1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146

//! This module defines the `Assist` data structure. The actual assist live in
//! the `ide_assists` downstream crate. We want to define the data structures in
//! this low-level crate though, because `ide_diagnostics` also need them
//! (fixits for diagnostics and assists are the same thing under the hood). We
//! want to compile `ide_assists` and `ide_diagnostics` in parallel though, so
//! we pull the common definitions upstream, to this crate.

use std::str::FromStr;

use syntax::TextRange;

use crate::{label::Label, source_change::SourceChange};

#[derive(Debug, Clone)]
pub struct Assist {
    pub id: AssistId,
    /// Short description of the assist, as shown in the UI.
    pub label: Label,
    pub group: Option<GroupLabel>,
    /// Target ranges are used to sort assists: the smaller the target range,
    /// the more specific assist is, and so it should be sorted first.
    pub target: TextRange,
    /// Computing source change sometimes is much more costly then computing the
    /// other fields. Additionally, the actual change is not required to show
    /// the lightbulb UI, it only is needed when the user tries to apply an
    /// assist. So, we compute it lazily: the API allow requesting assists with
    /// or without source change. We could (and in fact, used to) distinguish
    /// between resolved and unresolved assists at the type level, but this is
    /// cumbersome, especially if you want to embed an assist into another data
    /// structure, such as a diagnostic.
    pub source_change: Option<SourceChange>,
    /// The command to execute after the assist is applied.
    pub command: Option<Command>,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum Command {
    /// Show the parameter hints popup.
    TriggerParameterHints,
    /// Rename the just inserted item.
    Rename,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum AssistKind {
    // FIXME: does the None variant make sense? Probably not.
    None,

    QuickFix,
    Generate,
    Refactor,
    RefactorExtract,
    RefactorInline,
    RefactorRewrite,
}

impl AssistKind {
    pub fn contains(self, other: AssistKind) -> bool {
        if self == other {
            return true;
        }

        match self {
            AssistKind::None | AssistKind::Generate => true,
            AssistKind::Refactor => matches!(
                other,
                AssistKind::RefactorExtract
                    | AssistKind::RefactorInline
                    | AssistKind::RefactorRewrite
            ),
            _ => false,
        }
    }

    pub fn name(&self) -> &str {
        match self {
            AssistKind::None => "None",
            AssistKind::QuickFix => "QuickFix",
            AssistKind::Generate => "Generate",
            AssistKind::Refactor => "Refactor",
            AssistKind::RefactorExtract => "RefactorExtract",
            AssistKind::RefactorInline => "RefactorInline",
            AssistKind::RefactorRewrite => "RefactorRewrite",
        }
    }
}

impl FromStr for AssistKind {
    type Err = String;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        match s {
            "None" => Ok(AssistKind::None),
            "QuickFix" => Ok(AssistKind::QuickFix),
            "Generate" => Ok(AssistKind::Generate),
            "Refactor" => Ok(AssistKind::Refactor),
            "RefactorExtract" => Ok(AssistKind::RefactorExtract),
            "RefactorInline" => Ok(AssistKind::RefactorInline),
            "RefactorRewrite" => Ok(AssistKind::RefactorRewrite),
            unknown => Err(format!("Unknown AssistKind: '{unknown}'")),
        }
    }
}

/// Unique identifier of the assist, should not be shown to the user
/// directly.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct AssistId(pub &'static str, pub AssistKind);

/// A way to control how many assist to resolve during the assist resolution.
/// When an assist is resolved, its edits are calculated that might be costly to always do by default.
#[derive(Debug)]
pub enum AssistResolveStrategy {
    /// No assists should be resolved.
    None,
    /// All assists should be resolved.
    All,
    /// Only a certain assist should be resolved.
    Single(SingleResolve),
}

/// Hold the [`AssistId`] data of a certain assist to resolve.
/// The original id object cannot be used due to a `'static` lifetime
/// and the requirement to construct this struct dynamically during the resolve handling.
#[derive(Debug)]
pub struct SingleResolve {
    /// The id of the assist.
    pub assist_id: String,
    // The kind of the assist.
    pub assist_kind: AssistKind,
}

impl AssistResolveStrategy {
    pub fn should_resolve(&self, id: &AssistId) -> bool {
        match self {
            AssistResolveStrategy::None => false,
            AssistResolveStrategy::All => true,
            AssistResolveStrategy::Single(single_resolve) => {
                single_resolve.assist_id == id.0 && single_resolve.assist_kind == id.1
            }
        }
    }
}

#[derive(Clone, Debug)]
pub struct GroupLabel(pub String);