#![feature(box_syntax)]
#![feature(box_patterns)]
#![feature(specialization)]
#![feature(test)]

extern crate test;

use std::{
    env,
    fs::{read_dir, File},
    io::{self, Read},
    path::Path,
};
use swc_common::{Fold, FoldWith, Span};
use swc_ecma_ast::*;
use swc_ecma_parser::{lexer::Lexer, PResult, Parser, Session, SourceFileInput, Syntax};
use test::{
    test_main, DynTestFn, Options, ShouldPanic::No, TestDesc, TestDescAndFn, TestName, TestType,
};
use testing::{NormalizedOutput, StdErr};

const IGNORED_PASS_TESTS: &[&str] = &[
    // Temporalily ignored
    "431ecef8c85d4d24.js",
    "8386fbff927a9e0e.js",
    "5654d4106d7025c2.js",
    // Stack size (Stupid parens)
    "6b5e7e125097d439.js",
    "714be6d28082eaa7.js",
    "882910de7dd1aef9.js",
    "dd3c63403db5c06e.js",
    // Static constructor
    "dcc5609dcc043200.js",
    "88d42455ac933ef5.js",
    // Wrong tests (variable name or value is different)
    "0339fa95c78c11bd.js",
    "0426f15dac46e92d.js",
    "0b4d61559ccce0f9.js",
    "0f88c334715d2489.js",
    "1093d98f5fc0758d.js",
    "15d9592709b947a0.js",
    "2179895ec5cc6276.js",
    "247a3a57e8176ebd.js",
    "441a92357939904a.js",
    "47f974d6fc52e3e4.js",
    "4e1a0da46ca45afe.js",
    "5829d742ab805866.js",
    "589dc8ad3b9aa28f.js",
    "598a5cedba92154d.js",
    "72d79750e81ef03d.js",
    "7788d3c1e1247da9.js",
    "7b72d7b43bedc895.js",
    "7dab6e55461806c9.js",
    "82c827ccaecbe22b.js",
    "87a9b0d1d80812cc.js",
    "8c80f7ee04352eba.js",
    "96f5d93be9a54573.js",
    "988e362ed9ddcac5.js",
    "9bcae7c7f00b4e3c.js",
    "a8a03a88237c4e8f.js",
    "ad06370e34811a6a.js",
    "b0fdc038ee292aba.js",
    "b62c6dd890bef675.js",
    "cb211fadccb029c7.js",
    "ce968fcdf3a1987c.js",
    "db3c01738aaf0b92.js",
    "e1387fe892984e2b.js",
    "e71c1d5f0b6b833c.js",
    "e8ea384458526db0.js",
    // We don't implement Annex B fully.
    "1c1e2a43fe5515b6.js",
    "3dabeca76119d501.js",
    "52aeec7b8da212a2.js",
    "59ae0289778b80cd.js",
    "a4d62a651f69d815.js",
    "c06df922631aeabc.js",
    // Wrong test - strict mode
    "8f8bfb27569ac008.js",
    "ce569e89a005c02a.js",
];

fn add_test<F: FnOnce() + Send + 'static>(
    tests: &mut Vec<TestDescAndFn>,
    name: String,
    ignore: bool,
    f: F,
) {
    tests.push(TestDescAndFn {
        desc: TestDesc {
            test_type: TestType::UnitTest,
            name: TestName::DynTestName(name),
            ignore,
            should_panic: No,
            allow_fail: false,
        },
        testfn: DynTestFn(box f),
    });
}

fn error_tests(tests: &mut Vec<TestDescAndFn>) -> Result<(), io::Error> {
    const IGNORED_ERROR_TESTS: &[&str] = &[
        // Old (wrong) tests
        "569a2c1bad3beeb2.js",
        // Wrong tests
        "0d5e450f1da8a92a.js",
        "346316bef54d805a.js",
        "976b6247ca78ab51.js",
        "ae0a7ac275bc9f5c.js",
        "748656edbfb2d0bb.js",
        "79f882da06f88c9f.js",
        "d28e80d99f819136.js",
        "92b6af54adef3624.js",
        "ef2d369cccc5386c.js",
        // Temporarily ignore tests for using octal escape before use strict
        "147fa078a7436e0e.js",
        "15a6123f6b825c38.js",
        "3bc2b27a7430f818.js",
        // Tmporarily ignored
        "3dbb6e166b14a6c0.js",
        "66e383bfd18e66ab.js",
        "78c215fabdf13bae.js",
        "bf49ec8d96884562.js",
        "e4a43066905a597b.js",
    ];

