use either::Either;
use hir::ModuleDef;
use ide_db::text_edit::TextRange;
use ide_db::{
    FxHashSet,
    assists::AssistId,
    defs::Definition,
    helpers::mod_path_to_ast,
    imports::insert_use::{ImportScope, insert_use},
    search::{FileReference, UsageSearchResult},
    source_change::SourceChangeBuilder,
};
use itertools::Itertools;
use syntax::ast::edit::AstNodeEdit;
use syntax::{
    AstNode, NodeOrToken, SyntaxKind, SyntaxNode, T,
    ast::{self, HasName, edit::IndentLevel, make},
};

use crate::{
    assist_context::{AssistContext, Assists},
    utils,
};

// Assist: convert_bool_to_enum
//
// This converts boolean local variables, fields, constants, and statics into a new
// enum with two variants `Bool::True` and `Bool::False`, as well as replacing
// all assignments with the variants and replacing all usages with `== Bool::True` or
// `== Bool::False`.
//
// ```
// fn main() {
//     let $0bool = true;
//
//     if bool {
//         println!("foo");
//     }
// }
// ```
// ->
// ```
// #[derive(PartialEq, Eq)]
// enum Bool { True, False }
//
// fn main() {
//     let bool = Bool::True;
//
//     if bool == Bool::True {
//         println!("foo");
//     }
// }
// ```
pub(crate) fn convert_bool_to_enum(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
    let BoolNodeData { target_node, name, ty_annotation, initializer, definition } =
        find_bool_node(ctx)?;
    let target_module = ctx.sema.scope(&target_node)?.module().nearest_non_block_module(ctx.db());

    let target = name.syntax().text_range();
    acc.add(
        AssistId::refactor_rewrite("convert_bool_to_enum"),
        "Convert boolean to enum",
        target,
        |edit| {
            if let Some(ty) = &ty_annotation {
                cov_mark::hit!(replaces_ty_annotation);
                edit.replace(ty.syntax().text_range(), "Bool");
            }

            if let Some(initializer) = initializer {
                replace_bool_expr(edit, initializer);
            }

            let usages = definition.usages(&ctx.sema).all();
            add_enum_def(edit, ctx, &usages, target_node, &target_module);
            let mut delayed_mutations = Vec::new();
            replace_usages(edit, ctx, usages, definition, &target_module, &mut delayed_mutations);
            for (scope, path) in delayed_mutations {
                insert_use(&scope, path, &ctx.config.insert_use);
            }
        },
    )
}

struct BoolNodeData {
    target_node: SyntaxNode,
    name: ast::Name,
    ty_annotation: Option<ast::Type>,
    initializer: Option<ast::Expr>,
    definition: Definition,
}

/// Attempts to find an appropriate node to apply the action to.
fn find_bool_node(ctx: &AssistContext<'_>) -> Option<BoolNodeData> {
    let name = ctx.find_node_at_offset::<ast::Name>()?;

    if let Some(ident_pat) = name.syntax().parent().and_then(ast::IdentPat::cast) {
        let def = ctx.sema.to_def(&ident_pat)?;
        if !def.ty(ctx.db()).is_bool() {
            cov_mark::hit!(not_applicable_non_bool_local);
            return None;
        }

        let local_definition = Definition::Local(def);
        match ident_pat.syntax().parent().and_then(Either::<ast::Param, ast::LetStmt>::cast)? {
            Either::Left(param) => Some(BoolNodeData {
                target_node: param.syntax().clone(),
                name,
                ty_annotation: param.ty(),
                initializer: None,
                definition: local_definition,
            }),
            Either::Right(let_stmt) => Some(BoolNodeData {
                target_node: let_stmt.syntax().clone(),
                name,
                ty_annotation: let_stmt.ty(),
                initializer: let_stmt.initializer(),
                definition: local_definition,
            }),
        }
    } else if let Some(const_) = name.syntax().parent().and_then(ast::Const::cast) {
        let def = ctx.sema.to_def(&const_)?;
        if !def.ty(ctx.db()).is_bool() {
            cov_mark::hit!(not_applicable_non_bool_const);
            return None;
        }

        Some(BoolNodeData {
            target_node: const_.syntax().clone(),
            name,
            ty_annotation: const_.ty(),
            initializer: const_.body(),
            definition: Definition::Const(def),
        })
    } else if let Some(static_) = name.syntax().parent().and_then(ast::Static::cast) {
        let def = ctx.sema.to_def(&static_)?;
        if !def.ty(ctx.db()).is_bool() {
            cov_mark::hit!(not_applicable_non_bool_static);
            return None;
        }

