fsmon 0.1.6

pub enum HelpTopic {
    Root,
    Monitor,
    Query,
    Status,
    Stop,
    Start,
    Install,
    Uninstall,
    Clean,
    Generate,
}

pub const fn about(topic: HelpTopic) -> &'static str {
    match topic {
        HelpTopic::Root => "Lightweight high-performance file change tracking tool",
        HelpTopic::Monitor => "Real-time file change monitoring",
        HelpTopic::Query => "Query historical monitoring logs",
        HelpTopic::Status => "Check systemd service status",
        HelpTopic::Stop => "Stop systemd service",
        HelpTopic::Start => "Start systemd service",
        HelpTopic::Install => "Install systemd service",
        HelpTopic::Uninstall => "Uninstall systemd service",
        HelpTopic::Clean => "Clean historical logs",
        HelpTopic::Generate => "Generate a default config file",
    }
}

pub const fn long_about(topic: HelpTopic) -> &'static str {
    match topic {
        HelpTopic::Root => "",
        HelpTopic::Monitor => {
            r#"Monitor filesystem events on specified paths, output fanotify raw events in real-time.

[Event Types]
  Default: 8 core change events (CLOSE_WRITE, ATTRIB, CREATE, DELETE, DELETE_SELF, MOVED_FROM, MOVED_TO, MOVE_SELF)
  --all-events: Enable all 14 fanotify events (includes ACCESS, MODIFY, OPEN, OPEN_EXEC, CLOSE_NOWRITE, FS_ERROR)

[Systemd Service]
  Use 'fsmon install' to set up systemd service for long-term monitoring
  fsmon status/stop/start to manage service

[Examples]
  fsmon monitor /etc --types MODIFY          # Investigate config file changes
  fsmon monitor / --all-events               # Enable all 14 event types
  fsmon monitor ~/project --recursive        # Recursively monitor project directory
  fsmon monitor /tmp --min-size 100MB        # Track large file creation
  fsmon monitor /var/log --format json       # JSON format output"#
        }
        HelpTopic::Query => {
            r#"Query historical file change events from log files, supports multiple filter conditions and sorting.

[Time Filtering]
  --since   Start time: relative (1h, 30m, 7d) or absolute ("2024-05-01 10:00")
  --until   End time
  
[Process Filtering]
  --pid     Filter by process ID (multiple supported: 1234,5678)
  --cmd     Filter by process name (wildcard support: nginx*, python)
  --user    Filter by username (multiple supported: root,admin)

[Event Filtering]
  --types     Filter by event type (ACCESS,MODIFY,CREATE,DELETE,...)
  --min-size  Filter by size change (e.g., 100MB, 1GB)

[Examples]
  fsmon query                              # Query default log (~/.fsmon/history.log)
  fsmon query --since 1h                   # Last 1 hour
  fsmon query --cmd nginx                  # Only nginx operations
  fsmon query --since 1h --cmd java --types MODIFY --min-size 100MB  # Combined filters
  fsmon query --format json --sort size    # JSON output, sorted by size"#
        }
        HelpTopic::Status => {
            r#"Check fsmon systemd service status.

[Output Content]
  - Service status (active/inactive/failed)
  - Use 'systemctl status fsmon' for detailed information

[Examples]
  fsmon status"#
        }
        HelpTopic::Stop => {
            r#"Stop fsmon systemd service.

[Examples]
  fsmon stop"#
        }
        HelpTopic::Start => {
            r#"Start fsmon systemd service.

[Examples]
  fsmon start"#
        }
        HelpTopic::Install => {
            r#"Install fsmon as a systemd service.

[Service Configuration]
  - Creates /etc/systemd/system/fsmon.service
  - Configures auto-restart on failure
  - Logs to systemd journal

[Examples]
  fsmon install /var/log -o /var/log/fsmon.log    # Monitor /var/log
  fsmon install /etc /var/log                      # Monitor multiple paths"#
        }
        HelpTopic::Uninstall => {
            r#"Uninstall fsmon systemd service.

[Actions]
  - Stops service if running
  - Disables service
  - Removes service file

[Examples]
  fsmon uninstall"#
        }
        HelpTopic::Clean => {
            r#"Clean historical log files, retain by time or size.

[Cleanup Strategy]
  --keep-days   Keep logs from last N days (default: 30 days)
  --max-size    Limit maximum log file size (e.g., 100MB, 1GB)
  --dry-run     Preview mode, don't actually delete

[Examples]
  fsmon clean --keep-days 7           # Keep 7 days of logs
  fsmon clean --max-size 100MB        # Limit logs to 100MB
  fsmon clean --keep-days 7 --dry-run # Preview without deleting"#
        }
        HelpTopic::Generate => {
            "Generate a commented default configuration file.\n\
Generates a TOML config file at ~/.config/fsmon/config.toml (XDG config path).\n\
\n\
[Config Search Order]\n\
  1. ~/.fsmon/config.toml        (legacy)\n\
  2. ~/.config/fsmon/config.toml (XDG)\n\
  3. /etc/fsmon/config.toml      (system-wide)\n\
\n\
[Examples]\n\
  fsmon generate                  # Generate config (fails if exists)\n\
  fsmon generate --force          # Overwrite existing config"
        }
    }
}

pub const fn after_help() -> &'static str {
    r#"Use 'fsmon <COMMAND> --help' for detailed command info

Examples:
  fsmon monitor /var/log                     # Basic monitoring
  fsmon monitor /etc --types MODIFY         # Investigate config file changes
  fsmon monitor / --all-events               # Enable all 14 event types
  fsmon monitor ~/project --recursive       # Recursively monitor project
  fsmon install /var/log -o /var/log/fsmon.log  # Install systemd service
  fsmon query --since 1h --cmd nginx         # Query nginx operations in last hour
  fsmon status                               # Check service status"#
}