    let root = {
        let mut root = Path::new(env!("CARGO_MANIFEST_DIR")).to_path_buf();
        root.push("tests");
        root.push("test262-parser");
        root
    };

    eprintln!("Loading tests from {}", root.display());

    const TYPES: &[&str] = &[
        "fail", /* TODO
                * "early" */
    ];

    for err_type in TYPES {
        let dir = root.join(err_type);
        let error_reference_dir = {
            let mut root = Path::new(env!("CARGO_MANIFEST_DIR")).to_path_buf();
            root.push("tests");
            root.push("test262-error-references");
            root.push(err_type);
            root
        };

        for entry in read_dir(&dir)? {
            let entry = entry?;
            let file_name = entry
                .path()
                .strip_prefix(&dir)
                .expect("failed to strip prefix")
                .to_str()
                .unwrap()
                .to_string();

            let input = {
                let mut buf = String::new();
                File::open(entry.path())?.read_to_string(&mut buf)?;
                buf
            };

            let ignore = IGNORED_ERROR_TESTS.contains(&&*file_name);

            let module = file_name.contains("module");

            let dir = dir.clone();
            let error_reference_dir = error_reference_dir.clone();
            let name = format!("test262::error_reporting::{}::{}", err_type, file_name);
            add_test(tests, name, ignore, move || {
                eprintln!(
                    "\n\n========== Running error reporting test {}\nSource:\n{}\n",
                    file_name, input
                );

                let path = dir.join(&file_name);
                // Parse source
                let err = if module {
                    parse_module(&path).expect_err("should fail, but parsed as")
                } else {
                    parse_script(&path).expect_err("should fail, but parsed as")
                };

                if err
                    .compare_to_file(format!(
                        "{}.stderr",
                        error_reference_dir.join(file_name).display()
                    ))
                    .is_err()
                {
                    panic!()
                }
            });
        }
    }

    Ok(())
}

fn identity_tests(tests: &mut Vec<TestDescAndFn>) -> Result<(), io::Error> {
    let root = {
        let mut root = Path::new(env!("CARGO_MANIFEST_DIR")).to_path_buf();
        root.push("tests");
        root.push("test262-parser");
        root
    };

    eprintln!("Loading tests from {}", root.display());

    let pass_dir = root.join("pass");

    let files = read_dir(&pass_dir)?;

    for entry in files {
        let entry = entry?;
        let file_name = entry
            .path()
            .strip_prefix(&pass_dir)
            .expect("failed to strip prefix")
            .to_str()
            .unwrap()
            .to_string();

        let input = {
            let mut buf = String::new();
            File::open(entry.path())?.read_to_string(&mut buf)?;
            buf
        };
        let explicit = {
            let mut buf = String::new();
            File::open(root.join("pass-explicit").join(&file_name))?.read_to_string(&mut buf)?;
            buf
        };

        let ignore = IGNORED_PASS_TESTS.contains(&&*file_name);

        let module = file_name.contains("module");

        let root = root.clone();
        let name = format!("test262::identity::{}", file_name);
        add_test(tests, name, ignore, move || {
            eprintln!(
                "\n\n\n========== Running test {}\nSource:\n{}\nExplicit:\n{}",
                file_name, input, explicit
            );

            if module {
                let p = |explicit| {
                    parse_module(
                        &root
                            .join(if explicit { "pass-explicit" } else { "pass" })
                            .join(&file_name),
                    )
                    .map(normalize)
                    .unwrap()
                };
                let src = p(false);
                let expected = p(true);
                assert_eq!(src, expected);

                let json =
                    serde_json::to_string_pretty(&src).expect("failed to serialize module as json");

                let deser = serde_json::from_str::<Module>(&json)
                    .unwrap_or_else(|err| {
                        panic!(
                            "failed to deserialize json back to module: {}\n{}",
                            err, json
                        )
                    })
                    .fold_with(&mut Normalizer);
                assert_eq!(src, deser, "JSON:\n{}", json);
            } else {
                let p = |explicit| {
                    parse_script(
                        &root
                            .join(if explicit { "pass-explicit" } else { "pass" })
                            .join(&file_name),
                    )
                    .map(normalize)
                    .unwrap()
                };
                let src = p(false);
                let expected = p(true);
                assert_eq!(src, expected);
            }
        });
    }