        Some(BoolNodeData {
            target_node: static_.syntax().clone(),
            name,
            ty_annotation: static_.ty(),
            initializer: static_.body(),
            definition: Definition::Static(def),
        })
    } else {
        let field = name.syntax().parent().and_then(ast::RecordField::cast)?;
        if field.name()? != name {
            return None;
        }

        let adt = field.syntax().ancestors().find_map(ast::Adt::cast)?;
        let def = ctx.sema.to_def(&field)?;
        if !def.ty(ctx.db()).is_bool() {
            cov_mark::hit!(not_applicable_non_bool_field);
            return None;
        }
        Some(BoolNodeData {
            target_node: adt.syntax().clone(),
            name,
            ty_annotation: field.ty(),
            initializer: None,
            definition: Definition::Field(def),
        })
    }
}

fn replace_bool_expr(edit: &mut SourceChangeBuilder, expr: ast::Expr) {
    let expr_range = expr.syntax().text_range();
    let enum_expr = bool_expr_to_enum_expr(expr);
    edit.replace(expr_range, enum_expr.syntax().text())
}

/// Converts an expression of type `bool` to one of the new enum type.
fn bool_expr_to_enum_expr(expr: ast::Expr) -> ast::Expr {
    let true_expr = make::expr_path(make::path_from_text("Bool::True"));
    let false_expr = make::expr_path(make::path_from_text("Bool::False"));

    if let ast::Expr::Literal(literal) = &expr {
        match literal.kind() {
            ast::LiteralKind::Bool(true) => true_expr,
            ast::LiteralKind::Bool(false) => false_expr,
            _ => expr,
        }
    } else {
        make::expr_if(
            expr,
            make::tail_only_block_expr(true_expr),
            Some(ast::ElseBranch::Block(make::tail_only_block_expr(false_expr))),
        )
        .into()
    }
}

/// Replaces all usages of the target identifier, both when read and written to.
fn replace_usages(
    edit: &mut SourceChangeBuilder,
    ctx: &AssistContext<'_>,
    usages: UsageSearchResult,
    target_definition: Definition,
    target_module: &hir::Module,
    delayed_mutations: &mut Vec<(ImportScope, ast::Path)>,
) {
    for (file_id, references) in usages {
        edit.edit_file(file_id.file_id(ctx.db()));

        let refs_with_imports = augment_references_with_imports(ctx, references, target_module);

        refs_with_imports.into_iter().rev().for_each(
            |FileReferenceWithImport { range, name, import_data }| {
                // replace the usages in patterns and expressions
                if let Some(ident_pat) = name.syntax().ancestors().find_map(ast::IdentPat::cast) {
                    cov_mark::hit!(replaces_record_pat_shorthand);

                    let definition = ctx.sema.to_def(&ident_pat).map(Definition::Local);
                    if let Some(def) = definition {
                        replace_usages(
                            edit,
                            ctx,
                            def.usages(&ctx.sema).all(),
                            target_definition,
                            target_module,
                            delayed_mutations,
                        )
                    }
                } else if let Some(initializer) = find_assignment_usage(&name) {
                    cov_mark::hit!(replaces_assignment);

                    replace_bool_expr(edit, initializer);
                } else if let Some((prefix_expr, inner_expr)) = find_negated_usage(&name) {
                    cov_mark::hit!(replaces_negation);

                    edit.replace(
                        prefix_expr.syntax().text_range(),
                        format!("{inner_expr} == Bool::False"),
                    );
                } else if let Some((record_field, initializer)) = name
                    .as_name_ref()
                    .and_then(ast::RecordExprField::for_field_name)
                    .and_then(|record_field| ctx.sema.resolve_record_field(&record_field))
                    .and_then(|(got_field, _, _)| {
                        find_record_expr_usage(&name, got_field, target_definition)
                    })
                {
                    cov_mark::hit!(replaces_record_expr);

                    let enum_expr = bool_expr_to_enum_expr(initializer);
                    utils::replace_record_field_expr(ctx, edit, record_field, enum_expr);
                } else if let Some(pat) = find_record_pat_field_usage(&name) {
                    match pat {
                        ast::Pat::IdentPat(ident_pat) => {
                            cov_mark::hit!(replaces_record_pat);

                            let definition = ctx.sema.to_def(&ident_pat).map(Definition::Local);
                            if let Some(def) = definition {
                                replace_usages(
                                    edit,
                                    ctx,
                                    def.usages(&ctx.sema).all(),
                                    target_definition,
                                    target_module,
                                    delayed_mutations,
                                )
                            }
                        }
                        ast::Pat::LiteralPat(literal_pat) => {
                            cov_mark::hit!(replaces_literal_pat);

