// Copyright (c) 2018 FaultyRAM
//
// Licensed under the Apache License, Version 2.0
// <LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0> or the
// MIT license <LICENSE-MIT or http://opensource.org/licenses/MIT>, at
// your option. This file may not be copied, modified, or distributed
// except according to those terms.

//! Provides support for invoking and capturing the output of the vswhere utility.

#![cfg(target_os = "windows")]
#![forbid(warnings)]
#![forbid(future_incompatible)]
#![deny(unused)]
#![forbid(box_pointers)]
#![forbid(missing_copy_implementations)]
#![forbid(missing_debug_implementations)]
#![forbid(missing_docs)]
#![forbid(trivial_casts)]
#![forbid(trivial_numeric_casts)]
#![forbid(unused_import_braces)]
#![deny(unused_qualifications)]
#![forbid(unused_results)]
#![forbid(variant_size_differences)]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy))]
#![cfg_attr(feature = "cargo-clippy", deny(clippy_pedantic))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_cargo))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_complexity))]
#![cfg_attr(feature = "cargo-clippy", deny(clippy_correctness))]
#![cfg_attr(feature = "cargo-clippy", deny(clippy_perf))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_style))]

extern crate chrono;
extern crate semver;
extern crate serde;
#[macro_use]
extern crate serde_derive;
extern crate serde_json;
extern crate url;
extern crate url_serde;
extern crate winapi;

use chrono::offset::Utc;
use chrono::DateTime;
use semver::Version;
use serde::de::{Unexpected, Visitor};
use serde::{Deserialize, Deserializer, Serialize, Serializer};
use std::ffi::OsString;
use std::fmt::{self, Display, Formatter};
use std::io::{self, ErrorKind};
use std::iter;
use std::ops::Range;
use std::os::windows::ffi::OsStringExt;
use std::path::{Path, PathBuf};
use std::process::Command;
use std::ptr;
use std::slice;
use std::str;
use url::Url;

#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
/// A version number that consists of four integers, widely used within the Windows world.
pub struct FourPointVersion {
    major: u16,
    minor: u16,
    revision: u16,
    build: u16,
}

#[derive(Clone, Debug)]
/// Builder-style configuration for a vswhere instance.
pub struct Config {
    prerelease: bool,
    products: Vec<String>,
    requires: Vec<String>,
    requires_any: bool,
    version: Option<Range<FourPointVersion>>,
    latest: bool,
}

#[cfg_attr(feature = "cargo-clippy", allow(similar_names))]
#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
#[serde(rename_all = "camelCase")]
/// Information about a Visual Studio installation.
pub struct InstallInfo {
    instance_id: String,
    install_date: DateTime<Utc>,
    installation_name: String,
    installation_path: PathBuf,
    installation_version: FourPointVersion,
    product_id: String,
    product_path: PathBuf,
    is_prerelease: bool,
    display_name: String,
    description: String,
    channel_id: String,
    channel_path: PathBuf,
    #[serde(with = "url_serde")]
    channel_uri: Url,
    engine_path: PathBuf,
    #[serde(with = "url_serde")]
    release_notes: Url,
    #[serde(with = "url_serde")]
    third_party_notices: Url,
    update_date: DateTime<Utc>,
    catalog: InstallCatalog,
    properties: InstallProperties,
}

#[cfg_attr(feature = "cargo-clippy", allow(similar_names))]
#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
#[serde(rename_all = "camelCase")]
/// Catalog information for a Visual Studio installation.
pub struct InstallCatalog {
    build_branch: String,
    build_version: FourPointVersion,
    id: String,
    local_build: String,
    manifest_name: String,
    manifest_type: String,
    product_display_version: String,
    product_line: String,
    product_line_version: String,
    product_milestone: String,
    #[serde(deserialize_with = "deserialize_uppercase_bool")]
    #[serde(serialize_with = "serialize_uppercase_bool")]
    product_milestone_is_pre_release: bool,
    product_name: String,
    product_patch_version: String,
    product_pre_release_milestone_suffix: String,
    product_release: String,
    product_semantic_version: Version,
    required_engine_version: FourPointVersion,
}

