-- Add file_mtime column to media_items table for incremental scanning
-- Stores Unix timestamp in seconds of the file's modification time

ALTER TABLE media_items ADD COLUMN file_mtime BIGINT;

-- Create index for quick mtime lookups
CREATE INDEX IF NOT EXISTS idx_media_items_file_mtime ON media_items(file_mtime);

-- Create a scan_history table to track when each directory was last scanned
CREATE TABLE IF NOT EXISTS scan_history (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    directory TEXT NOT NULL UNIQUE,
    last_scan_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    files_scanned INTEGER NOT NULL DEFAULT 0,
    files_changed INTEGER NOT NULL DEFAULT 0,
    scan_duration_ms INTEGER
);

CREATE INDEX IF NOT EXISTS idx_scan_history_directory ON scan_history(directory);