                            if let Some(expr) = literal_pat.literal().and_then(|literal| {
                                literal.syntax().ancestors().find_map(ast::Expr::cast)
                            }) {
                                replace_bool_expr(edit, expr);
                            }
                        }
                        _ => (),
                    }
                } else if let Some((ty_annotation, initializer)) = find_assoc_const_usage(&name) {
                    edit.replace(ty_annotation.syntax().text_range(), "Bool");
                    replace_bool_expr(edit, initializer);
                } else if let Some(receiver) = find_method_call_expr_usage(&name) {
                    edit.replace(
                        receiver.syntax().text_range(),
                        format!("({receiver} == Bool::True)"),
                    );
                } else if name.syntax().ancestors().find_map(ast::UseTree::cast).is_none() {
                    // for any other usage in an expression, replace it with a check that it is the true variant
                    if let Some((record_field, expr)) =
                        name.as_name_ref().and_then(ast::RecordExprField::for_field_name).and_then(
                            |record_field| record_field.expr().map(|expr| (record_field, expr)),
                        )
                    {
                        utils::replace_record_field_expr(
                            ctx,
                            edit,
                            record_field,
                            make::expr_bin_op(
                                expr,
                                ast::BinaryOp::CmpOp(ast::CmpOp::Eq { negated: false }),
                                make::expr_path(make::path_from_text("Bool::True")),
                            ),
                        );
                    } else {
                        edit.replace(range, format!("{} == Bool::True", name.text()));
                    }
                }

                // add imports across modules where needed
                if let Some((scope, path)) = import_data {
                    let scope = edit.make_import_scope_mut(scope);
                    delayed_mutations.push((scope, path));
                }
            },
        )
    }
}

struct FileReferenceWithImport {
    range: TextRange,
    name: ast::NameLike,
    import_data: Option<(ImportScope, ast::Path)>,
}

fn augment_references_with_imports(
    ctx: &AssistContext<'_>,
    references: Vec<FileReference>,
    target_module: &hir::Module,
) -> Vec<FileReferenceWithImport> {
    let mut visited_modules = FxHashSet::default();

    let edition = target_module.krate(ctx.db()).edition(ctx.db());
    references
        .into_iter()
        .filter_map(|FileReference { range, name, .. }| {
            let name = name.into_name_like()?;
            ctx.sema.scope(name.syntax()).map(|scope| (range, name, scope.module()))
        })
        .map(|(range, name, ref_module)| {
            // if the referenced module is not the same as the target one and has not been seen before, add an import
            let import_data = if ref_module.nearest_non_block_module(ctx.db()) != *target_module
                && !visited_modules.contains(&ref_module)
            {
                visited_modules.insert(ref_module);

                ImportScope::find_insert_use_container(name.syntax(), &ctx.sema).and_then(
                    |import_scope| {
                        let cfg = ctx.config.find_path_config(
                            ctx.sema.is_nightly(target_module.krate(ctx.sema.db)),
                        );
                        let path = ref_module
                            .find_use_path(
                                ctx.sema.db,
                                ModuleDef::Module(*target_module),
                                ctx.config.insert_use.prefix_kind,
                                cfg,
                            )
                            .map(|mod_path| {
                                make::path_concat(
                                    mod_path_to_ast(&mod_path, edition),
                                    make::path_from_text("Bool"),
                                )
                            })?;

                        Some((import_scope, path))
                    },
                )
            } else {
                None
            };

            FileReferenceWithImport { range, name, import_data }
        })
        .collect()
}

fn find_assignment_usage(name: &ast::NameLike) -> Option<ast::Expr> {
    let bin_expr = name.syntax().ancestors().find_map(ast::BinExpr::cast)?;

    if !bin_expr.lhs()?.syntax().descendants().contains(name.syntax()) {
        cov_mark::hit!(dont_assign_incorrect_ref);
        return None;
    }

    if let Some(ast::BinaryOp::Assignment { op: None }) = bin_expr.op_kind() {
        bin_expr.rhs()
    } else {
        None
    }
}

fn find_negated_usage(name: &ast::NameLike) -> Option<(ast::PrefixExpr, ast::Expr)> {
    let prefix_expr = name.syntax().ancestors().find_map(ast::PrefixExpr::cast)?;

    if !matches!(prefix_expr.expr()?, ast::Expr::PathExpr(_) | ast::Expr::FieldExpr(_)) {
        cov_mark::hit!(dont_overwrite_expression_inside_negation);
        return None;
    }