#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
#[serde(rename_all = "camelCase")]
/// Property information for a Visual Studio installation.
pub struct InstallProperties {
    campaign_id: String,
    channel_manifest_id: String,
    nickname: String,
    setup_engine_file_path: PathBuf,
}

fn deserialize_uppercase_bool<'de, D: Deserializer<'de>>(
    deserializer: D,
) -> Result<bool, D::Error> {
    struct UppercaseBoolVisitor;

    impl<'de> Visitor<'de> for UppercaseBoolVisitor {
        type Value = bool;

        fn expecting(&self, formatter: &mut Formatter) -> fmt::Result {
            write!(formatter, r#"a string, either `"True"` or `"False"`"#)
        }

        fn visit_str<E: serde::de::Error>(self, v: &str) -> Result<Self::Value, E> {
            let lower = v.to_lowercase();
            let lower_trim = lower.trim();
            if lower_trim == "true" {
                Ok(true)
            } else if lower_trim == "false" {
                Ok(false)
            } else {
                Err(E::invalid_value(Unexpected::Str(v), &self))
            }
        }
    }

    deserializer.deserialize_str(UppercaseBoolVisitor)
}

#[cfg_attr(feature = "cargo-clippy", allow(trivially_copy_pass_by_ref))]
fn serialize_uppercase_bool<S: Serializer>(
    boolean: &bool,
    serializer: S,
) -> Result<S::Ok, S::Error> {
    if *boolean {
        serializer.serialize_str("True")
    } else {
        serializer.serialize_str("False")
    }
}

impl FourPointVersion {
    /// Creates a new version number using the given values.
    pub fn new(major: u16, minor: u16, revision: u16, build: u16) -> Self {
        Self {
            major,
            minor,
            revision,
            build,
        }
    }

    /// Returns the major version number.
    pub fn major(self) -> u16 {
        self.major
    }

    /// Returns the major version number.
    pub fn minor(self) -> u16 {
        self.minor
    }

    /// Returns the major version number.
    pub fn revision(self) -> u16 {
        self.revision
    }

    /// Returns the major version number.
    pub fn build(self) -> u16 {
        self.build
    }
}

impl<'de> Deserialize<'de> for FourPointVersion {
    fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
        struct FourPointVersionVisitor;

        impl<'de> Visitor<'de> for FourPointVersionVisitor {
            type Value = FourPointVersion;

            fn expecting(&self, formatter: &mut Formatter) -> fmt::Result {
                write!(
                    formatter,
                    "one to four 16-bit unsigned integers separated by a period (`.`)"
                )
            }

            fn visit_str<E: serde::de::Error>(self, v: &str) -> Result<Self::Value, E> {
                fn parse_number<E: serde::de::Error>(
                    visitor: &FourPointVersionVisitor,
                    chunk: &str,
                ) -> Result<u16, E> {
                    u16::from_str_radix(chunk, 10)
                        .map_err(|_| E::invalid_value(Unexpected::Str(chunk), visitor))
                }
                let iter = v.split('.');
                let len = iter.clone().count();
                if len < 1 || len > 4 {
                    Err(E::invalid_length(len, &self))
                } else {
                    let mut version_getter = iter.chain(iter::repeat("0"));
                    Ok(FourPointVersion::new(
                        parse_number(&self, version_getter.next().unwrap())?,
                        parse_number(&self, version_getter.next().unwrap())?,
                        parse_number(&self, version_getter.next().unwrap())?,
                        parse_number(&self, version_getter.next().unwrap())?,
                    ))
                }
            }
        }

        deserializer.deserialize_str(FourPointVersionVisitor)
    }
}

impl Display for FourPointVersion {
    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
        write!(
            f,
            "{}.{}.{}.{}",
            self.major, self.minor, self.revision, self.build
        )
    }
}

impl Serialize for FourPointVersion {
    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
        serializer.collect_str(&self)
    }
}

impl Config {
    /// Creates a new `Config` instance with default values.
    pub fn new() -> Self {
        Self {
            prerelease: false,
            products: Vec::new(),
            requires: Vec::new(),
            requires_any: false,
            version: None,
            latest: false,
        }
    }

    /// Specifies whether to include pre-release versions of Visual Studio in search results.
    ///
    /// By default this is `false`.
    pub fn find_prerelease_versions(&mut self, prerelease: bool) -> &mut Self {
        self.prerelease = prerelease;
        self
    }

