// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// 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.

// rustpkg - a package manager and build system for Rust

#[link(name = "rustpkg",
       vers = "0.7-pre",
       uuid = "25de5e6e-279e-4a20-845c-4cabae92daaf",
       url = "https://github.com/mozilla/rust/tree/master/src/librustpkg")];

#[license = "MIT/ASL2"];
#[crate_type = "lib"];
#[no_core];
#[allow(vecs_implicitly_copyable,
        non_implicitly_copyable_typarams)];

extern mod core(vers = "0.7-pre");
extern mod std(vers = "0.7-pre");
extern mod rustc(vers = "0.7-pre");
extern mod syntax(vers = "0.7-pre");

use core::*;
pub use core::path::Path;
use core::container::Map;
use core::hashmap::HashMap;
use core::io::WriterUtil;
use rustc::driver::{driver, session};
use rustc::metadata::filesearch;
use std::net::url;
use std::{getopts};
use syntax::{ast, diagnostic};
use util::*;
use path_util::{dest_dir, normalize};
use rustc::driver::session::{lib_crate, bin_crate, unknown_crate, crate_type};

mod conditions;
mod usage;
mod path_util;
mod util;

/// A PkgScript represents user-supplied custom logic for
/// special build hooks. This only exists for packages with
/// an explicit package script.
struct PkgScript {
    /// Uniquely identifies this package
    id: PkgId,
    // Used to have this field:    deps: ~[(~str, Option<~str>)]
    // but I think it shouldn't be stored here
    /// The contents of the package script: either a file path,
    /// or a string containing the text of the input
    input: driver::input,
    /// The session to use *only* for compiling the custom
    /// build script
    sess: session::Session,
    /// The config for compiling the custom build script
    cfg: ast::crate_cfg,
    /// The crate for the custom build script
    crate: @ast::crate,
    /// Directory in which to store build output
    build_dir: Path
}

impl PkgScript {
    /// Given the path name for a package script
    /// and a package ID, parse the package script into
    /// a PkgScript that we can then execute
    fn parse(script: Path, id: PkgId) -> PkgScript {
        // Get the executable name that was invoked
        let binary = os::args()[0];
        // Build the rustc session data structures to pass
        // to the compiler
        let options = @session::options {
            binary: binary,
            crate_type: session::bin_crate,
            .. *session::basic_options()
        };
        let input = driver::file_input(script);
        let sess = driver::build_session(options, diagnostic::emit);
        let cfg = driver::build_configuration(sess, binary, input);
        let (crate, _) = driver::compile_upto(sess, cfg, input,
                                              driver::cu_parse, None);
        let work_dir = dest_dir(id);

        debug!("Returning package script with id %?", id);

        PkgScript {
            id: id,
            input: input,
            sess: sess,
            cfg: cfg,
            crate: crate,
            build_dir: work_dir
        }
    }

    /// Run the contents of this package script, where <what>
    /// is the command to pass to it (e.g., "build", "clean", "install")
    /// Returns a pair of an exit code and list of configs (obtained by
    /// calling the package script's configs() function if it exists
    // FIXME (#4432): Use workcache to only compile the script when changed
    fn run_custom(&self, what: ~str) -> (~[~str], ExitCode) {
        debug!("run_custom: %s", what);
        let sess = self.sess;

        debug!("Working directory = %s", self.build_dir.to_str());
        // Collect together any user-defined commands in the package script
        let crate = util::ready_crate(sess, self.crate);
        debug!("Building output filenames with script name %s",
               driver::source_name(self.input));
        match filesearch::get_rustpkg_sysroot() {
            Ok(r) => {
                let root = r.pop().pop().pop().pop(); // :-\
                debug!("Root is %s, calling compile_rest", root.to_str());
                let exe = self.build_dir.push(~"pkg" + util::exe_suffix());
                util::compile_crate_from_input(self.input, self.id,
                                               Some(self.build_dir),
                                               sess, Some(crate),
                                               exe, os::args()[0],
                                               driver::cu_everything);
                debug!("Running program: %s %s %s", exe.to_str(), root.to_str(), what);
                let status = run::run_program(exe.to_str(), ~[root.to_str(), what]);
                if status != 0 {
                    return (~[], status);
                }
                else {
                    debug!("Running program (configs): %s %s %s",
                           exe.to_str(), root.to_str(), ~"configs");
                    let output = run::program_output(exe.to_str(), ~[root.to_str(), ~"configs"]);
                    // Run the configs() function to get the configs
                    let mut cfgs = ~[];
                    for str::each_word(output.out) |w| {
                        cfgs.push(w.to_owned());
                    }
                    (cfgs, output.status)
                }
            }
            Err(e) => {
                fail!(fmt!("Running package script, couldn't find rustpkg sysroot (%s)",
                           e))
            }
        }
    }