    if let Some(ast::UnaryOp::Not) = prefix_expr.op_kind() {
        let inner_expr = prefix_expr.expr()?;
        Some((prefix_expr, inner_expr))
    } else {
        None
    }
}

fn find_record_expr_usage(
    name: &ast::NameLike,
    got_field: hir::Field,
    target_definition: Definition,
) -> Option<(ast::RecordExprField, ast::Expr)> {
    let name_ref = name.as_name_ref()?;
    let record_field = ast::RecordExprField::for_field_name(name_ref)?;
    let initializer = record_field.expr()?;

    match target_definition {
        Definition::Field(expected_field) if got_field == expected_field => {
            Some((record_field, initializer))
        }
        _ => None,
    }
}

fn find_record_pat_field_usage(name: &ast::NameLike) -> Option<ast::Pat> {
    let record_pat_field = name.syntax().parent().and_then(ast::RecordPatField::cast)?;
    let pat = record_pat_field.pat()?;

    match pat {
        ast::Pat::IdentPat(_) | ast::Pat::LiteralPat(_) | ast::Pat::WildcardPat(_) => Some(pat),
        _ => None,
    }
}

fn find_assoc_const_usage(name: &ast::NameLike) -> Option<(ast::Type, ast::Expr)> {
    let const_ = name.syntax().parent().and_then(ast::Const::cast)?;
    const_.syntax().parent().and_then(ast::AssocItemList::cast)?;

    Some((const_.ty()?, const_.body()?))
}

fn find_method_call_expr_usage(name: &ast::NameLike) -> Option<ast::Expr> {
    let method_call = name.syntax().ancestors().find_map(ast::MethodCallExpr::cast)?;
    let receiver = method_call.receiver()?;

    if !receiver.syntax().descendants().contains(name.syntax()) {
        return None;
    }

    Some(receiver)
}

/// Adds the definition of the new enum before the target node.
fn add_enum_def(
    edit: &mut SourceChangeBuilder,
    ctx: &AssistContext<'_>,
    usages: &UsageSearchResult,
    target_node: SyntaxNode,
    target_module: &hir::Module,
) -> Option<()> {
    let insert_before = node_to_insert_before(target_node);

    if ctx
        .sema
        .scope(&insert_before)?
        .module()
        .scope(ctx.db(), Some(*target_module))
        .iter()
        .any(|(name, _)| name.as_str() == "Bool")
    {
        return None;
    }

    let make_enum_pub = usages
        .iter()
        .flat_map(|(_, refs)| refs)
        .filter_map(|FileReference { name, .. }| {
            let name = name.clone().into_name_like()?;
            ctx.sema.scope(name.syntax()).map(|scope| scope.module())
        })
        .any(|module| module.nearest_non_block_module(ctx.db()) != *target_module);

    let indent = IndentLevel::from_node(&insert_before);
    let enum_def = make_bool_enum(make_enum_pub).reset_indent().indent(indent);

    edit.insert(
        insert_before.text_range().start(),
        format!("{}\n\n{indent}", enum_def.syntax().text()),
    );

    Some(())
}

/// Finds where to put the new enum definition.
/// Tries to find the ast node at the nearest module or at top-level, otherwise just
/// returns the input node.
fn node_to_insert_before(target_node: SyntaxNode) -> SyntaxNode {
    target_node
        .ancestors()
        .take_while(|it| !matches!(it.kind(), SyntaxKind::MODULE | SyntaxKind::SOURCE_FILE))
        .filter(|it| ast::Item::can_cast(it.kind()))
        .last()
        .unwrap_or(target_node)
}

fn make_bool_enum(make_pub: bool) -> ast::Enum {
    let derive_eq = make::attr_outer(make::meta_token_tree(
        make::ext::ident_path("derive"),
        make::token_tree(
            T!['('],
            vec![
                NodeOrToken::Token(make::tokens::ident("PartialEq")),
                NodeOrToken::Token(make::token(T![,])),
                NodeOrToken::Token(make::tokens::single_space()),
                NodeOrToken::Token(make::tokens::ident("Eq")),
            ],
        ),
    ));
    make::enum_(
        [derive_eq],
        if make_pub { Some(make::visibility_pub()) } else { None },
        make::name("Bool"),
        None,
        None,
        make::variant_list(vec![
            make::variant(None, make::name("True"), None, None),
            make::variant(None, make::name("False"), None, None),
        ]),
    )
    .clone_for_update()
}

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

    use crate::tests::{check_assist, check_assist_not_applicable};

