use crate::core::compiler::{BuildConfig, MessageFormat};
use crate::core::Workspace;
use crate::ops::{CompileFilter, CompileOptions, NewOptions, Packages, VersionControl};
use crate::sources::CRATES_IO_REGISTRY;
use crate::util::important_paths::find_root_manifest_for_wd;
use crate::util::{paths, validate_package_name};
use crate::util::{
    print_available_benches, print_available_binaries, print_available_examples,
    print_available_tests,
};
use crate::CargoResult;
use clap::{self, SubCommand};
use failure::bail;
use std::ffi::{OsStr, OsString};
use std::fs;
use std::path::PathBuf;

pub use crate::core::compiler::CompileMode;
pub use crate::{CliError, CliResult, Config};
pub use clap::{AppSettings, Arg, ArgMatches};

pub type App = clap::App<'static, 'static>;

pub trait AppExt: Sized {
    fn _arg(self, arg: Arg<'static, 'static>) -> Self;

    fn arg_package_spec(
        self,
        package: &'static str,
        all: &'static str,
        exclude: &'static str,
    ) -> Self {
        self.arg_package_spec_simple(package)
            ._arg(opt("all", all))
            ._arg(multi_opt("exclude", "SPEC", exclude))
    }

    fn arg_package_spec_simple(self, package: &'static str) -> Self {
        self._arg(multi_opt("package", "SPEC", package).short("p"))
    }

    fn arg_package(self, package: &'static str) -> Self {
        self._arg(opt("package", package).short("p").value_name("SPEC"))
    }

    fn arg_jobs(self) -> Self {
        self._arg(
            opt("jobs", "Number of parallel jobs, defaults to # of CPUs")
                .short("j")
                .value_name("N"),
        )
    }

    fn arg_targets_all(
        self,
        lib: &'static str,
        bin: &'static str,
        bins: &'static str,
        example: &'static str,
        examples: &'static str,
        test: &'static str,
        tests: &'static str,
        bench: &'static str,
        benches: &'static str,
        all: &'static str,
    ) -> Self {
        self.arg_targets_lib_bin(lib, bin, bins)
            ._arg(optional_multi_opt("example", "NAME", example))
            ._arg(opt("examples", examples))
            ._arg(optional_multi_opt("test", "NAME", test))
            ._arg(opt("tests", tests))
            ._arg(optional_multi_opt("bench", "NAME", bench))
            ._arg(opt("benches", benches))
            ._arg(opt("all-targets", all))
    }

    fn arg_targets_lib_bin(self, lib: &'static str, bin: &'static str, bins: &'static str) -> Self {
        self._arg(opt("lib", lib))
            ._arg(optional_multi_opt("bin", "NAME", bin))
            ._arg(opt("bins", bins))
    }

    fn arg_targets_bins_examples(
        self,
        bin: &'static str,
        bins: &'static str,
        example: &'static str,
        examples: &'static str,
    ) -> Self {
        self._arg(optional_multi_opt("bin", "NAME", bin))
            ._arg(opt("bins", bins))
            ._arg(optional_multi_opt("example", "NAME", example))
            ._arg(opt("examples", examples))
    }

    fn arg_targets_bin_example(self, bin: &'static str, example: &'static str) -> Self {
        self._arg(optional_multi_opt("bin", "NAME", bin))
            ._arg(optional_multi_opt("example", "NAME", example))
    }

    fn arg_features(self) -> Self {
        self._arg(
            opt("features", "Space-separated list of features to activate")
                .multiple(true)
                .value_name("FEATURES"),
        )
        ._arg(opt("all-features", "Activate all available features"))
        ._arg(opt(
            "no-default-features",
            "Do not activate the `default` feature",
        ))
    }

    fn arg_release(self, release: &'static str) -> Self {
        self._arg(opt("release", release))
    }

    fn arg_doc(self, doc: &'static str) -> Self {
        self._arg(opt("doc", doc))
    }

    fn arg_target_triple(self, target: &'static str) -> Self {
        self._arg(opt("target", target).value_name("TRIPLE"))
    }

    fn arg_target_dir(self) -> Self {
        self._arg(
            opt("target-dir", "Directory for all generated artifacts").value_name("DIRECTORY"),
        )
    }

    fn arg_manifest_path(self) -> Self {
        self._arg(opt("manifest-path", "Path to Cargo.toml").value_name("PATH"))
    }

    fn arg_message_format(self) -> Self {
        self._arg(multi_opt("message-format", "FMT", "Error format"))
    }