    fn hash(&self) -> ~str {
        self.id.hash()
    }

}

struct Ctx {
    // I'm not sure what this is for
    json: bool,
    // Cache of hashes of things already installed
    // though I'm not sure why the value is a bool
    dep_cache: @mut HashMap<~str, bool>,
}

impl Ctx {

    fn run(&self, cmd: ~str, args: ~[~str]) {
        let root = util::root();

        util::need_dir(&root);
        util::need_dir(&root.push(~"work"));
        util::need_dir(&root.push(~"lib"));
        util::need_dir(&root.push(~"bin"));
        util::need_dir(&root.push(~"tmp"));

        fn sep_name_vers(in: ~str) -> (Option<~str>, Option<~str>) {
            let mut name = None;
            let mut vers = None;

            for str::each_split_char(in, '@') |s| {
                if      name.is_none() { name = Some(s.to_owned()); }
                else if vers.is_none() { vers = Some(s.to_owned()); }
                else                   { break;               }
            }

            (name, vers)
        }

        match cmd {
            ~"build" => {
                if args.len() < 1 {
                    return usage::build();
                }
                // The package id is presumed to be the first command-line
                // argument
                let pkgid = PkgId::new(args[0]);
                // Should allow the build directory to be configured.
                // Right now it's always the "build" subdirectory in
                // the package directory
                let dst_dir = dest_dir(pkgid);
                debug!("Destination dir = %s", dst_dir.to_str());
                // Right now, we assume the pkgid path is a valid dir
                // relative to the CWD. In the future, we should search
                // paths
                let cwd = os::getcwd().normalize();
                debug!("Current working directory = %s", cwd.to_str());

                // Create the package source
                let mut src = PkgSrc::new(&cwd, &dst_dir, &pkgid);
                debug!("Package src = %?", src);

                // Is there custom build logic? If so, use it
                let pkg_src_dir = cwd.push_rel(&pkgid.path);
                let mut custom = false;;
                debug!("Package source directory = %s", pkg_src_dir.to_str());
                let cfgs = match src.package_script_option(&pkg_src_dir) {
                    Some(package_script_path) => {
                        let pscript = PkgScript::parse(package_script_path,
                                                       pkgid);
                        // Limited right now -- we're only running the post_build
                        // hook and probably fail otherwise
                        // also post_build should be called pre_build
                        let (cfgs, hook_result) = pscript.run_custom(~"post_build");
                        debug!("Command return code = %?", hook_result);
                        if hook_result != 0 {
                            fail!(fmt!("Error running custom build command"))
                        }
                        custom = true;
                        // otherwise, the package script succeeded
                        cfgs
                    }
                    None => {
                        debug!("No package script, continuing");
                        ~[]
                    }
                };

                // Find crates inside the workspace
                if !custom {
                    src.find_crates();
                }

                // Build it!
                src.build(&dst_dir, cfgs);
            }
            ~"clean" => {
                self.clean();
            }
            ~"do" => {
                if args.len() < 2 {
                    return usage::do_cmd();
                }

                if !self.do_cmd(args[0], args[1]) {
                    fail!(~"a command failed!");
                }
            }
            ~"info" => {
                self.info();
            }
            ~"install" => {
                self.install(if args.len() >= 1 { Some(args[0]) }
                             else { None },
                             if args.len() >= 2 { Some(args[1]) }
                             else { None }, false);
            }
            ~"prefer" => {
                if args.len() < 1 {
                    return usage::uninstall();
                }

                let (name, vers) = sep_name_vers(args[0]);