    #[test]
    fn parameter_with_first_param_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn function($0foo: bool, bar: bool) {
    if foo {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn function(foo: Bool, bar: bool) {
    if foo == Bool::True {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn no_duplicate_enums() {
        check_assist(
            convert_bool_to_enum,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn function(foo: bool, $0bar: bool) {
    if bar {
        println!("bar");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn function(foo: bool, bar: Bool) {
    if bar == Bool::True {
        println!("bar");
    }
}
"#,
        )
    }

    #[test]
    fn parameter_with_last_param_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn function(foo: bool, $0bar: bool) {
    if bar {
        println!("bar");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn function(foo: bool, bar: Bool) {
    if bar == Bool::True {
        println!("bar");
    }
}
"#,
        )
    }

    #[test]
    fn parameter_with_middle_param_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn function(foo: bool, $0bar: bool, baz: bool) {
    if bar {
        println!("bar");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn function(foo: bool, bar: Bool, baz: bool) {
    if bar == Bool::True {
        println!("bar");
    }
}
"#,
        )
    }

    #[test]
    fn parameter_with_closure_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let foo = |$0bar: bool| bar;
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo = |bar: Bool| bar == Bool::True;
}
"#,
        )
    }

    #[test]
    fn local_variable_with_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo = true;

    if foo {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo = Bool::True;

    if foo == Bool::True {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn local_variable_with_usage_negated() {
        cov_mark::check!(replaces_negation);
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo = true;

    if !foo {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo = Bool::True;

    if foo == Bool::False {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn local_variable_with_type_annotation() {
        cov_mark::check!(replaces_ty_annotation);
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo: bool = false;
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo: Bool = Bool::False;
}
"#,
        )
    }

    #[test]
    fn local_variable_with_non_literal_initializer() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo = 1 == 2;
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo = if 1 == 2 { Bool::True } else { Bool::False };
}
"#,
        )
    }

    #[test]
    fn local_variable_binexpr_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo = false;
    let bar = true;

    if !foo && bar {
        println!("foobar");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo = Bool::False;
    let bar = true;

    if foo == Bool::False && bar {
        println!("foobar");
    }
}
"#,
        )
    }

    #[test]
    fn local_variable_unop_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo = true;

    if *&foo {
        println!("foobar");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo = Bool::True;

    if *&foo == Bool::True {
        println!("foobar");
    }
}
"#,
        )
    }

    #[test]
    fn local_variable_assigned_later() {
        cov_mark::check!(replaces_assignment);
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo: bool;
    foo = true;
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo: Bool;
    foo = Bool::True;
}
"#,
        )
    }

    #[test]
    fn local_variable_does_not_apply_recursively() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo = true;
    let bar = !foo;

    if bar {
        println!("bar");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo = Bool::True;
    let bar = foo == Bool::False;

    if bar {
        println!("bar");
    }
}
"#,
        )
    }

    #[test]
    fn local_variable_nested_in_negation() {
        cov_mark::check!(dont_overwrite_expression_inside_negation);
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    if !"foo".chars().any(|c| {
        let $0foo = true;
        foo
    }) {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    if !"foo".chars().any(|c| {
        let foo = Bool::True;
        foo == Bool::True
    }) {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn local_variable_non_bool() {
        cov_mark::check!(not_applicable_non_bool_local);
        check_assist_not_applicable(
            convert_bool_to_enum,
            r#"
fn main() {
    let $0foo = 1;
}
"#,
        )
    }

    #[test]
    fn local_variable_cursor_not_on_ident() {
        check_assist_not_applicable(
            convert_bool_to_enum,
            r#"
fn main() {
    let foo = $0true;
}
"#,
        )
    }

    #[test]
    fn local_variable_non_ident_pat() {
        check_assist_not_applicable(
            convert_bool_to_enum,
            r#"
fn main() {
    let ($0foo, bar) = (true, false);
}
"#,
        )
    }

    #[test]
    fn local_var_init_struct_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
struct Foo {
    foo: bool,
}

fn main() {
    let $0foo = true;
    let s = Foo { foo };
}
"#,
            r#"
struct Foo {
    foo: bool,
}

#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn main() {
    let foo = Bool::True;
    let s = Foo { foo: foo == Bool::True };
}
"#,
        )
    }

    #[test]
    fn local_var_init_struct_usage_in_macro() {
        check_assist(
            convert_bool_to_enum,
            r#"
struct Struct {
    boolean: bool,
}

macro_rules! identity {
    ($body:expr) => {
        $body
    }
}

fn new() -> Struct {
    let $0boolean = true;
    identity![Struct { boolean }]
}
"#,
            r#"
struct Struct {
    boolean: bool,
}

macro_rules! identity {
    ($body:expr) => {
        $body
    }
}

#[derive(PartialEq, Eq)]
enum Bool { True, False }

fn new() -> Struct {
    let boolean = Bool::True;
    identity![Struct { boolean: boolean == Bool::True }]
}
"#,
        )
    }