    fn arg_build_plan(self) -> Self {
        self._arg(opt(
            "build-plan",
            "Output the build plan in JSON (unstable)",
        ))
    }

    fn arg_new_opts(self) -> Self {
        self._arg(
            opt(
                "vcs",
                "Initialize a new repository for the given version \
                 control system (git, hg, pijul, or fossil) or do not \
                 initialize any version control at all (none), overriding \
                 a global configuration.",
            )
            .value_name("VCS")
            .possible_values(&["git", "hg", "pijul", "fossil", "none"]),
        )
        ._arg(opt("bin", "Use a binary (application) template [default]"))
        ._arg(opt("lib", "Use a library template"))
        ._arg(
            opt("edition", "Edition to set for the crate generated")
                .possible_values(&["2015", "2018"])
                .value_name("YEAR"),
        )
        ._arg(
            opt(
                "name",
                "Set the resulting package name, defaults to the directory name",
            )
            .value_name("NAME"),
        )
    }

    fn arg_index(self) -> Self {
        self._arg(opt("index", "Registry index URL to upload the package to").value_name("INDEX"))
            ._arg(
                opt("host", "DEPRECATED, renamed to '--index'")
                    .value_name("HOST")
                    .hidden(true),
            )
    }

    fn arg_dry_run(self, dry_run: &'static str) -> Self {
        self._arg(opt("dry-run", dry_run))
    }
}

impl AppExt for App {
    fn _arg(self, arg: Arg<'static, 'static>) -> Self {
        self.arg(arg)
    }
}

pub fn opt(name: &'static str, help: &'static str) -> Arg<'static, 'static> {
    Arg::with_name(name).long(name).help(help)
}

pub fn optional_multi_opt(
    name: &'static str,
    value_name: &'static str,
    help: &'static str,
) -> Arg<'static, 'static> {
    opt(name, help)
        .value_name(value_name)
        .multiple(true)
        .min_values(0)
        .number_of_values(1)
}

pub fn multi_opt(
    name: &'static str,
    value_name: &'static str,
    help: &'static str,
) -> Arg<'static, 'static> {
    // Note that all `.multiple(true)` arguments in Cargo should specify
    // `.number_of_values(1)` as well, so that `--foo val1 val2` is
    // *not* parsed as `foo` with values ["val1", "val2"].
    // `number_of_values` should become the default in clap 3.
    opt(name, help)
        .value_name(value_name)
        .multiple(true)
        .number_of_values(1)
}

pub fn subcommand(name: &'static str) -> App {
    SubCommand::with_name(name).settings(&[
        AppSettings::UnifiedHelpMessage,
        AppSettings::DeriveDisplayOrder,
        AppSettings::DontCollapseArgsInUsage,
    ])
}

pub trait ArgMatchesExt {
    fn value_of_u32(&self, name: &str) -> CargoResult<Option<u32>> {
        let arg = match self._value_of(name) {
            None => None,
            Some(arg) => Some(arg.parse::<u32>().map_err(|_| {
                clap::Error::value_validation_auto(format!("could not parse `{}` as a number", arg))
            })?),
        };
        Ok(arg)
    }

    /// Returns value of the `name` command-line argument as an absolute path
    fn value_of_path(&self, name: &str, config: &Config) -> Option<PathBuf> {
        self._value_of(name).map(|path| config.cwd().join(path))
    }

    fn root_manifest(&self, config: &Config) -> CargoResult<PathBuf> {
        if let Some(path) = self.value_of_path("manifest-path", config) {
            // In general, we try to avoid normalizing paths in Cargo,
            // but in this particular case we need it to fix #3586.
            let path = paths::normalize_path(&path);
            if !path.ends_with("Cargo.toml") {
                failure::bail!("the manifest-path must be a path to a Cargo.toml file")
            }
            if fs::metadata(&path).is_err() {
                failure::bail!(
                    "manifest path `{}` does not exist",
                    self._value_of("manifest-path").unwrap()
                )
            }
            return Ok(path);
        }
        find_root_manifest_for_wd(config.cwd())
    }

    fn workspace<'a>(&self, config: &'a Config) -> CargoResult<Workspace<'a>> {
        let root = self.root_manifest(config)?;
        let mut ws = Workspace::new(&root, config)?;
        if config.cli_unstable().avoid_dev_deps {
            ws.set_require_optional_deps(false);
        }
        Ok(ws)
    }