                self.prefer(name.get(), vers);
            }
            ~"test" => {
                self.test();
            }
            ~"uninstall" => {
                if args.len() < 1 {
                    return usage::uninstall();
                }

                let (name, vers) = sep_name_vers(args[0]);

                self.uninstall(name.get(), vers);
            }
            ~"unprefer" => {
                if args.len() < 1 {
                    return usage::uninstall();
                }

                let (name, vers) = sep_name_vers(args[0]);

                self.unprefer(name.get(), vers);
            }
            _ => fail!(~"reached an unhandled command")
        }
    }

    fn do_cmd(&self, cmd: ~str, pkgname: ~str) -> bool {
        match cmd {
            ~"build" | ~"test" => {
                util::error(~"that command cannot be manually called");

                return false;
            }
            _ => {}
        }

        let cwd = &os::getcwd();
        let pkgid = PkgId::new(pkgname);
        // Always use the "build" subdirectory of the package dir,
        // but we should allow this to be configured
        let dst_dir = dest_dir(pkgid);

        let mut src = PkgSrc::new(cwd, &dst_dir, &pkgid);
        match src.package_script_option(cwd) {
            Some(script_path) => {
                let script = PkgScript::parse(script_path, pkgid);
                let (_, status) = script.run_custom(cmd); // Ignore cfgs?
                if status == 42 { // ???
                    util::error(~"no fns are listening for that cmd");
                    return false;
                }
                status == 0
            }
            None => {
                util::error(fmt!("invoked `do`, but there is no package script in %s",
                                 cwd.to_str()));
                false
            }
        }
    }

    fn build(&self, _dir: &Path, _verbose: bool, _opt: bool,
             _test: bool) -> Option<PkgScript> {
 // either not needed anymore,
 // or needed only when we don't have a package script. Not sure which one.
        fail!();
    }

    fn compile(&self, _crate: &Path, _dir: &Path, _flags: ~[~str],
               _cfgs: ~[~str], _opt: bool, _test: bool) -> bool {
        // What's the difference between build and compile?
        fail!(~"compile not yet implemented");
    }

    fn clean(&self) -> bool {
        // stub
        fail!();
    }

    fn info(&self) {
        // stub
        fail!();
    }

    fn install(&self, url: Option<~str>,
               target: Option<~str>, cache: bool) -> bool {
       let dir = match url {
            None => {
                util::note(~"installing from the cwd");
                os::getcwd()
            }
            Some(url) => {
                let hash = util::hash(if !target.is_none() {
                    url + target.get()
                }
                else { url });

                if self.dep_cache.contains_key(&hash) {
                    util::warn(~"already installed dep this run");
                    return true;
                }

                self.dep_cache.insert(hash, true);

                let dir = util::root().push(~"tmp").push(hash);

                if cache && os::path_exists(&dir) {
                    return true;
                }

                if !self.fetch(&dir, url, target) {
                    return false;
                }
                dir
            }
        };

        let script = match self.build(&dir, false, true, false) {
            Some(script) => script,
            None => {
                return false;
            }
        };
        let work_dir = script.build_dir;
        let from_bin_dir = work_dir.push(~"bin");
        let from_lib_dir = work_dir.push(~"lib");
        let to_bin_dir = util::root().push(~"bin");
        let to_lib_dir = util::root().push(~"lib");
        let mut bins = ~[];
        let mut libs = ~[];

        for os::walk_dir(&from_bin_dir) |bin| {
            let to = to_bin_dir.push_rel(&bin.file_path());

            os::copy_file(bin, &to);
            bins.push(to.to_str());
        }

        for os::walk_dir(&from_lib_dir) |lib| {
            let to = to_lib_dir.push_rel(&lib.file_path());

            os::copy_file(lib, &to);
            libs.push(to.to_str());
        }

        let package = Pkg {
            id: script.id,
            bins: bins,
            libs: libs
        };

        util::note(fmt!("installed %s", script.id.to_str()));
        util::add_pkg(&package);

        true
    }

    fn fetch(&self, dir: &Path, url: ~str, target: Option<~str>) -> bool {
        let url = if str::find_str(url, "://").is_none() {
            ~"http://" + url }
        else { url };
        let url = match url::from_str(url) {
            result::Ok(url) => url,
            result::Err(err) => {
                util::error(fmt!("failed parsing %s", err.to_lower()));