    #[test]
    fn field_struct_basic() {
        cov_mark::check!(replaces_record_expr);
        check_assist(
            convert_bool_to_enum,
            r#"
struct Foo {
    $0bar: bool,
    baz: bool,
}

fn main() {
    let foo = Foo { bar: true, baz: false };

    if foo.bar {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

struct Foo {
    bar: Bool,
    baz: bool,
}

fn main() {
    let foo = Foo { bar: Bool::True, baz: false };

    if foo.bar == Bool::True {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn field_enum_basic() {
        cov_mark::check!(replaces_record_pat);
        check_assist(
            convert_bool_to_enum,
            r#"
enum Foo {
    Foo,
    Bar { $0bar: bool },
}

fn main() {
    let foo = Foo::Bar { bar: true };

    if let Foo::Bar { bar: baz } = foo {
        if baz {
            println!("foo");
        }
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

enum Foo {
    Foo,
    Bar { bar: Bool },
}

fn main() {
    let foo = Foo::Bar { bar: Bool::True };

    if let Foo::Bar { bar: baz } = foo {
        if baz == Bool::True {
            println!("foo");
        }
    }
}
"#,
        )
    }

    #[test]
    fn field_enum_cross_file() {
        // FIXME: The import is missing
        check_assist(
            convert_bool_to_enum,
            r#"
//- /foo.rs
pub enum Foo {
    Foo,
    Bar { $0bar: bool },
}

fn foo() {
    let foo = Foo::Bar { bar: true };
}

//- /main.rs
use foo::Foo;

mod foo;

fn main() {
    let foo = Foo::Bar { bar: false };
}
"#,
            r#"
//- /foo.rs
#[derive(PartialEq, Eq)]
pub enum Bool { True, False }

pub enum Foo {
    Foo,
    Bar { bar: Bool },
}

fn foo() {
    let foo = Foo::Bar { bar: Bool::True };
}

//- /main.rs
use foo::{Bool, Foo};

mod foo;

fn main() {
    let foo = Foo::Bar { bar: Bool::False };
}
"#,
        )
    }

    #[test]
    fn field_enum_shorthand() {
        cov_mark::check!(replaces_record_pat_shorthand);
        check_assist(
            convert_bool_to_enum,
            r#"
enum Foo {
    Foo,
    Bar { $0bar: bool },
}

fn main() {
    let foo = Foo::Bar { bar: true };

    match foo {
        Foo::Bar { bar } => {
            if bar {
                println!("foo");
            }
        }
        _ => (),
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

enum Foo {
    Foo,
    Bar { bar: Bool },
}

fn main() {
    let foo = Foo::Bar { bar: Bool::True };

    match foo {
        Foo::Bar { bar } => {
            if bar == Bool::True {
                println!("foo");
            }
        }
        _ => (),
    }
}
"#,
        )
    }

    #[test]
    fn field_enum_replaces_literal_patterns() {
        cov_mark::check!(replaces_literal_pat);
        check_assist(
            convert_bool_to_enum,
            r#"
enum Foo {
    Foo,
    Bar { $0bar: bool },
}

fn main() {
    let foo = Foo::Bar { bar: true };

    if let Foo::Bar { bar: true } = foo {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

enum Foo {
    Foo,
    Bar { bar: Bool },
}

fn main() {
    let foo = Foo::Bar { bar: Bool::True };

    if let Foo::Bar { bar: Bool::True } = foo {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn field_enum_keeps_wildcard_patterns() {
        check_assist(
            convert_bool_to_enum,
            r#"
enum Foo {
    Foo,
    Bar { $0bar: bool },
}

fn main() {
    let foo = Foo::Bar { bar: true };

    if let Foo::Bar { bar: _ } = foo {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

enum Foo {
    Foo,
    Bar { bar: Bool },
}

fn main() {
    let foo = Foo::Bar { bar: Bool::True };

    if let Foo::Bar { bar: _ } = foo {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn field_union_basic() {
        check_assist(
            convert_bool_to_enum,
            r#"
union Foo {
    $0foo: bool,
    bar: usize,
}

fn main() {
    let foo = Foo { foo: true };

    if unsafe { foo.foo } {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

union Foo {
    foo: Bool,
    bar: usize,
}

fn main() {
    let foo = Foo { foo: Bool::True };

    if unsafe { foo.foo == Bool::True } {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn field_negated() {
        check_assist(
            convert_bool_to_enum,
            r#"
struct Foo {
    $0bar: bool,
}

