extern crate serde;
#[macro_use]
extern crate serde_derive;
// This allows inserting JSON documents
#[macro_use]
extern crate serde_json;
extern crate ledb;
// This allows define typed documents easy
#[macro_use]
extern crate ledb_derive;
extern crate ledb_types;
extern crate zip;

use clap::{Parser, Subcommand};
use rand::seq::IteratorRandom;
use std::path::PathBuf;
use std::time::Instant;
use std::{fs, io};

use ledb::{Options, Storage};

macro_rules! make {
    ($Target:ident; by {$($field:ident),+}; from $src:expr) => {$Target {$(
        $field: $src.$field
    ),+}};
    ($Target:ident; with defaults and by {$($field:ident),+}; from $src:expr) => {$Target {$(
        $field: $src.$field
    ),+ ,..$Target::default()}}
}

#[derive(Subcommand, Debug)]
enum Command {
    Write,
    Compact,
    Print {
        #[clap(value_parser, default_value = "0")]
        id: u32,
    },
    ZipPrint {
        #[clap(value_parser, default_value = "0")]
        file_num: usize,
        #[clap(value_parser, default_value = "0")]
        num: usize,
    },
}

#[derive(Parser, Debug)]
#[clap(author, version, about, long_about = None)]
#[clap(propagate_version = true)]
struct Cli {
    #[clap(subcommand)]
    command: Command,
    #[clap(short, long, action)]
    measure: bool,
}

#[derive(Debug, Default, Clone, Serialize, Deserialize)]
struct SourceQuestion {
    #[serde(default)]
    num: u32,
    id: String,

    #[serde(alias = "Вопрос")]
    description: String,
    #[serde(alias = "Ответ")]
    answer: String,

    #[serde(alias = "Автор")]
    #[serde(default)]
    author: String,
    #[serde(alias = "Комментарий")]
    #[serde(default)]
    comment: String,
    #[serde(alias = "Комментарии")]
    #[serde(alias = "Инфо")]
    #[serde(default)]
    comment1: String,
    #[serde(alias = "Тур")]
    #[serde(default)]
    tour: String,
    #[serde(alias = "Ссылка")]
    #[serde(alias = "URL")]
    #[serde(default)]
    url: String,
    #[serde(alias = "Дата")]
    #[serde(default)]
    date: String,
    #[serde(alias = "Обработан")]
    #[serde(default)]
    processed_by: String,
    #[serde(alias = "Редактор")]
    #[serde(default)]
    redacted_by: String,
    #[serde(alias = "Копирайт")]
    #[serde(default)]
    copyright: String,
    #[serde(alias = "Тема")]
    #[serde(default)]
    theme: String,
    #[serde(alias = "Вид")]
    #[serde(alias = "Тип")]
    #[serde(default)]
    kind: String,
    #[serde(alias = "Источник")]
    #[serde(default)]
    source: String,
    #[serde(alias = "Рейтинг")]
    #[serde(default)]
    rating: String,
}

#[derive(Debug, Default, Clone, Serialize, Deserialize)]
struct SourceQuestionsBatch {
    #[serde(default)]
    filename: String,
    #[serde(alias = "Пакет")]
    #[serde(alias = "Чемпионат")]
    description: String,
    #[serde(alias = "Автор")]
    #[serde(default)]
    author: String,
    #[serde(alias = "Комментарий")]
    #[serde(alias = "Комментарии")]
    #[serde(alias = "Инфо")]
    #[serde(default)]
    comment: String,
    #[serde(alias = "Ссылка")]
    #[serde(alias = "URL")]
    #[serde(default)]
    url: String,
    #[serde(alias = "Дата")]
    #[serde(default)]
    date: String,
    #[serde(alias = "Обработан")]
    #[serde(default)]
    processed_by: String,
    #[serde(alias = "Редактор")]
    #[serde(default)]
    redacted_by: String,
    #[serde(alias = "Копирайт")]
    #[serde(default)]
    copyright: String,
    #[serde(alias = "Тема")]
    #[serde(default)]
    theme: String,
    #[serde(alias = "Вид")]
    #[serde(alias = "Тип")]
    #[serde(default)]
    kind: String,
    #[serde(alias = "Источник")]
    #[serde(default)]
    source: String,
    #[serde(alias = "Рейтинг")]
    #[serde(default)]
    rating: String,
    #[serde(alias = "Вопросы")]
    questions: Vec<SourceQuestion>,
}