                return false;
            }
        };
        let str = url.to_str();

        match Path(url.path).filetype() {
            Some(ext) => {
                if ext == ~".git" {
                    return self.fetch_git(dir, str, target);
                }
            }
            None => {}
        }

        match url.scheme {
            ~"git" => self.fetch_git(dir, str, target),
            ~"http" | ~"ftp" | ~"file" => self.fetch_curl(dir, str),
            _ => {
                util::warn(~"unknown url scheme to fetch, using curl");
                self.fetch_curl(dir, str)
            }
        }
    }

    fn fetch_curl(&self, dir: &Path, url: ~str) -> bool {
        util::note(fmt!("fetching from %s using curl", url));

        let tar = dir.dir_path().push(&dir.file_path().to_str() + ~".tar");

        if run::program_output(~"curl", ~[~"-f", ~"-s",
                                          ~"-o", tar.to_str(),
                                          url]).status != 0 {
            util::error(~"fetching failed: downloading using curl failed");

            return false;
        }

        if run::program_output(~"tar", ~[~"-x", ~"--strip-components=1",
                                         ~"-C", dir.to_str(), ~"-f",
                                         tar.to_str()]).status != 0 {
            util::error(~"fetching failed: extracting using tar failed" +
                        ~"(is it a valid tar archive?)");

            return false;
        }

        true
    }

    fn fetch_git(&self, dir: &Path, url: ~str, target: Option<~str>) -> bool {
        util::note(fmt!("fetching from %s using git", url));

        // Git can't clone into a non-empty directory
        util::remove_dir_r(dir);

        if run::program_output(~"git", ~[~"clone", url,
                                         dir.to_str()]).status != 0 {
            util::error(~"fetching failed: can't clone repository");

            return false;
        }

        if !target.is_none() {
            let mut success = true;

            do util::temp_change_dir(dir) {
                success = run::program_output(~"git",
                                              ~[~"checkout",
                                                target.get()]).status != 0
            }

            if !success {
                util::error(~"fetching failed: can't checkout target");

                return false;
            }
        }

        true
    }

    fn prefer(&self, id: ~str, vers: Option<~str>) -> bool {
        let package = match util::get_pkg(id, vers) {
            result::Ok(package) => package,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };
        let name = package.id.path.to_str(); // ???

        util::note(fmt!("preferring %s v%s", name, package.id.version.to_str()));

        let bin_dir = util::root().push(~"bin");

        for package.bins.each |&bin| {
            let path = Path(bin);
            let mut name = None;
            for str::each_split_char(path.file_path().to_str(), '-') |s| {
                name = Some(s.to_owned());
                break;
            }
            let out = bin_dir.push(name.unwrap());

            util::link_exe(&path, &out);
            util::note(fmt!("linked %s", out.to_str()));
        }

        util::note(fmt!("preferred %s v%s", name, package.id.version.to_str()));

        true
    }

    fn test(&self) -> bool {
        let script = match self.build(&os::getcwd(), false, false, true) {
            Some(script) => script,
            None => {
                return false;
            }
        };

        // To do
        util::note(fmt!("Would test %s, but this is a dry run",
                        script.id.to_str()));
        false
    }

    fn uninstall(&self, _id: ~str, _vers: Option<~str>) -> bool {
        fail!(~"uninstall not yet implemented");
    }

    fn unprefer(&self, _id: ~str, _vers: Option<~str>) -> bool {
        fail!(~"unprefer not yet implemented");
    }
}

pub fn main() {
    io::println("WARNING: The Rust package manager is experimental and may be unstable");

    let args = os::args();
    let opts = ~[getopts::optflag(~"h"), getopts::optflag(~"help"),
                 getopts::optflag(~"j"), getopts::optflag(~"json"),
                 getopts::optmulti(~"c"), getopts::optmulti(~"cfg")];
    let matches = &match getopts::getopts(args, opts) {
        result::Ok(m) => m,
        result::Err(f) => {
            util::error(fmt!("%s", getopts::fail_str(f)));

