//! FIXME: write short doc here

use std::any::Any;

use ra_syntax::{ast, AstNode, AstPtr, SyntaxNodePtr};
use relative_path::RelativePathBuf;

use crate::{db::AstDatabase, HirFileId, Name, Source};

pub use hir_expand::diagnostics::{AstDiagnostic, Diagnostic, DiagnosticSink};

#[derive(Debug)]
pub struct NoSuchField {
    pub file: HirFileId,
    pub field: AstPtr<ast::RecordField>,
}

impl Diagnostic for NoSuchField {
    fn message(&self) -> String {
        "no such field".to_string()
    }

    fn source(&self) -> Source<SyntaxNodePtr> {
        Source { file_id: self.file, ast: self.field.into() }
    }

    fn as_any(&self) -> &(dyn Any + Send + 'static) {
        self
    }
}

#[derive(Debug)]
pub struct UnresolvedModule {
    pub file: HirFileId,
    pub decl: AstPtr<ast::Module>,
    pub candidate: RelativePathBuf,
}

impl Diagnostic for UnresolvedModule {
    fn message(&self) -> String {
        "unresolved module".to_string()
    }
    fn source(&self) -> Source<SyntaxNodePtr> {
        Source { file_id: self.file, ast: self.decl.into() }
    }
    fn as_any(&self) -> &(dyn Any + Send + 'static) {
        self
    }
}

#[derive(Debug)]
pub struct MissingFields {
    pub file: HirFileId,
    pub field_list: AstPtr<ast::RecordFieldList>,
    pub missed_fields: Vec<Name>,
}

impl Diagnostic for MissingFields {
    fn message(&self) -> String {
        "fill structure fields".to_string()
    }
    fn source(&self) -> Source<SyntaxNodePtr> {
        Source { file_id: self.file, ast: self.field_list.into() }
    }
    fn as_any(&self) -> &(dyn Any + Send + 'static) {
        self
    }
}

impl AstDiagnostic for MissingFields {
    type AST = ast::RecordFieldList;

    fn ast(&self, db: &impl AstDatabase) -> Self::AST {
        let root = db.parse_or_expand(self.source().file_id).unwrap();
        let node = self.source().ast.to_node(&root);
        ast::RecordFieldList::cast(node).unwrap()
    }
}

#[derive(Debug)]
pub struct MissingOkInTailExpr {
    pub file: HirFileId,
    pub expr: AstPtr<ast::Expr>,
}

impl Diagnostic for MissingOkInTailExpr {
    fn message(&self) -> String {
        "wrap return expression in Ok".to_string()
    }
    fn source(&self) -> Source<SyntaxNodePtr> {
        Source { file_id: self.file, ast: self.expr.into() }
    }
    fn as_any(&self) -> &(dyn Any + Send + 'static) {
        self
    }
}

impl AstDiagnostic for MissingOkInTailExpr {
    type AST = ast::Expr;

    fn ast(&self, db: &impl AstDatabase) -> Self::AST {
        let root = db.parse_or_expand(self.file).unwrap();
        let node = self.source().ast.to_node(&root);
        ast::Expr::cast(node).unwrap()
    }
}