    Ok(())
}

fn parse_script(file_name: &Path) -> Result<Script, NormalizedOutput> {
    with_parser(file_name, |p| p.parse_script())
}
fn parse_module<'a>(file_name: &Path) -> Result<Module, NormalizedOutput> {
    with_parser(file_name, |p| p.parse_module())
}

fn with_parser<F, Ret>(file_name: &Path, f: F) -> Result<Ret, StdErr>
where
    F: for<'a> FnOnce(&mut Parser<'a, Lexer<'a, SourceFileInput<'_>>>) -> PResult<'a, Ret>,
{
    let output = ::testing::run_test(false, |cm, handler| {
        let fm = cm
            .load_file(file_name)
            .unwrap_or_else(|e| panic!("failed to load {}: {}", file_name.display(), e));

        let res = f(&mut Parser::new(
            Session { handler: &handler },
            Syntax::default(),
            (&*fm).into(),
            None,
        ))
        .map_err(|mut e| {
            e.emit();
        });

        if handler.has_errors() {
            return Err(());
        }

        res
    });

    output
}

#[test]
fn identity() {
    let args: Vec<_> = env::args().collect();
    let mut tests = Vec::new();
    identity_tests(&mut tests).unwrap();
    test_main(&args, tests, Some(Options::new()));
}

#[test]
fn error() {
    let args: Vec<_> = env::args().collect();
    let mut tests = Vec::new();
    error_tests(&mut tests).unwrap();
    test_main(&args, tests, Some(Options::new()));
}

pub fn normalize<T>(t: T) -> T
where
    Normalizer: Fold<T>,
{
    let mut n = Normalizer;
    n.fold(t)
}

pub struct Normalizer;
impl Fold<Span> for Normalizer {
    fn fold(&mut self, _: Span) -> Span {
        Span::default()
    }
}
impl Fold<Str> for Normalizer {
    fn fold(&mut self, s: Str) -> Str {
        Str {
            span: Default::default(),
            has_escape: false,
            ..s
        }
    }
}
impl Fold<Expr> for Normalizer {
    fn fold(&mut self, e: Expr) -> Expr {
        let e = e.fold_children(self);

        match e {
            Expr::Paren(ParenExpr { expr, .. }) => *expr,
            Expr::New(n @ NewExpr { args: None, .. }) => Expr::New(NewExpr {
                args: Some(vec![]),
                ..n
            }),
            // Flatten comma expressions.
            Expr::Seq(SeqExpr { mut exprs, span }) => {
                let need_work = exprs.iter().any(|n| match **n {
                    Expr::Seq(..) => true,
                    _ => false,
                });

                if need_work {
                    exprs = exprs.into_iter().fold(vec![], |mut v, e| {
                        match *e {
                            Expr::Seq(SeqExpr { exprs, .. }) => v.extend(exprs),
                            _ => v.push(e),
                        }
                        v
                    });
                }
                Expr::Seq(SeqExpr { exprs, span })
            }
            _ => e,
        }
    }
}

impl Fold<PropName> for Normalizer {
    fn fold(&mut self, n: PropName) -> PropName {
        let n = n.fold_children(self);

        match n {
            PropName::Ident(Ident { sym, .. }) => PropName::Str(Str {
                span: Default::default(),
                value: sym,
                has_escape: false,
            }),
            PropName::Num(num) => PropName::Str(Str {
                span: Default::default(),
                value: num.to_string().into(),
                has_escape: false,
            }),
            _ => n,
        }
    }
}

impl Fold<PatOrExpr> for Normalizer {
    fn fold(&mut self, node: PatOrExpr) -> PatOrExpr {
        let node = node.fold_children(self);

        match node {
            PatOrExpr::Pat(box Pat::Expr(e)) => PatOrExpr::Expr(e),
            PatOrExpr::Expr(box Expr::Ident(i)) => PatOrExpr::Pat(box Pat::Ident(i)),
            _ => node,
        }
    }
}