            return;
        }
    };
    let help = getopts::opt_present(matches, ~"h") ||
               getopts::opt_present(matches, ~"help");
    let json = getopts::opt_present(matches, ~"j") ||
               getopts::opt_present(matches, ~"json");
    let mut args = copy matches.free;

    args.shift();

    if (args.len() < 1) {
        return usage::general();
    }

    let cmd = args.shift();

    if !util::is_cmd(cmd) {
        return usage::general();
    } else if help {
        return match cmd {
            ~"build" => usage::build(),
            ~"clean" => usage::clean(),
            ~"do" => usage::do_cmd(),
            ~"info" => usage::info(),
            ~"install" => usage::install(),
            ~"prefer" => usage::prefer(),
            ~"test" => usage::test(),
            ~"uninstall" => usage::uninstall(),
            ~"unprefer" => usage::unprefer(),
            _ => usage::general()
        };
    }

    Ctx {
        json: json,
        dep_cache: @mut HashMap::new()
    }.run(cmd, args);
}

/// A crate is a unit of Rust code to be compiled into a binary or library
pub struct Crate {
    file: Path,
    flags: ~[~str],
    cfgs: ~[~str]
}

pub struct Listener {
    cmds: ~[~str],
    cb: ~fn()
}

pub fn run(listeners: ~[Listener]) {
    let rcmd = os::args()[2];
    let mut found = false;

    for listeners.each |listener| {
        for listener.cmds.each |&cmd| {
            if cmd == rcmd {
                (listener.cb)();

                found = true;

                break;
            }
        }
    }

    if !found {
        os::set_exit_status(42);
    }
}

pub impl Crate {

    fn new(p: &Path) -> Crate {
        Crate {
            file: copy *p,
            flags: ~[],
            cfgs: ~[]
        }
    }

    fn flag(&self, flag: ~str) -> Crate {
        Crate {
            flags: vec::append(copy self.flags, ~[flag]),
            .. copy *self
        }
    }

    fn flags(&self, flags: ~[~str]) -> Crate {
        Crate {
            flags: vec::append(copy self.flags, flags),
            .. copy *self
        }
    }

    fn cfg(&self, cfg: ~str) -> Crate {
        Crate {
            cfgs: vec::append(copy self.cfgs, ~[cfg]),
            .. copy *self
        }
    }

    fn cfgs(&self, cfgs: ~[~str]) -> Crate {
        Crate {
            cfgs: vec::append(copy self.cfgs, cfgs),
            .. copy *self
        }
    }
}

/**
 * Get the working directory of the package script.
 * Assumes that the package script has been compiled
 * in is the working directory.
 */
pub fn work_dir() -> Path {
    os::self_exe_path().get()
}

/**
 * Get the source directory of the package (i.e.
 * where the crates are located). Assumes
 * that the cwd is changed to it before
 * running this executable.
 */
pub fn src_dir() -> Path {
    os::getcwd()
}

condition! {
    bad_pkg_id: (super::Path, ~str) -> ::util::PkgId;
}

// An enumeration of the unpacked source of a package workspace.
// This contains a list of files found in the source workspace.
pub struct PkgSrc {
    root: Path, // root of where the package source code lives
    dst_dir: Path, // directory where we will put the compiled output
    id: PkgId,
    libs: ~[Crate],
    mains: ~[Crate],
    tests: ~[Crate],
    benchs: ~[Crate],
}

condition! {
    build_err: (~str) -> ();
}

impl PkgSrc {

    fn new(src_dir: &Path, dst_dir: &Path,
                  id: &PkgId) -> PkgSrc {
        PkgSrc {
            root: copy *src_dir,
            dst_dir: copy *dst_dir,
            id: copy *id,
            libs: ~[],
            mains: ~[],
            tests: ~[],
            benchs: ~[]
        }
    }


    fn check_dir(&self) -> Path {
        use conditions::bad_path::cond;

        debug!("Pushing onto root: %s | %s", self.id.path.to_str(),
               self.root.to_str());

        let dir = self.root.push_rel(&self.id.path).normalize();

        debug!("Checking dir: %s", dir.to_str());

        if !os::path_exists(&dir) {
            return cond.raise((dir, ~"missing package dir"));
        }

        if !os::path_is_dir(&dir) {
            return cond.raise((dir, ~"supplied path for package dir is a \
                                      non-directory"));
        }

        dir
    }

    // If a file named "pkg.rs" in the current directory exists,
    // return the path for it. Otherwise, None
    fn package_script_option(&self, cwd: &Path) -> Option<Path> {
        let maybe_path = cwd.push("pkg.rs");
        if os::path_exists(&maybe_path) {
            Some(maybe_path)
        }
        else {
            None
        }
    }