fn main() {
    let foo = Foo { bar: false };

    if !foo.bar {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

struct Foo {
    bar: Bool,
}

fn main() {
    let foo = Foo { bar: Bool::False };

    if foo.bar == Bool::False {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn field_in_mod_properly_indented() {
        check_assist(
            convert_bool_to_enum,
            r#"
mod foo {
    struct Bar {
        $0baz: bool,
    }

    impl Bar {
        fn new(baz: bool) -> Self {
            Self { baz }
        }
    }
}
"#,
            r#"
mod foo {
    #[derive(PartialEq, Eq)]
    enum Bool { True, False }

    struct Bar {
        baz: Bool,
    }

    impl Bar {
        fn new(baz: bool) -> Self {
            Self { baz: if baz { Bool::True } else { Bool::False } }
        }
    }
}
"#,
        )
    }

    #[test]
    fn field_multiple_initializations() {
        check_assist(
            convert_bool_to_enum,
            r#"
struct Foo {
    $0bar: bool,
    baz: bool,
}

fn main() {
    let foo1 = Foo { bar: true, baz: false };
    let foo2 = Foo { bar: false, baz: false };

    if foo1.bar && foo2.bar {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

struct Foo {
    bar: Bool,
    baz: bool,
}

fn main() {
    let foo1 = Foo { bar: Bool::True, baz: false };
    let foo2 = Foo { bar: Bool::False, baz: false };

    if foo1.bar == Bool::True && foo2.bar == Bool::True {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn field_assigned_to_another() {
        cov_mark::check!(dont_assign_incorrect_ref);
        check_assist(
            convert_bool_to_enum,
            r#"
struct Foo {
    $0foo: bool,
}

struct Bar {
    bar: bool,
}

fn main() {
    let foo = Foo { foo: true };
    let mut bar = Bar { bar: true };

    bar.bar = foo.foo;
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

struct Foo {
    foo: Bool,
}

struct Bar {
    bar: bool,
}

fn main() {
    let foo = Foo { foo: Bool::True };
    let mut bar = Bar { bar: true };

    bar.bar = foo.foo == Bool::True;
}
"#,
        )
    }

    #[test]
    fn field_initialized_with_other() {
        check_assist(
            convert_bool_to_enum,
            r#"
struct Foo {
    $0foo: bool,
}

struct Bar {
    bar: bool,
}

fn main() {
    let foo = Foo { foo: true };
    let bar = Bar { bar: foo.foo };
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

struct Foo {
    foo: Bool,
}

struct Bar {
    bar: bool,
}

fn main() {
    let foo = Foo { foo: Bool::True };
    let bar = Bar { bar: foo.foo == Bool::True };
}
"#,
        )
    }

    #[test]
    fn field_method_chain_usage() {
        check_assist(
            convert_bool_to_enum,
            r#"
struct Foo {
    $0bool: bool,
}

fn main() {
    let foo = Foo { bool: true };

    foo.bool.then(|| 2);
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

struct Foo {
    bool: Bool,
}

fn main() {
    let foo = Foo { bool: Bool::True };

    (foo.bool == Bool::True).then(|| 2);
}
"#,
        )
    }

    #[test]
    fn field_in_macro() {
        check_assist(
            convert_bool_to_enum,
            r#"
struct Struct {
    $0boolean: bool,
}

fn boolean(x: Struct) {
    let Struct { boolean } = x;
}

macro_rules! identity { ($body:expr) => { $body } }

fn new() -> Struct {
    identity!(Struct { boolean: true })
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

struct Struct {
    boolean: Bool,
}

fn boolean(x: Struct) {
    let Struct { boolean } = x;
}

macro_rules! identity { ($body:expr) => { $body } }

fn new() -> Struct {
    identity!(Struct { boolean: Bool::True })
}
"#,
        )
    }

    #[test]
    fn field_non_bool() {
        cov_mark::check!(not_applicable_non_bool_field);
        check_assist_not_applicable(
            convert_bool_to_enum,
            r#"
struct Foo {
    $0bar: usize,
}

fn main() {
    let foo = Foo { bar: 1 };
}
"#,
        )
    }

    #[test]
    fn const_basic() {
        check_assist(
            convert_bool_to_enum,
            r#"
const $0FOO: bool = false;

fn main() {
    if FOO {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

const FOO: Bool = Bool::False;

fn main() {
    if FOO == Bool::True {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn const_in_module() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    if foo::FOO {
        println!("foo");
    }
}

mod foo {
    pub const $0FOO: bool = true;
}
"#,
            r#"
use foo::Bool;

