use crate::exitcode;

use crate::ui::UiError;

use hg::operations::{FindRootError, FindRootErrorKind};

use hg::utils::files::get_bytes_from_path;

use std::convert::From;

use std::path::PathBuf;

/// The kind of command error

#[derive(Debug)]

pub enum CommandErrorKind {

    /// The root of the repository cannot be found

    RootNotFound(PathBuf),

    /// The current directory cannot be found

    CurrentDirNotFound(std::io::Error),

    /// The standard output stream cannot be written to

    StdoutError,

    /// The standard error stream cannot be written to

    StderrError,

    /// The command aborted

    Abort(Option<Vec<u8>>),

    /// A mercurial capability as not been implemented.

    Unimplemented,

}

impl CommandErrorKind {

    pub fn get_exit_code(&self) -> exitcode::ExitCode {

        match self {

            CommandErrorKind::RootNotFound(_) => exitcode::ABORT,

            CommandErrorKind::CurrentDirNotFound(_) => exitcode::ABORT,

            CommandErrorKind::StdoutError => exitcode::ABORT,

            CommandErrorKind::StderrError => exitcode::ABORT,

            CommandErrorKind::Abort(_) => exitcode::ABORT,

            CommandErrorKind::Unimplemented => exitcode::UNIMPLEMENTED_COMMAND,

        }

    }

    /// Return the message corresponding to the error kind if any

    pub fn get_error_message_bytes(&self) -> Option<Vec<u8>> {

        match self {

            // TODO use formating macro

            CommandErrorKind::RootNotFound(path) => {

                let bytes = get_bytes_from_path(path);

                Some(

                    [

                        b"abort: no repository found in '",

                        bytes.as_slice(),

                        b"' (.hg not found)!\n",

                    ]

                    .concat(),

                )

            }

            // TODO use formating macro

            CommandErrorKind::CurrentDirNotFound(e) => Some(

                [

                    b"abort: error getting current working directory: ",

                    e.to_string().as_bytes(),

                    b"\n",

                ]

                .concat(),

            ),

            CommandErrorKind::Abort(message) => message.to_owned(),

            _ => None,

        }

    }

}

/// The error type for the Command trait

#[derive(Debug)]

pub struct CommandError {

    pub kind: CommandErrorKind,

}

impl CommandError {

    /// Exist the process with the corresponding exit code.

    pub fn exit(&self) {

        std::process::exit(self.kind.get_exit_code())

    }

    /// Return the message corresponding to the command error if any

    pub fn get_error_message_bytes(&self) -> Option<Vec<u8>> {

        self.kind.get_error_message_bytes()

    }

}

impl From<CommandErrorKind> for CommandError {

    fn from(kind: CommandErrorKind) -> Self {

        CommandError { kind }

    }

}

impl From<UiError> for CommandError {

    fn from(error: UiError) -> Self {

        CommandError {

            kind: match error {

                UiError::StdoutError(_) => CommandErrorKind::StdoutError,

                UiError::StderrError(_) => CommandErrorKind::StderrError,

            },

        }

    }

}

impl From<FindRootError> for CommandError {

    fn from(err: FindRootError) -> Self {

        match err.kind {

            FindRootErrorKind::RootNotFound(path) => CommandError {

                kind: CommandErrorKind::RootNotFound(path),

            },

            FindRootErrorKind::GetCurrentDirError(e) => CommandError {

                kind: CommandErrorKind::CurrentDirNotFound(e),

            },

        }

    }

}