    /// True if the given path's stem is self's pkg ID's stem
    /// or if the pkg ID's stem is <rust-foo> and the given path's
    /// stem is foo
    /// Requires that dashes in p have already been normalized to
    /// underscores
    fn stem_matches(&self, p: &Path) -> bool {
        let self_id = normalize(~self.id.path).filestem();
        if self_id == p.filestem() {
            return true;
        }
        else {
            for self_id.each |pth| {
                if pth.starts_with("rust_") // because p is already normalized
                    && match p.filestem() {
                           Some(s) => str::eq_slice(s, pth.slice(5, pth.len())),
                           None => false
                       } { return true; }
            }
        }
        false
    }

    fn push_crate(cs: &mut ~[Crate], prefix: uint, p: &Path) {
        assert!(p.components.len() > prefix);
        let mut sub = Path("");
        for vec::slice(p.components, prefix,
                       p.components.len()).each |c| {
            sub = sub.push(*c);
        }
        debug!("found crate %s", sub.to_str());
        cs.push(Crate::new(&sub));
    }

    /// Infers crates to build. Called only in the case where there
    /// is no custom build logic
    fn find_crates(&mut self) {
        use PkgSrc::push_crate;

        let dir = self.check_dir();
        let prefix = dir.components.len();
        debug!("Matching against %?", self.id.path.filestem());
        for os::walk_dir(&dir) |pth| {
            match pth.filename() {
                Some(~"lib.rs") => push_crate(&mut self.libs,
                                              prefix, pth),
                Some(~"main.rs") => push_crate(&mut self.mains,
                                               prefix, pth),
                Some(~"test.rs") => push_crate(&mut self.tests,
                                               prefix, pth),
                Some(~"bench.rs") => push_crate(&mut self.benchs,
                                                prefix, pth),
                _ => {
                    util::note(~"Couldn't infer any crates to build.\n\
                                Try naming a crate `main.rs`, `lib.rs`, \
                                `test.rs`, or `bench.rs`.");
                    fail!(~"Failed to infer crates to build");
                }
            }
        }
        debug!("found %u libs, %u mains, %u tests, %u benchs",
               self.libs.len(),
               self.mains.len(),
               self.tests.len(),
               self.benchs.len())
    }

    fn build_crates(&self, dst_dir: &Path,
                           src_dir: &Path,
                           crates: &[Crate],
                           cfgs: ~[~str],
                           test: bool, crate_type: crate_type) {

        for crates.each |&crate| {
            let path = &src_dir.push_rel(&crate.file).normalize();
            util::note(fmt!("build_crates: compiling %s", path.to_str()));
            util::note(fmt!("build_crates: destination dir is %s", dst_dir.to_str()));

            let result = util::compile_crate(None, self.id, path,
                                     dst_dir,
                                     crate.flags,
                                     crate.cfgs + cfgs,
                                     false, test, crate_type);
            if !result {
                build_err::cond.raise(fmt!("build failure on %s",
                                           path.to_str()));
            }
            debug!("Result of compiling %s was %?",
                   path.to_str(), result);
        }
    }

    fn build(&self, dst_dir: &Path, cfgs: ~[~str]) {
        let dir = self.check_dir();
        debug!("Building libs");
        self.build_crates(dst_dir, &dir, self.libs, cfgs, false, lib_crate);
        debug!("Building mains");
        self.build_crates(dst_dir, &dir, self.mains, cfgs, false, bin_crate);
        debug!("Building tests");
        self.build_crates(dst_dir, &dir, self.tests, cfgs, true, bin_crate);
        debug!("Building benches");
        self.build_crates(dst_dir, &dir, self.benchs, cfgs, true, bin_crate);
    }
}