backbone-bucket 0.3.0

//! State machine for FileShare workflow
//!
//! Generated by metaphor-schema

use serde::{Deserialize, Serialize};
use std::str::FromStr;

/// States for FileShare workflow
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Serialize, Deserialize)]
#[serde(rename_all = "snake_case")]
pub enum FileShareState {
    /// Initial state
    Active,
    /// Final state
    Inactive,
    /// Final state
    Expired,
    /// Final state
    Exhausted,
    /// Final state
    Revoked,
}

impl Default for FileShareState {
    fn default() -> Self {
        Self::Active
    }
}

impl std::fmt::Display for FileShareState {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            Self::Active => write!(f, "active"),
            Self::Inactive => write!(f, "inactive"),
            Self::Expired => write!(f, "expired"),
            Self::Exhausted => write!(f, "exhausted"),
            Self::Revoked => write!(f, "revoked"),
        }
    }
}

impl FromStr for FileShareState {
    type Err = StateMachineError;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        match s.to_lowercase().as_str() {
            "active" => Ok(Self::Active),
            "inactive" => Ok(Self::Inactive),
            "expired" => Ok(Self::Expired),
            "exhausted" => Ok(Self::Exhausted),
            "revoked" => Ok(Self::Revoked),
            _ => Err(StateMachineError::InvalidState(s.to_string())),
        }
    }
}

impl FileShareState {
    /// Check if this is the initial state
    pub fn is_initial(&self) -> bool {
        matches!(self, Self::Active)
    }

    /// Check if this is a final state
    pub fn is_final(&self) -> bool {
        matches!(self, Self::Inactive | Self::Expired | Self::Exhausted | Self::Revoked)
    }

    /// Get all possible states
    pub fn all() -> Vec<Self> {
        vec![
            Self::Active,
            Self::Inactive,
            Self::Expired,
            Self::Exhausted,
            Self::Revoked,
        ]
    }
}

/// Transitions for FileShare workflow
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Serialize, Deserialize)]
#[serde(rename_all = "snake_case")]
pub enum FileShareTransition {
    /// active -> expired
    Expire,
    /// active -> exhausted
    Exhaust,
    /// active -> revoked
    Revoke,
}

impl std::fmt::Display for FileShareTransition {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            Self::Expire => write!(f, "expire"),
            Self::Exhaust => write!(f, "exhaust"),
            Self::Revoke => write!(f, "revoke"),
        }
    }
}

impl FromStr for FileShareTransition {
    type Err = StateMachineError;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        match s.to_lowercase().as_str() {
            "expire" => Ok(Self::Expire),
            "exhaust" => Ok(Self::Exhaust),
            "revoke" => Ok(Self::Revoke),
            _ => Err(StateMachineError::InvalidTransition(s.to_string())),
        }
    }
}

impl FileShareTransition {
    /// Get the target state of this transition
    pub fn target_state(&self) -> FileShareState {
        match self {
            Self::Expire => FileShareState::Expired,
            Self::Exhaust => FileShareState::Exhausted,
            Self::Revoke => FileShareState::Revoked,
        }
    }

    /// Get all transitions
    pub fn all() -> Vec<Self> {
        vec![
            Self::Expire,
            Self::Exhaust,
            Self::Revoke,
        ]
    }

    /// Get allowed roles for this transition
    pub fn allowed_roles(&self) -> &'static [&'static str] {
        match self {
            Self::Expire => &["system"],
            Self::Exhaust => &["system"],
            Self::Revoke => &["admin", "owner"],
        }
    }
}

use super::StateMachineError;

/// State machine for FileShare workflow
#[derive(Debug, Clone)]
pub struct FileShareStateMachine {
    current_state: FileShareState,
}

impl FileShareStateMachine {
    /// Create a new state machine with initial state
    pub fn new() -> Self {
        Self {
            current_state: FileShareState::default(),
        }
    }

    /// Create from an existing state
    pub fn from_state(state: FileShareState) -> Self {
        Self { current_state: state }
    }

    /// Get the current state
    pub fn current_state(&self) -> FileShareState {
        self.current_state
    }

