//! Common types for the [push notifications module][push]
//!
//! [push]: https://matrix.org/docs/spec/client_server/r0.6.1#id89

use serde::{Deserialize, Serialize};

mod action;
mod any_push_rule;
mod condition;

pub use self::{
    action::{Action, Tweak},
    any_push_rule::{AnyPushRule, MissingConditionsError, MissingPatternError},
    condition::{ComparisonOperator, PushCondition, RoomMemberCountIs},
};

/// A push ruleset scopes a set of rules according to some criteria.
///
/// For example, some rules may only be applied for messages from a particular sender, a particular
/// room, or by default. The push ruleset contains the entire set of scopes and rules.
///
/// To create an instance of this type, use its `Default` implementation and set the fields you
/// need.
#[derive(Clone, Debug, Default, Deserialize, Serialize)]
#[non_exhaustive]
pub struct Ruleset {
    /// These rules configure behavior for (unencrypted) messages that match certain patterns.
    pub content: Vec<PatternedPushRule>,

    /// These user-configured rules are given the highest priority.
    ///
    /// This field is named `override_` instead of `override` because the latter is a reserved
    /// keyword in Rust.
    #[serde(rename = "override")]
    pub override_: Vec<ConditionalPushRule>,

    /// These rules change the behavior of all messages for a given room.
    pub room: Vec<PushRule>,

    /// These rules configure notification behavior for messages from a specific Matrix user ID.
    pub sender: Vec<PushRule>,

    /// These rules are identical to override rules, but have a lower priority than `content`,
    /// `room` and `sender` rules.
    pub underride: Vec<ConditionalPushRule>,
}

/// A push rule is a single rule that states under what conditions an event should be passed onto a
/// push gateway and how the notification should be presented.
///
/// These rules are stored on the user's homeserver. They are manually configured by the user, who
/// can create and view them via the Client/Server API.
///
/// To create an instance of this type, first create a `PushRuleInit` and convert it via
/// `PushRule::from` / `.into()`.
#[derive(Clone, Debug, Deserialize, Serialize)]
#[non_exhaustive]
pub struct PushRule {
    /// Actions to determine if and how a notification is delivered for events matching this rule.
    pub actions: Vec<Action>,

    /// Whether this is a default rule, or has been set explicitly.
    pub default: bool,

    /// Whether the push rule is enabled or not.
    pub enabled: bool,

    /// The ID of this rule.
    pub rule_id: String,
}

/// Initial set of fields of `PushRule`.
///
/// This struct will not be updated even if additional fields are added to `PushRule` in a new
/// (non-breaking) release of the Matrix specification.
#[derive(Debug)]
pub struct PushRuleInit {
    /// Actions to determine if and how a notification is delivered for events matching this rule.
    pub actions: Vec<Action>,

    /// Whether this is a default rule, or has been set explicitly.
    pub default: bool,

    /// Whether the push rule is enabled or not.
    pub enabled: bool,

    /// The ID of this rule.
    pub rule_id: String,
}

impl From<PushRuleInit> for PushRule {
    fn from(init: PushRuleInit) -> Self {
        let PushRuleInit { actions, default, enabled, rule_id } = init;
        Self { actions, default, enabled, rule_id }
    }
}

/// Like `PushRule`, but with an additional `conditions` field.
///
/// Only applicable to underride and override rules.
///
/// To create an instance of this type, first create a `ConditionalPushRuleInit` and convert it via
/// `ConditionalPushRule::from` / `.into()`.
#[derive(Clone, Debug, Deserialize, Serialize)]
#[non_exhaustive]
pub struct ConditionalPushRule {
    /// Actions to determine if and how a notification is delivered for events matching this rule.
    pub actions: Vec<Action>,

    /// Whether this is a default rule, or has been set explicitly.
    pub default: bool,

    /// Whether the push rule is enabled or not.
    pub enabled: bool,

    /// The ID of this rule.
    pub rule_id: String,

    /// The conditions that must hold true for an event in order for a rule to be applied to an event.
    ///
    /// A rule with no conditions always matches.
    pub conditions: Vec<PushCondition>,
}

/// Initial set of fields of `ConditionalPushRule`.
///
/// This struct will not be updated even if additional fields are added to `ConditionalPushRule` in
/// a new (non-breaking) release of the Matrix specification.
#[derive(Debug)]
pub struct ConditionalPushRuleInit {
    /// Actions to determine if and how a notification is delivered for events matching this rule.
    pub actions: Vec<Action>,

    /// Whether this is a default rule, or has been set explicitly.
    pub default: bool,

    /// Whether the push rule is enabled or not.
    pub enabled: bool,

    /// The ID of this rule.
    pub rule_id: String,

    /// The conditions that must hold true for an event in order for a rule to be applied to an event.
    ///
    /// A rule with no conditions always matches.
    pub conditions: Vec<PushCondition>,
}

impl From<ConditionalPushRuleInit> for ConditionalPushRule {
    fn from(init: ConditionalPushRuleInit) -> Self {
        let ConditionalPushRuleInit { actions, default, enabled, rule_id, conditions } = init;
        Self { actions, default, enabled, rule_id, conditions }
    }
}

/// Like `PushRule`, but with an additional `pattern` field.
///
/// Only applicable to content rules.
///
/// To create an instance of this type, first create a `PatternedPushRuleInit` and convert it via
/// `PatternedPushRule::from` / `.into()`.
#[derive(Clone, Debug, Deserialize, Serialize)]
#[non_exhaustive]
pub struct PatternedPushRule {
    /// Actions to determine if and how a notification is delivered for events matching this rule.
    pub actions: Vec<Action>,

    /// Whether this is a default rule, or has been set explicitly.
    pub default: bool,

    /// Whether the push rule is enabled or not.
    pub enabled: bool,

    /// The ID of this rule.
    pub rule_id: String,

    /// The glob-style pattern to match against.
    pub pattern: String,
}

/// Initial set of fields of `PatterenedPushRule`.
///
/// This struct will not be updated even if additional fields are added to `PatterenedPushRule` in a new
/// (non-breaking) release of the Matrix specification.
#[derive(Debug)]
pub struct PatternedPushRuleInit {
    /// Actions to determine if and how a notification is delivered for events matching this rule.
    pub actions: Vec<Action>,

    /// Whether this is a default rule, or has been set explicitly.
    pub default: bool,

    /// Whether the push rule is enabled or not.
    pub enabled: bool,

    /// The ID of this rule.
    pub rule_id: String,

    /// The glob-style pattern to match against.
    pub pattern: String,
}

impl From<PatternedPushRuleInit> for PatternedPushRule {
    fn from(init: PatternedPushRuleInit) -> Self {
        let PatternedPushRuleInit { actions, default, enabled, rule_id, pattern } = init;
        Self { actions, default, enabled, rule_id, pattern }
    }
}