#[derive(Debug, Default, Clone, Serialize, Deserialize, Document)]
struct BatchInfo {
    #[document(primary)]
    #[serde(default)]
    filename: String,
    #[serde(default)]
    description: String,
    #[serde(default)]
    author: String,
    #[serde(default)]
    comment: String,
    #[serde(default)]
    url: String,
    #[serde(default)]
    date: String,
    #[serde(default)]
    processed_by: String,
    #[serde(default)]
    redacted_by: String,
    #[serde(default)]
    copyright: String,
    #[serde(default)]
    theme: String,
    #[serde(default)]
    kind: String,
    #[serde(default)]
    source: String,
    #[serde(default)]
    rating: String,
}

#[derive(Debug, Default, Clone, Serialize, Deserialize, Document)]
struct Question {
    #[document(primary)]
    #[serde(default)]
    num: u32,
    #[document(index)]
    id: String,

    description: String,
    answer: String,

    #[serde(default)]
    author: String,
    #[serde(default)]
    comment: String,
    #[serde(default)]
    comment1: String,
    #[serde(default)]
    tour: String,
    #[serde(default)]
    url: String,
    #[serde(default)]
    date: String,
    #[serde(default)]
    processed_by: String,
    #[serde(default)]
    redacted_by: String,
    #[serde(default)]
    copyright: String,
    #[serde(default)]
    theme: String,
    #[serde(default)]
    kind: String,
    #[serde(default)]
    source: String,
    #[serde(default)]
    rating: String,
    #[document(nested)]
    #[serde(default)]
    batch_info: BatchInfo,
}

impl From<SourceQuestion> for Question {
    fn from(src: SourceQuestion) -> Self {
        make! {Self; with defaults and by {
            num, id, description, answer, author, comment, comment1, tour, url,
            date, processed_by, redacted_by, copyright, theme, kind, source, rating
        }; from src}
    }
}

impl From<SourceQuestionsBatch> for BatchInfo {
    fn from(src: SourceQuestionsBatch) -> Self {
        make! {Self; by {
            filename, description, author, comment, url, date,
            processed_by, redacted_by, copyright, theme, kind, source, rating
        }; from src}
    }
}

impl From<SourceQuestionsBatch> for Vec<Question> {
    fn from(src: SourceQuestionsBatch) -> Self {
        let mut result: Vec<Question> = src
            .questions
            .iter()
            .map(|item| item.clone().into())
            .collect();
        let batch_info = BatchInfo::from(src);
        result.iter_mut().for_each(|mut question| {
            question.batch_info = batch_info.clone();
        });

        result
    }
}

// measure and return time elapsed in `func` in seconds
pub fn measure<F: FnOnce()>(func: F) -> f64 {
    let start = Instant::now();
    func();
    let elapsed = start.elapsed();
    (elapsed.as_secs() as f64) + (elapsed.subsec_nanos() as f64 / 1_000_000_000.0)
}

pub fn measure_and_print<F: FnOnce()>(func: F) {
    let m = measure(func);
    eprintln!("{}", m);
}

fn writer_v4() {
    const IN_FILENAME: &str = "test1.zip";
    const OUT_DIR: &str = "db";

    let out_file: PathBuf = [OUT_DIR, "data.mdb"].into_iter().collect();
    match fs::metadata(&out_file) {
        Ok(x) if x.is_file() => {
            fs::remove_file(&out_file).unwrap();
            println!(r#""{}" removed"#, out_file.to_str().unwrap());
        }
        _ => {}
    };

    let zip_file = fs::File::open(IN_FILENAME).unwrap();
    let zip_reader = io::BufReader::new(zip_file);
    let mut archive = zip::ZipArchive::new(zip_reader).unwrap();

    let options: Options = serde_json::from_value(json!({
        "map_size": 900 * 1024 * 1024, // 900mb
        "write_map": true,
        "map_async": true,
        "no_lock": true,
        "no_meta_sync": true,
        "no_sync": true,
    }))
    .unwrap();

    let storage = Storage::new("db", options).unwrap();
    let collection = storage.collection("questions").unwrap();

    println!("converting...");

    let mut count: usize = 0;
    let count = &mut count;
    (0..archive.len())
        .map(|i| {
            let file = archive.by_index(i).unwrap();
            let name = file.mangled_name();
            let name_str = name.to_str().unwrap();

            let data: Result<SourceQuestionsBatch, _> = serde_json::from_reader(file);

