use crate::ui::utf8_to_local;

use crate::ui::UiError;

use crate::NoRepoInCwdError;

use format_bytes::format_bytes;

use hg::config::{ConfigError, ConfigParseError, ConfigValueParseError};

use hg::dirstate_tree::on_disk::DirstateV2ParseError;

use hg::errors::HgError;

use hg::exit_codes;

use hg::repo::RepoError;

use hg::revlog::revlog::RevlogError;

use hg::sparse::SparseConfigError;

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

use hg::{DirstateError, DirstateMapError, StatusError};

use std::convert::From;

/// The kind of command error

#[derive(Debug)]

pub enum CommandError {

    /// Exit with an error message and "standard" failure exit code.

    Abort {

        message: Vec<u8>,

        detailed_exit_code: exit_codes::ExitCode,

        hint: Option<Vec<u8>>,

    },

    /// Exit with a failure exit code but no message.

    Unsuccessful,

    /// Encountered something (such as a CLI argument, repository layout, …)

    /// not supported by this version of `rhg`. Depending on configuration

    /// `rhg` may attempt to silently fall back to Python-based `hg`, which

    /// may or may not support this feature.

    UnsupportedFeature { message: Vec<u8> },

    /// The fallback executable does not exist (or has some other problem if

    /// we end up being more precise about broken fallbacks).

    InvalidFallback { path: Vec<u8>, err: String },

}

impl CommandError {

    pub fn abort(message: impl AsRef<str>) -> Self {

        CommandError::abort_with_exit_code(message, exit_codes::ABORT)

    }

    pub fn abort_with_exit_code(

        message: impl AsRef<str>,

        detailed_exit_code: exit_codes::ExitCode,

    ) -> Self {

        CommandError::Abort {

            // TODO: bytes-based (instead of Unicode-based) formatting

            // of error messages to handle non-UTF-8 filenames etc:

            // https://www.mercurial-scm.org/wiki/EncodingStrategy#Mixing_output

            message: utf8_to_local(message.as_ref()).into(),

            detailed_exit_code: detailed_exit_code,

            hint: None,

        }

    }

    pub fn abort_with_exit_code_and_hint(

        message: impl AsRef<str>,

        detailed_exit_code: exit_codes::ExitCode,

        hint: Option<impl AsRef<str>>,

    ) -> Self {

        CommandError::Abort {

            message: utf8_to_local(message.as_ref()).into(),

            detailed_exit_code,

            hint: hint.map(|h| utf8_to_local(h.as_ref()).into()),

        }

    }

    pub fn abort_with_exit_code_bytes(

        message: impl AsRef<[u8]>,

        detailed_exit_code: exit_codes::ExitCode,

    ) -> Self {

        // TODO: use this everywhere it makes sense instead of the string

        // version.

        CommandError::Abort {

            message: message.as_ref().into(),

            detailed_exit_code,

            hint: None,

        }

    }

    pub fn unsupported(message: impl AsRef<str>) -> Self {

        CommandError::UnsupportedFeature {

            message: utf8_to_local(message.as_ref()).into(),

        }

    }

}

/// For now we don’t differenciate between invalid CLI args and valid for `hg`

/// but not supported yet by `rhg`.

impl From<clap::Error> for CommandError {

    fn from(error: clap::Error) -> Self {

        CommandError::unsupported(error.to_string())

    }

}

impl From<HgError> for CommandError {

    fn from(error: HgError) -> Self {

        match error {

            HgError::UnsupportedFeature(message) => {

                CommandError::unsupported(message)

            }

            HgError::CensoredNodeError => {

                CommandError::unsupported("Encountered a censored node")

            }

            HgError::Abort {

                message,

                detailed_exit_code,

                hint,

            } => CommandError::abort_with_exit_code_and_hint(

                message,

                detailed_exit_code,

                hint,

            ),

            _ => CommandError::abort(error.to_string()),

        }

    }

}

impl From<ConfigValueParseError> for CommandError {

    fn from(error: ConfigValueParseError) -> Self {

        CommandError::abort_with_exit_code(

            error.to_string(),

            exit_codes::CONFIG_ERROR_ABORT,

        )

    }

}

impl From<UiError> for CommandError {

    fn from(_error: UiError) -> Self {

        // If we already failed writing to stdout or stderr,

        // writing an error message to stderr about it would be likely to fail

        // too.