    /// Adds a string to the product ID (Visual Studio edition) whitelist.
    ///
    /// A list of valid product and component IDs is maintained
    /// [here](https://docs.microsoft.com/en-us/visualstudio/install/workload-and-component-ids).
    ///
    /// By default the product ID whitelist is empty, which is equivalent to passing `-products *`
    /// to vswhere (retrieves information about every installed product, as opposed to just
    /// Community, Professional and Enterprise). If the product ID whitelist is non-empty, versions
    /// of Visual Studio without a matching product ID are excluded from search results.
    pub fn whitelist_product_id<T: ToString + ?Sized>(&mut self, product_id: &T) -> &mut Self {
        self.products.push(product_id.to_string());
        self
    }

    /// Adds a string to the component ID whitelist.
    ///
    /// A list of valid product and component IDs is maintained
    /// [here](https://docs.microsoft.com/en-us/visualstudio/install/workload-and-component-ids).
    ///
    /// By default the component ID whitelist is empty, in which case it is not used. If the
    /// component ID whitelist is non-empty, versions of Visual Studio are excluded from search
    /// results based on the filtering method in use (see `Config::require_any_component` for
    /// more information).
    pub fn whitelist_component_id<T: ToString + ?Sized>(&mut self, component_id: &T) -> &mut Self {
        self.requires.push(component_id.to_string());
        self
    }

    /// Specifies the method to use for component ID filtering.
    ///
    /// If `true`, Visual Studio versions are excluded from search results if they do not provide
    /// at least one whitelisted component. Otherwise if `false` (the default value), Visual Studio
    /// versions are excluded if they do not provide every whitelisted component.
    ///
    /// This is only meaningful if the component ID whitelist is non-empty, as filtering by
    /// component ID is disabled otherwise.
    pub fn require_any_component(&mut self, require_any: bool) -> &mut Self {
        self.requires_any = require_any;
        self
    }

    /// Excludes Visual Studio installations whose version number falls outside of a given range.
    ///
    /// By default no installations are excluded based on version number.
    pub fn version_number_range(&mut self, range: Range<FourPointVersion>) -> &mut Self {
        self.version = Some(range);
        self
    }

    /// If `true`, include only the most current and most recently installed versions of Visual
    /// Studio in search results.
    ///
    /// By default this is `false`.
    pub fn only_latest_versions(&mut self, latest: bool) -> &mut Self {
        self.latest = latest;
        self
    }

    /// Invokes a vswhere instance installed in a default location, using the current
    /// configuration.
    ///
    /// This method tries running known vswhere instances, stopping at the first successful
    /// invocation, in the following order:
    ///
    /// 1. `[ProgramData]\chocolatey\bin\vswhere.exe`
    /// 2. `[ProgramFilesX86]\Microsoft Visual Studio\Installer\vswhere.exe`
    ///
    /// Note that `[ProgramData]` and `[ProgramFilesX86]` correspond to paths returned from the
    /// Windows API function `SHGetKnownFolderPath`.
    pub fn run_default_path(&self) -> io::Result<Vec<InstallInfo>> {
        use winapi::ctypes::c_void;
        use winapi::shared::ntdef::PWSTR;
        use winapi::shared::winerror::S_OK;
        use winapi::um::combaseapi::CoTaskMemFree;
        use winapi::um::knownfolders::{FOLDERID_ProgramData, FOLDERID_ProgramFilesX86};
        use winapi::um::shlobj::SHGetKnownFolderPath;
        use winapi::um::shtypes::REFKNOWNFOLDERID;

        fn get_known_folder_path(id: REFKNOWNFOLDERID) -> io::Result<PathBuf> {
            struct KnownFolderPath(PWSTR);

            impl Drop for KnownFolderPath {
                fn drop(&mut self) {
                    unsafe {
                        CoTaskMemFree(self.0 as *mut c_void);
                    }
                }
            }

            unsafe {
                let mut path = KnownFolderPath(ptr::null_mut());
                let hres = SHGetKnownFolderPath(id, 0, ptr::null_mut(), &mut path.0);
                if hres == S_OK {
                    let mut wide_string = path.0;
                    let mut len = 0;
                    while wide_string.read() != 0 {
                        wide_string = wide_string.offset(1);
                        len += 1;
                    }
                    let ws_slice = slice::from_raw_parts(path.0, len);
                    let os_string = OsString::from_wide(ws_slice);
                    Ok(Path::new(&os_string).to_owned())
                } else {
                    Err(io::Error::last_os_error())
                }
            }
        }