    fn jobs(&self) -> CargoResult<Option<u32>> {
        self.value_of_u32("jobs")
    }

    fn target(&self) -> Option<String> {
        self._value_of("target").map(|s| s.to_string())
    }

    fn compile_options<'a>(
        &self,
        config: &'a Config,
        mode: CompileMode,
        workspace: Option<&Workspace<'a>>,
    ) -> CargoResult<CompileOptions<'a>> {
        let spec = Packages::from_flags(
            self._is_present("all"),
            self._values_of("exclude"),
            self._values_of("package"),
        )?;

        let mut message_format = None;
        let default_json = MessageFormat::Json {
            short: false,
            ansi: false,
            render_diagnostics: false,
        };
        for fmt in self._values_of("message-format") {
            for fmt in fmt.split(',') {
                let fmt = fmt.to_ascii_lowercase();
                match fmt.as_str() {
                    "json" => {
                        if message_format.is_some() {
                            bail!("cannot specify two kinds of `message-format` arguments");
                        }
                        message_format = Some(default_json);
                    }
                    "human" => {
                        if message_format.is_some() {
                            bail!("cannot specify two kinds of `message-format` arguments");
                        }
                        message_format = Some(MessageFormat::Human);
                    }
                    "short" => {
                        if message_format.is_some() {
                            bail!("cannot specify two kinds of `message-format` arguments");
                        }
                        message_format = Some(MessageFormat::Short);
                    }
                    "json-render-diagnostics" => {
                        if message_format.is_none() {
                            message_format = Some(default_json);
                        }
                        match &mut message_format {
                            Some(MessageFormat::Json {
                                render_diagnostics, ..
                            }) => *render_diagnostics = true,
                            _ => bail!("cannot specify two kinds of `message-format` arguments"),
                        }
                    }
                    "json-diagnostic-short" => {
                        if message_format.is_none() {
                            message_format = Some(default_json);
                        }
                        match &mut message_format {
                            Some(MessageFormat::Json { short, .. }) => *short = true,
                            _ => bail!("cannot specify two kinds of `message-format` arguments"),
                        }
                    }
                    "json-diagnostic-rendered-ansi" => {
                        if message_format.is_none() {
                            message_format = Some(default_json);
                        }
                        match &mut message_format {
                            Some(MessageFormat::Json { ansi, .. }) => *ansi = true,
                            _ => bail!("cannot specify two kinds of `message-format` arguments"),
                        }
                    }
                    s => bail!("invalid message format specifier: `{}`", s),
                }
            }
        }

        let mut build_config = BuildConfig::new(config, self.jobs()?, &self.target(), mode)?;
        build_config.message_format = message_format.unwrap_or(MessageFormat::Human);
        build_config.release = self._is_present("release");
        build_config.build_plan = self._is_present("build-plan");
        if build_config.build_plan {
            config
                .cli_unstable()
                .fail_if_stable_opt("--build-plan", 5579)?;
        };

        let opts = CompileOptions {
            config,
            build_config,
            features: self._values_of("features"),
            all_features: self._is_present("all-features"),
            no_default_features: self._is_present("no-default-features"),
            spec,
            filter: CompileFilter::from_raw_arguments(
                self._is_present("lib"),
                self._values_of("bin"),
                self._is_present("bins"),
                self._values_of("test"),
                self._is_present("tests"),
                self._values_of("example"),
                self._is_present("examples"),
                self._values_of("bench"),
                self._is_present("benches"),
                self._is_present("all-targets"),
            ),
            target_rustdoc_args: None,
            target_rustc_args: None,
            local_rustdoc_args: None,
            export_dir: None,
        };

        if let Some(ws) = workspace {
            self.check_optional_opts(ws, &opts)?;
        }

        Ok(opts)
    }

    fn compile_options_for_single_package<'a>(
        &self,
        config: &'a Config,
        mode: CompileMode,
        workspace: Option<&Workspace<'a>>,
    ) -> CargoResult<CompileOptions<'a>> {
        let mut compile_opts = self.compile_options(config, mode, workspace)?;
        compile_opts.spec = Packages::Packages(self._values_of("package"));
        Ok(compile_opts)
    }