            (String::from(name_str), data)
        })
        .filter(|(_, data)| data.is_ok())
        .flat_map(|(filename, data)| {
            let mut data = data.unwrap();
            data.filename = filename;
            let questions: Vec<Question> = data.into();
            questions
        })
        .for_each(|question| {
            let result = collection.insert(&question);
            if result.is_err() {
                println!("-- {:#?}", question);
                panic!("-- {:#?}", result);
            } else {
                *count += 1;
            }
        });

    println!("inserted {}\nwriting...", count);
    storage.sync(true).unwrap();
    print!("stats: ");
    let stats = storage.stat().unwrap();
    println!("{:?}", stats);
    drop(storage);
}

fn print_question_from<F>(get_q: F)
where
    F: FnOnce() -> Option<Question>,
{
    let q = get_q().unwrap();
    println!("{:#?}", q)
}

fn reader_v1(mut file_num: usize, mut num: usize) -> Option<Question> {
    let zip_file = fs::File::open("test1.zip").unwrap();
    let zip_reader = io::BufReader::new(zip_file);
    let mut archive = zip::ZipArchive::new(zip_reader).unwrap();

    let mut rng = rand::thread_rng();
    if file_num == 0 {
        file_num = (1..=archive.len()).choose(&mut rng).unwrap();
    }
    let file = archive.by_index(file_num - 1).unwrap();
    let data: Result<SourceQuestionsBatch, _> = serde_json::from_reader(file);
    let data = data.unwrap();
    let questions: Vec<Question> = data.into();

    if num == 0 {
        num = (1..=questions.len()).choose(&mut rng).unwrap();
    }
    Some(questions[num - 1].clone())
}

fn compact_db() {
    let options: Options = serde_json::from_value(json!({
        "write_map": true,
        "map_async": true,
        "no_lock": true,
        "no_meta_sync": true,
        "no_sync": true,
        "compact": true,
    }))
    .unwrap();

    let storage = Storage::new("db", options).unwrap();

    storage.sync(true).unwrap();
    let stats = storage.stat().unwrap();
    println!("{:?}", stats);
    drop(storage);
}

fn reader_v4(mut id: u32) -> Option<Question> {
    let options: Options = serde_json::from_value(json!({
            "read_only": true,
    //        "map_async": true,
            "no_lock": true,
    //        "no_meta_sync": true,
    //        "no_sync": true,
    //        "no_tls": true
        }))
    .unwrap();

    let storage = Storage::new("db", options).unwrap();
    let collection = storage.collection("questions").unwrap();
    let mut rng = rand::thread_rng();

    if id == 0 {
        let last_id = collection.last_id().unwrap();
        id = (1..=last_id).choose(&mut rng).unwrap();
        //let id = ledb::KeyData::Int(id as i64);
    }

    collection.get::<Question>(id).unwrap()
}

fn main() {
    let args = Cli::parse();

    let mut action: Box<dyn FnOnce()> = match &args.command {
        Command::Write => Box::new(writer_v4),
        Command::Compact => Box::new(compact_db),
        Command::Print { id } => {
            let get_question = Box::new(|| reader_v4(*id));
            Box::new(|| print_question_from(get_question))
        }
        Command::ZipPrint { file_num, num } => {
            let get_question = Box::new(|| reader_v1(*file_num, *num));
            Box::new(|| print_question_from(get_question))
        }
    };

    if args.measure {
        action = Box::new(|| measure_and_print(action));
    }

    action();
}

/*

#[cfg(test)]
mod tests {
    use super::*;
    use test::Bencher;

    #[test]
    fn reader_v1_works() {
        reader_v1().unwrap();
    }
    fn reader_v4_works() {
        reader_v4().unwrap();
    }

    #[bench]
    fn bench_reader_v1(b: &mut Bencher) {
        b.iter(|| reader_v1());
    }

    #[bench]
    fn bench_reader_v4(b: &mut Bencher) {
        b.iter(|| reader_v4());
    }
}
*/