        let pd = get_known_folder_path(&FOLDERID_ProgramData)
            .map(|p| p.join(r"chocolatey\bin\vswhere.exe"))?;
        self.run_custom_path(pd).or_else(|e| {
            if e.kind() == ErrorKind::NotFound {
                get_known_folder_path(&FOLDERID_ProgramFilesX86)
                    .map(|p| p.join(r"Microsoft Visual Studio\Installer\vswhere.exe"))
                    .and_then(|p| self.run_custom_path(p))
            } else {
                Err(e)
            }
        })
    }

    /// Invokes a vswhere instance at the specified path, using the current configuration.
    ///
    /// The specified path must point to an executable, rather than a folder.
    pub fn run_custom_path<P: AsRef<Path>>(&self, path: P) -> io::Result<Vec<InstallInfo>> {
        let mut cmd = Command::new(path.as_ref());
        if self.prerelease {
            let _ = cmd.arg("-prerelease");
        }
        let _ = cmd.arg("-products");
        if self.products.is_empty() {
            let _ = cmd.arg("*");
        } else {
            let _ = cmd.args(&self.products);
        }
        if !self.requires.is_empty() {
            let _ = cmd.arg("-requires").args(&self.requires);
        }
        if self.requires_any {
            let _ = cmd.arg("-requiresAny");
        }
        if let Some(version_range) = self.version.as_ref() {
            let _ = cmd.args(&[
                "-version",
                &format!("[{},{})", version_range.start, version_range.end),
            ]);
        }
        if self.latest {
            let _ = cmd.arg("-latest");
        }
        cmd.args(&["-format", "json", "-utf8"])
            .output()
            .map(|output| {
                assert!(output.status.success());
                let json = str::from_utf8(&output.stdout).expect("vswhere returned invalid UTF-8");
                serde_json::from_str(json).expect("vswhere returned invalid JSON")
            })
    }
}

impl Default for Config {
    fn default() -> Self {
        Self::new()
    }
}

impl InstallInfo {
    /// Returns the string that uniquely identifies a Visual Studio instance.
    pub fn instance_id(&self) -> &str {
        &self.instance_id
    }

    /// Returns the date and time when a Visual Studio instance was installed.
    pub fn install_date(&self) -> &DateTime<Utc> {
        &self.install_date
    }

    /// Returns the internal name of a Visual Studio instance.
    pub fn installation_name(&self) -> &str {
        &self.installation_name
    }

    /// Returns the filesystem path to a Visual Studio instance.
    pub fn installation_path(&self) -> &Path {
        &self.installation_path
    }

    /// Returns the product version number for a Visual Studio instance.
    pub fn installation_version(&self) -> &FourPointVersion {
        &self.installation_version
    }

    /// Returns the product ID for a Visual Studio instance.
    pub fn product_id(&self) -> &str {
        &self.product_id
    }

    /// Returns the filesystem path to the main executable for a Visual Studio instance.
    pub fn product_path(&self) -> &Path {
        &self.product_path
    }

    /// Returns `true` if a Visual Studio instance is a prerelease version, or `false` otherwise.
    pub fn is_prerelease(&self) -> bool {
        self.is_prerelease
    }

    /// Returns the human-readable name of a Visual Studio instance.
    pub fn display_name(&self) -> &str {
        &self.display_name
    }

    /// Returns the human-readable description for a Visual Studio instance.
    pub fn description(&self) -> &str {
        &self.description
    }

    /// Returns the ID of the release channel that a Visual Studio instance is associated with.
    pub fn channel_id(&self) -> &str {
        &self.channel_id
    }

    /// Returns the filesystem path to the catalog file for the release channel that a Visual
    /// Studio instance is associated with.
    pub fn channel_path(&self) -> &Path {
        &self.channel_path
    }

    /// Returns the URL from where release channel updates are fetched.
    pub fn channel_url(&self) -> &Url {
        &self.channel_uri
    }

    /// {TODO}
    pub fn engine_path(&self) -> &Path {
        &self.engine_path
    }

