-- Add directory support to files table
-- Migration: Add directory support for folder uploads

-- Add new columns to files table
ALTER TABLE files 
ADD COLUMN IF NOT EXISTS is_directory BOOLEAN DEFAULT FALSE,
ADD COLUMN IF NOT EXISTS parent_directory_id UUID REFERENCES files(id) ON DELETE CASCADE,
ADD COLUMN IF NOT EXISTS relative_path TEXT,
ADD COLUMN IF NOT EXISTS directory_manifest JSONB,
ADD COLUMN IF NOT EXISTS upload_session_id UUID,
ADD COLUMN IF NOT EXISTS processing_status TEXT DEFAULT 'uploaded' CHECK (processing_status IN ('uploaded', 'processing', 'completed', 'failed', 'queued'));

-- Create index for efficient directory queries
CREATE INDEX IF NOT EXISTS idx_files_parent_directory ON files(parent_directory_id);
CREATE INDEX IF NOT EXISTS idx_files_upload_session ON files(upload_session_id);
CREATE INDEX IF NOT EXISTS idx_files_processing_status ON files(processing_status);
CREATE INDEX IF NOT EXISTS idx_files_is_directory ON files(is_directory);

-- Create directory manifest structure
COMMENT ON COLUMN files.is_directory IS 'True if this record represents a directory/folder';
COMMENT ON COLUMN files.parent_directory_id IS 'ID of parent directory if this file is inside an uploaded folder';
COMMENT ON COLUMN files.relative_path IS 'Relative path within the uploaded directory structure';
COMMENT ON COLUMN files.directory_manifest IS 'JSON manifest of directory contents including file count, total size, structure';
COMMENT ON COLUMN files.upload_session_id IS 'Groups files uploaded together in a single directory upload session';
COMMENT ON COLUMN files.processing_status IS 'Simple status tracking without auto-processing';

-- Example directory_manifest structure:
-- {
--   "total_files": 15,
--   "total_size_bytes": 12345678,
--   "directory_structure": {
--     "documents/": {
--       "file1.pdf": {"size": 123456, "mime_type": "application/pdf"},
--       "subdirectory/": {
--         "file2.docx": {"size": 234567, "mime_type": "application/vnd.openxmlformats-officedocument.wordprocessingml.document"}
--       }
--     }
--   },
--   "upload_timestamp": "2024-09-23T12:00:00Z",
--   "upload_method": "directory_picker"
-- }