use std::process;
use std::env;
use std::fs::{read_dir, File};
use std::collections::HashMap;
use namegen_compiler::manifest::Manifest;
use std::env::join_paths;
use std::path::Path;
use namegen_compiler::input::SourceCollection;
use glob::glob;
use std::io::{Read};
use namegen::{Name, NamePart};
use namegen_compiler::output::{Output, Collection, CollectionItem};

const COMMON_FORMAT_NAMES: &'static [&str] = &[
    "full_name", "full_name:female", "full_name:male",
];

fn main() {
    let source_dir = match env::var("SOURCE_DIR") {
        Ok(v) => v,
        Err(_) => {
            eprintln!("SOURCE_DIR missing");
            process::exit(1);
        }
    };

    let dest_dir = match env::var("DESTINATION_DIR") {
        Ok(v) => v,
        Err(_) => {
            eprintln!("DESTINATION_DIR missing");
            process::exit(1);
        }
    };

    let mut data = String::with_capacity(2048);
    let mut collection = Collection{items: Vec::new()};

    for entry in read_dir(&source_dir).unwrap() {
        let entry = entry.unwrap();
        if !entry.file_type().unwrap().is_file() {
            continue;
        }

        let path = Path::new(&source_dir).join(entry.file_name());
        if path.to_str().unwrap().contains(".drone.yml") {
            continue;
        }

        eprintln!("Loading manifest {}", path.to_str().unwrap());

        let manifest: Manifest = serde_yaml::from_reader(File::open(path.clone()).unwrap()).unwrap();

        let mut coll = SourceCollection::default();
        for source in manifest.sources.iter() {
            let path = path.with_file_name(&source.files);

            for entry in glob(path.to_str().unwrap()).expect("Failed to read glob pattern") {
                let path = entry.expect("Invalid file entry.");

                data.clear();
                File::open(path.clone()).unwrap().read_to_string(&mut data);

                eprintln!("Loading source {} (size: {})", path.clone().to_str().unwrap(), data.len());

                match source.kind.as_str() {
                    "full_names" => { coll.load_full_names(&data, source).unwrap() }
                    "labeled_groups" => { coll.load_labeled_groups(&data, source).unwrap() }
                    _ => {
                        eprintln!("Unknown source file kind {}", source.kind);
                        process::exit(1);
                    }
                }
            }
        }

        let mut name = Name::new();

        for part in manifest.parts.iter() {
            eprintln!("Building part {}...", &part.name);

            let source = coll.source(&part.source).expect("Source not found.");
            let mut part = match part.kind.as_str() {
                "cfgrammar" => NamePart::new_cfgrammar(
                    &part.name, &part.format_rules, &part.initial_tokens,
                    part.rules.rlf, part.rules.ral,
                ),
                "markov" => NamePart::new_markov(
                    &part.name, &part.format_rules, &part.initial_tokens,
                    part.rules.lrs, part.rules.lrm, part.rules.lre, part.rules.rlf,
                ),
                "wordlist" => NamePart::new_wordlist(
                    &part.name, &part.format_rules
                ),

                _ => {
                    eprintln!("Unknown part kind {}", &part.kind);
                    process::exit(1);
                },
            };

            for set in source.sets() {
                if set.labels().len() == 0 {
                    eprintln!("\tSample list: {} samples", set.samples().len());
                } else {
                    eprintln!("\tSample group: {}", set.labels().join(" "));
                }
                part.learn(set).unwrap()
            }

            name.add_part(part);
        }

        for format in manifest.formats.iter() {
            name.add_format(&format.name, &format.template)
        }

        let mut examples = HashMap::new();
        for format in name.formats() {
            if let Some(gen) = name.generate(format.name()) {
		examples.insert(format.name().to_owned(), Vec::with_capacity(40));

                for (i, result) in gen.enumerate().take(40) {
                   examples.get_mut(format.name()).unwrap().push(result);
                }
            }
        }

        eprint!("\n");
        eprintln!("Sample output");
        for format_name in COMMON_FORMAT_NAMES.iter() {
            if let Some(gen) = name.generate(format_name) {
                eprint!("\n    ");

                for (i, result) in gen.enumerate().take(72) {
                    eprint!("{result:<width$} ", result = result, width = 19);
                    if i > 0 && (i % 4 == 3) {
                        eprint!("\n    ");
                    }
                }

                eprint!("\n");
            }
        }

        if let Some(gen) = name.generate("long_full_name:male") {
            eprint!("\n    ");

            for (i, result) in gen.enumerate().take(16) {
                eprint!("{result:<width$} ", result = result, width = 52);
                if i > 0 && (i % 2 == 1) {
                    eprint!("\n    ");
                }
            }

            eprint!("\n");
        }

        let path = Path::new(&dest_dir).join(format!("{}.json", &manifest.name));
        let mut output = Output{
            name: manifest.name.clone(),
            metadata: manifest.metadata.clone(),
            data: name,
            examples: examples,
        };

        eprintln!("Writing {}", path.clone().to_str().unwrap());

        serde_json::to_writer(File::create(path).expect("Opening output filed failed"), &output).expect("Writing output failed.");

        collection.items.push(CollectionItem{name: output.name.clone(), metadata: output.metadata.clone()});

        eprint!("\n\n");
    }

    let path = Path::new(&dest_dir).join("_collection.json");
    serde_json::to_writer(File::create(path).expect("Opening output filed failed"), &collection).expect("Writing collection failed.");
}