    /// Check if a transition is allowed from the current state
    pub fn can_transition(&self, transition: FileShareTransition) -> bool {
        if matches!(self.current_state, FileShareState::Inactive | FileShareState::Expired | FileShareState::Exhausted | FileShareState::Revoked) {
            return false;
        }

        match (self.current_state, transition) {
            (FileShareState::Active, FileShareTransition::Expire) => true,
            (FileShareState::Active, FileShareTransition::Exhaust) => true,
            (FileShareState::Active, FileShareTransition::Revoke) => true,
            _ => false,
        }
    }

    /// Check if a transition is allowed for a given role
    pub fn can_transition_with_role(&self, transition: FileShareTransition, role: &str) -> bool {
        if !self.can_transition(transition) {
            return false;
        }

        let allowed_roles = transition.allowed_roles();
        if allowed_roles.is_empty() {
            return true; // No role restriction
        }

        allowed_roles.iter().any(|r| *r == role || *r == "*")
    }

    /// Apply a transition, returning the new state
    pub fn transition(&mut self, transition: FileShareTransition) -> Result<FileShareState, StateMachineError> {
        if !self.can_transition(transition) {
            return Err(StateMachineError::TransitionNotAllowed {
                transition: transition.to_string(),
                from: self.current_state.to_string(),
            });
        }

        self.current_state = transition.target_state();
        Ok(self.current_state)
    }

    /// Apply a transition with role check
    pub fn transition_with_role(&mut self, transition: FileShareTransition, role: &str) -> Result<FileShareState, StateMachineError> {
        // Check basic transition validity first
        if !self.can_transition(transition) {
            return Err(StateMachineError::TransitionNotAllowed {
                transition: transition.to_string(),
                from: self.current_state.to_string(),
            });
        }

        // Check role authorization
        if !self.can_transition_with_role(transition, role) {
            return Err(StateMachineError::RoleNotAuthorized {
                role: role.to_string(),
                transition: transition.to_string(),
            });
        }

        self.current_state = transition.target_state();
        Ok(self.current_state)
    }

    /// Get all available transitions from the current state
    pub fn available_transitions(&self) -> Vec<FileShareTransition> {
        FileShareTransition::all()
            .into_iter()
            .filter(|t| self.can_transition(*t))
            .collect()
    }

    /// Get all available transitions for a given role
    pub fn available_transitions_for_role(&self, role: &str) -> Vec<FileShareTransition> {
        FileShareTransition::all()
            .into_iter()
            .filter(|t| self.can_transition_with_role(*t, role))
            .collect()
    }

    /// Attempt to transition directly to a target state.
    ///
    /// Finds any transition that leads to the target state and applies it.
    /// Returns Err if no valid transition leads from current state to target.
    pub fn transition_to_state(&mut self, target: FileShareState) -> Result<FileShareState, StateMachineError> {
        let valid = FileShareTransition::all().into_iter()
            .filter(|t| self.can_transition(*t))
            .find(|t| t.target_state() == target);
        match valid {
            Some(t) => self.transition(t),
            None => Err(StateMachineError::TransitionNotAllowed {
                transition: target.to_string(),
                from: self.current_state.to_string(),
            }),
        }
    }
}

impl Default for FileShareStateMachine {
    fn default() -> Self {
        Self::new()
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_initial_state() {
        let sm = FileShareStateMachine::new();
        assert_eq!(sm.current_state(), FileShareState::Active);
        assert!(sm.current_state().is_initial());
    }

    #[test]
    fn test_valid_transition() {
        let mut sm = FileShareStateMachine::from_state(FileShareState::Active);
        assert!(sm.can_transition(FileShareTransition::Expire));
        let result = sm.transition(FileShareTransition::Expire);
        assert!(result.is_ok());
        assert_eq!(sm.current_state(), FileShareState::Expired);
    }

    #[test]
    fn test_invalid_transition() {
        let mut sm = FileShareStateMachine::from_state(FileShareState::Inactive);
        // Expire is not valid from Inactive state
        let result = sm.transition(FileShareTransition::Expire);
        assert!(result.is_err());
    }

    #[test]
    fn test_state_parsing() {
        let state: FileShareState = "active".parse().unwrap();
        assert_eq!(state, FileShareState::Active);
    }

    #[test]
    fn test_available_transitions() {
        let sm = FileShareStateMachine::new();
        let available = sm.available_transitions();
        // Should have at least some transitions available from initial state
        assert!(!available.is_empty() || sm.current_state().is_final());
    }
}