fn main() {
    if foo::FOO == Bool::True {
        println!("foo");
    }
}

mod foo {
    #[derive(PartialEq, Eq)]
    pub enum Bool { True, False }

    pub const FOO: Bool = Bool::True;
}
"#,
        )
    }

    #[test]
    fn const_in_module_with_import() {
        check_assist(
            convert_bool_to_enum,
            r#"
fn main() {
    use foo::FOO;

    if FOO {
        println!("foo");
    }
}

mod foo {
    pub const $0FOO: bool = true;
}
"#,
            r#"
use foo::Bool;

fn main() {
    use foo::FOO;

    if FOO == Bool::True {
        println!("foo");
    }
}

mod foo {
    #[derive(PartialEq, Eq)]
    pub enum Bool { True, False }

    pub const FOO: Bool = Bool::True;
}
"#,
        )
    }

    #[test]
    fn const_cross_file() {
        check_assist(
            convert_bool_to_enum,
            r#"
//- /main.rs
mod foo;

fn main() {
    if foo::FOO {
        println!("foo");
    }
}

//- /foo.rs
pub const $0FOO: bool = true;
"#,
            r#"
//- /main.rs
use foo::Bool;

mod foo;

fn main() {
    if foo::FOO == Bool::True {
        println!("foo");
    }
}

//- /foo.rs
#[derive(PartialEq, Eq)]
pub enum Bool { True, False }

pub const FOO: Bool = Bool::True;
"#,
        )
    }

    #[test]
    fn const_cross_file_and_module() {
        check_assist(
            convert_bool_to_enum,
            r#"
//- /main.rs
mod foo;

fn main() {
    use foo::bar;

    if bar::BAR {
        println!("foo");
    }
}

//- /foo.rs
pub mod bar {
    pub const $0BAR: bool = false;
}
"#,
            r#"
//- /main.rs
use foo::bar::Bool;

mod foo;

fn main() {
    use foo::bar;

    if bar::BAR == Bool::True {
        println!("foo");
    }
}

//- /foo.rs
pub mod bar {
    #[derive(PartialEq, Eq)]
    pub enum Bool { True, False }

    pub const BAR: Bool = Bool::False;
}
"#,
        )
    }

    #[test]
    fn const_in_impl_cross_file() {
        check_assist(
            convert_bool_to_enum,
            r#"
//- /main.rs
mod foo;

struct Foo;

impl Foo {
    pub const $0BOOL: bool = true;
}

//- /foo.rs
use crate::Foo;

fn foo() -> bool {
    Foo::BOOL
}
"#,
            r#"
//- /main.rs
mod foo;

struct Foo;

#[derive(PartialEq, Eq)]
pub enum Bool { True, False }

impl Foo {
    pub const BOOL: Bool = Bool::True;
}

//- /foo.rs
use crate::{Bool, Foo};

fn foo() -> bool {
    Foo::BOOL == Bool::True
}
"#,
        )
    }

    #[test]
    fn const_in_trait() {
        check_assist(
            convert_bool_to_enum,
            r#"
trait Foo {
    const $0BOOL: bool;
}

impl Foo for usize {
    const BOOL: bool = true;
}

fn main() {
    if <usize as Foo>::BOOL {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

trait Foo {
    const BOOL: Bool;
}

impl Foo for usize {
    const BOOL: Bool = Bool::True;
}

fn main() {
    if <usize as Foo>::BOOL == Bool::True {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn const_non_bool() {
        cov_mark::check!(not_applicable_non_bool_const);
        check_assist_not_applicable(
            convert_bool_to_enum,
            r#"
const $0FOO: &str = "foo";

fn main() {
    println!("{FOO}");
}
"#,
        )
    }

    #[test]
    fn static_basic() {
        check_assist(
            convert_bool_to_enum,
            r#"
static mut $0BOOL: bool = true;

fn main() {
    unsafe { BOOL = false };
    if unsafe { BOOL } {
        println!("foo");
    }
}
"#,
            r#"
#[derive(PartialEq, Eq)]
enum Bool { True, False }

static mut BOOL: Bool = Bool::True;

fn main() {
    unsafe { BOOL = Bool::False };
    if unsafe { BOOL == Bool::True } {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn static_non_bool() {
        cov_mark::check!(not_applicable_non_bool_static);
        check_assist_not_applicable(
            convert_bool_to_enum,
            r#"
static mut $0FOO: usize = 0;

fn main() {
    if unsafe { FOO } == 0 {
        println!("foo");
    }
}
"#,
        )
    }

    #[test]
    fn not_applicable_to_other_names() {
        check_assist_not_applicable(convert_bool_to_enum, "fn $0main() {}")
    }
}