    fn new_options(&self, config: &Config) -> CargoResult<NewOptions> {
        let vcs = self._value_of("vcs").map(|vcs| match vcs {
            "git" => VersionControl::Git,
            "hg" => VersionControl::Hg,
            "pijul" => VersionControl::Pijul,
            "fossil" => VersionControl::Fossil,
            "none" => VersionControl::NoVcs,
            vcs => panic!("Impossible vcs: {:?}", vcs),
        });
        NewOptions::new(
            vcs,
            self._is_present("bin"),
            self._is_present("lib"),
            self.value_of_path("path", config).unwrap(),
            self._value_of("name").map(|s| s.to_string()),
            self._value_of("edition").map(|s| s.to_string()),
            self.registry(config)?,
        )
    }

    fn registry(&self, config: &Config) -> CargoResult<Option<String>> {
        match self._value_of("registry") {
            Some(registry) => {
                validate_package_name(registry, "registry name", "")?;

                if registry == CRATES_IO_REGISTRY {
                    // If "crates.io" is specified, then we just need to return `None`,
                    // as that will cause cargo to use crates.io. This is required
                    // for the case where a default alternative registry is used
                    // but the user wants to switch back to crates.io for a single
                    // command.
                    Ok(None)
                } else {
                    Ok(Some(registry.to_string()))
                }
            }
            None => config.default_registry(),
        }
    }

    fn index(&self, config: &Config) -> CargoResult<Option<String>> {
        // TODO: deprecated. Remove once it has been decided `--host` can be removed
        // We may instead want to repurpose the host flag, as mentioned in issue
        // rust-lang/cargo#4208.
        let msg = "The flag '--host' is no longer valid.

Previous versions of Cargo accepted this flag, but it is being
deprecated. The flag is being renamed to 'index', as the flag
wants the location of the index. Please use '--index' instead.

This will soon become a hard error, so it's either recommended
to update to a fixed version or contact the upstream maintainer
about this warning.";

        let index = match self._value_of("host") {
            Some(host) => {
                config.shell().warn(&msg)?;
                Some(host.to_string())
            }
            None => self._value_of("index").map(|s| s.to_string()),
        };
        Ok(index)
    }

    fn check_optional_opts(
        &self,
        workspace: &Workspace<'_>,
        compile_opts: &CompileOptions<'_>,
    ) -> CargoResult<()> {
        if self.is_present_with_zero_values("example") {
            print_available_examples(workspace, compile_opts)?;
        }

        if self.is_present_with_zero_values("bin") {
            print_available_binaries(workspace, compile_opts)?;
        }

        if self.is_present_with_zero_values("bench") {
            print_available_benches(workspace, compile_opts)?;
        }

        if self.is_present_with_zero_values("test") {
            print_available_tests(workspace, compile_opts)?;
        }

        Ok(())
    }

    fn is_present_with_zero_values(&self, name: &str) -> bool {
        self._is_present(name) && self._value_of(name).is_none()
    }

    fn _value_of(&self, name: &str) -> Option<&str>;

    fn _values_of(&self, name: &str) -> Vec<String>;

    fn _value_of_os(&self, name: &str) -> Option<&OsStr>;

    fn _values_of_os(&self, name: &str) -> Vec<OsString>;

    fn _is_present(&self, name: &str) -> bool;
}

impl<'a> ArgMatchesExt for ArgMatches<'a> {
    fn _value_of(&self, name: &str) -> Option<&str> {
        self.value_of(name)
    }

    fn _value_of_os(&self, name: &str) -> Option<&OsStr> {
        self.value_of_os(name)
    }

    fn _values_of(&self, name: &str) -> Vec<String> {
        self.values_of(name)
            .unwrap_or_default()
            .map(|s| s.to_string())
            .collect()
    }

    fn _values_of_os(&self, name: &str) -> Vec<OsString> {
        self.values_of_os(name)
            .unwrap_or_default()
            .map(|s| s.to_os_string())
            .collect()
    }

    fn _is_present(&self, name: &str) -> bool {
        self.is_present(name)
    }
}

pub fn values(args: &ArgMatches<'_>, name: &str) -> Vec<String> {
    args._values_of(name)
}

pub fn values_os(args: &ArgMatches<'_>, name: &str) -> Vec<OsString> {
    args._values_of_os(name)
}

#[derive(PartialEq, PartialOrd, Eq, Ord)]
pub enum CommandInfo {
    BuiltIn { name: String, about: Option<String> },
    External { name: String, path: PathBuf },
}

impl CommandInfo {
    pub fn name(&self) -> &str {
        match self {
            CommandInfo::BuiltIn { name, .. } => name,
            CommandInfo::External { name, .. } => name,
        }
    }
}
