequest represents a request to list posts by tag
type ListPostsByTagRequest struct {
	Tag      string       `json:"tag"`                // Tag name
	Status   *post.Status `json:"status,omitempty"`   // Post status (optional)
	PageSize int64       `json:"page_size"`           // Page size
	PageIndex int64      `json:"page_index"`          // Page index
}

// GetPinnedPostsRequest represents a request to get pinned posts
type GetPinnedPostsRequest struct {
	Limit int64 `json:"limit,omitempty"` // Limit (optional, default: 10)
}

// LikePostRequest represents a request to like a post
type LikePostRequest struct {
	PostID  gocql.UUID `json:"post_id"`  // Post ID
	UserUID string     `json:"user_uid"` // User UID
}

// UnlikePostRequest represents a request to unlike a post
type UnlikePostRequest struct {
	PostID  gocql.UUID `json:"post_id"`  // Post ID
	UserUID string     `json:"user_uid"` // User UID
}

// ViewPostRequest represents a request to view a post
type ViewPostRequest struct {
	PostID  gocql.UUID `json:"post_id"`  // Post ID
	UserUID *string    `json:"user_uid,omitempty"` // User UID (optional)
}

// PinPostRequest represents a request to pin a post
type PinPostRequest struct {
	PostID   gocql.UUID `json:"post_id"`   // Post ID
	AuthorUID string    `json:"author_uid"` // Author user UID (for authorization)
}

// UnpinPostRequest represents a request to unpin a post
type UnpinPostRequest struct {
	PostID   gocql.UUID `json:"post_id"`   // Post ID
	AuthorUID string    `json:"author_uid"` // Author user UID (for authorization)
}

// PostResponse represents a post response
type PostResponse struct {
	ID           gocql.UUID      `json:"id"`
	AuthorUID    string          `json:"author_uid"`
	Title        string          `json:"title"`
	Content      string          `json:"content"`
	Type         post.Type       `json:"type"`
	Status       post.Status     `json:"status"`
	CategoryID   *gocql.UUID     `json:"category_id,omitempty"`
	Tags         []string        `json:"tags,omitempty"`
	Images       []string        `json:"images,omitempty"`
	VideoURL     *string         `json:"video_url,omitempty"`
	LinkURL      *string         `json:"link_url,omitempty"`
	LikeCount    int64           `json:"like_count"`
	CommentCount int64           `json:"comment_count"`
	ViewCount    int64           `json:"view_count"`
	IsPinned     bool            `json:"is_pinned"`
	PinnedAt     *int64          `json:"pinned_at,omitempty"`
	PublishedAt  *int64          `json:"published_at,omitempty"`
	CreatedAt    int64           `json:"created_at"`
	UpdatedAt    int64           `json:"updated_at"`
}

// ListPostsResponse represents a list of posts response
type ListPostsResponse struct {
	Data []PostResponse `json:"data"`
	Page Pager         `json:"page"`
}

// Pager represents pagination information
type Pager struct {
	PageIndex int64 `json:"page_index"`
	PageSize  int64 `json:"page_size"`
	Total     int64 `json:"total"`
	TotalPage int64 `json:"total_page"`
}