        CommandError::abort("")

    }

}

impl From<RepoError> for CommandError {

    fn from(error: RepoError) -> Self {

        match error {

            RepoError::NotFound { at } => {

                CommandError::abort_with_exit_code_bytes(

                    format_bytes!(

                        b"abort: repository {} not found",

                        get_bytes_from_path(at)

                    ),

                    exit_codes::ABORT,

                )

            }

            RepoError::ConfigParseError(error) => error.into(),

            RepoError::Other(error) => error.into(),

        }

    }

}

impl<'a> From<&'a NoRepoInCwdError> for CommandError {

    fn from(error: &'a NoRepoInCwdError) -> Self {

        let NoRepoInCwdError { cwd } = error;

        CommandError::abort_with_exit_code_bytes(

            format_bytes!(

                b"abort: no repository found in '{}' (.hg not found)!",

                get_bytes_from_path(cwd)

            ),

            exit_codes::ABORT,

        )

    }

}

impl From<ConfigError> for CommandError {

    fn from(error: ConfigError) -> Self {

        match error {

            ConfigError::Parse(error) => error.into(),

            ConfigError::Other(error) => error.into(),

        }

    }

}

impl From<ConfigParseError> for CommandError {

    fn from(error: ConfigParseError) -> Self {

        let ConfigParseError {

            origin,

            line,

            message,

        } = error;

        let line_message = if let Some(line_number) = line {

            format_bytes!(b":{}", line_number.to_string().into_bytes())

        } else {

            Vec::new()

        };

        CommandError::abort_with_exit_code_bytes(

            format_bytes!(

                b"config error at {}{}: {}",

                origin,

                line_message,

                message

            ),

            exit_codes::CONFIG_ERROR_ABORT,

        )

    }

}

impl From<(RevlogError, &str)> for CommandError {

    fn from((err, rev): (RevlogError, &str)) -> CommandError {

        match err {

            RevlogError::WDirUnsupported => CommandError::abort(

                "abort: working directory revision cannot be specified",

            ),

            RevlogError::InvalidRevision => CommandError::abort(format!(

                "abort: invalid revision identifier: {}",

                rev

            )),

            RevlogError::AmbiguousPrefix => CommandError::abort(format!(

                "abort: ambiguous revision identifier: {}",

                rev

            )),

            RevlogError::Other(error) => error.into(),

        }

    }

}

impl From<StatusError> for CommandError {

    fn from(error: StatusError) -> Self {

        CommandError::abort(format!("{}", error))

    }

}

impl From<DirstateMapError> for CommandError {

    fn from(error: DirstateMapError) -> Self {

        CommandError::abort(format!("{}", error))

    }

}

impl From<DirstateError> for CommandError {

    fn from(error: DirstateError) -> Self {

        match error {

            DirstateError::Common(error) => error.into(),

            DirstateError::Map(error) => error.into(),

        }

    }

}

impl From<DirstateV2ParseError> for CommandError {

    fn from(error: DirstateV2ParseError) -> Self {

        HgError::from(error).into()

    }

}

impl From<SparseConfigError> for CommandError {

    fn from(e: SparseConfigError) -> Self {

        match e {

            SparseConfigError::IncludesAfterExcludes { context } => {

                Self::abort_with_exit_code_bytes(

                    format_bytes!(

                        b"{} config cannot have includes after excludes",

                        context

                    ),

                    exit_codes::CONFIG_PARSE_ERROR_ABORT,

                )

            }

            SparseConfigError::EntryOutsideSection { context, line } => {

                Self::abort_with_exit_code_bytes(

                    format_bytes!(

                        b"{} config entry outside of section: {}",

                        context,

                        &line,

                    ),

                    exit_codes::CONFIG_PARSE_ERROR_ABORT,

                )

            }

            SparseConfigError::HgError(e) => Self::from(e),

            SparseConfigError::PatternError(e) => {

                Self::unsupported(format!("{}", e))

            }

        }

    }

}