    /// Returns the URL to the release notes for a Visual Studio instance.
    pub fn release_notes(&self) -> &Url {
        &self.release_notes
    }

    /// Returns the URL to the third-party notices for a Visual Studio instance.
    pub fn third_party_notices(&self) -> &Url {
        &self.third_party_notices
    }

    /// Returns the date and time when a Visual Studio instance was last updated.
    pub fn update_date(&self) -> &DateTime<Utc> {
        &self.update_date
    }

    /// Returns the catalog information for a Visual Studio instance.
    pub fn catalog(&self) -> &InstallCatalog {
        &self.catalog
    }

    /// Returns the property information for a Visual Studio instance.
    pub fn properties(&self) -> &InstallProperties {
        &self.properties
    }
}

impl InstallCatalog {
    /// {TODO}
    pub fn build_branch(&self) -> &str {
        &self.build_branch
    }

    /// {TODO}
    pub fn build_version(&self) -> &FourPointVersion {
        &self.build_version
    }

    /// {TODO}
    pub fn id(&self) -> &str {
        &self.id
    }

    /// {TODO}
    pub fn local_build(&self) -> &str {
        &self.local_build
    }

    /// {TODO}
    pub fn manifest_name(&self) -> &str {
        &self.manifest_name
    }

    /// {TODO}
    pub fn manifest_type(&self) -> &str {
        &self.manifest_type
    }

    /// Returns the human-readable version number for a Visual Studio instance.
    pub fn product_display_version(&self) -> &str {
        &self.product_display_version
    }

    /// {TODO}
    pub fn product_line(&self) -> &str {
        &self.product_line
    }

    /// {TODO}
    pub fn product_line_version(&self) -> &str {
        &self.product_line_version
    }

    /// {TODO}
    pub fn product_milestone(&self) -> &str {
        &self.product_milestone
    }

    /// {TODO}
    pub fn product_milestone_is_pre_release(&self) -> bool {
        unimplemented!()
    }

    /// {TODO}
    pub fn product_name(&self) -> &str {
        &self.product_name
    }

    /// {TODO}
    pub fn product_patch_version(&self) -> &str {
        &self.product_patch_version
    }

    /// {TODO}
    pub fn product_pre_release_milestone_suffix(&self) -> &str {
        &self.product_pre_release_milestone_suffix
    }

    /// {TODO}
    pub fn product_release(&self) -> &str {
        &self.product_release
    }

    /// Returns the semver-compliant version number for a Visual Studio instance.
    pub fn product_semantic_version(&self) -> &Version {
        &self.product_semantic_version
    }

    /// {TODO}
    pub fn required_engine_version(&self) -> &FourPointVersion {
        &self.required_engine_version
    }
}

impl InstallProperties {
    /// {TODO}
    pub fn campaign_id(&self) -> &str {
        &self.campaign_id
    }

    /// {TODO}
    pub fn channel_manifest_id(&self) -> &str {
        &self.channel_manifest_id
    }

    /// Returns the user-assigned nickname for a Visual Studio instance.
    pub fn nickname(&self) -> &str {
        &self.nickname
    }

    /// {TODO}
    pub fn setup_engine_file_path(&self) -> &Path {
        &self.setup_engine_file_path
    }
}

#[cfg(test)]
mod tests {
    use {Config, FourPointVersion};

    #[test]
    fn test_default() {
        let _ = Config::default().run_default_path().expect("failed");
    }

    #[test]
    fn test_args() {
        let _ = Config::new()
            .find_prerelease_versions(true)
            .whitelist_product_id("*")
            .whitelist_component_id("Microsoft.VisualStudio.Component.VC.Tools.x86.x64")
            .require_any_component(true)
            .version_number_range(
                FourPointVersion::new(
                    u16::min_value(),
                    u16::min_value(),
                    u16::min_value(),
                    u16::min_value(),
                )
                    ..FourPointVersion::new(
                        u16::max_value(),
                        u16::max_value(),
                        u16::max_value(),
                        u16::max_value(),
                    ),
            )
            .only_latest_versions(true)
            .run_default_path()
            .expect("failed");
    }

    #[test]
    fn test_fake_product() {
        let _ = Config::new()
            .whitelist_product_id("The quick brown fox jumps over the lazy dog.")
            .run_default_path()
            .expect("failed");
    }
}