#! /usr/bin/env runjs

var ByteArrayOutputStream = java.io.ByteArrayOutputStream;
var Bytes = Packages.me.hatter.tools.commons.bytes.Bytes;
var FileUtil = Packages.me.hatter.tools.commons.file.FileUtil;

var argsjs = require('component-args.js');

var CALIBRE_HOME = '/Applications/calibre.app/Contents/MacOS';

var DOT = 'dot';
var NPM = 'npm';
var GITBOOK = 'gitbook';
var CALIBRE_EBOOK_CONVERT = 'ebook-convert';

var NODE_INSTALL_URL = 'https://nodejs.org/en/download/';
var CALIBRE_INSTALL_URL = 'https://calibre-ebook.com/download';

var DOT_INSTALL = 'brew install graphviz';
var GITBOOK_INSTALL = 'npm install -g gitbook-cli';

var DEFAULT_PROCESSOR_VIZ = null;
var DEFAULT_PROCESSOR = {
    'plantuml': (lns, tmpDir) => {
        $ONCE('gitbook.js-defaultprocessor-plantuml-requirejar-plantuml').run(() => {
            requireJAR('plantuml-8059.jar');
        });
        var FileFormat = Packages.net.sourceforge.plantuml.FileFormat;
        var FileFormatOption = Packages.net.sourceforge.plantuml.FileFormatOption;
        var SourceStringReader = Packages.net.sourceforge.plantuml.SourceStringReader;

        var puml = $ARR(lns).join('\n');
        var dgst = Bytes.from(puml).digest($$.digests().sha256()).asHex();
        var baos = new ByteArrayOutputStream();
        var reader = new SourceStringReader(puml);
        reader.generateImage(baos, new FileFormatOption(FileFormat.PNG, false));
        $$.rFile(tmpDir, dgst + '.png').write(baos.toByteArray());
        return '<img src="' + dgst + '.png' + '">';
    },
    'graphviz': (lns, tmpDir) => {
        var viz = $ARR(lns).join('\n');
        var vizB64 = Bytes.from(viz).asBase64();
        var dgst = Bytes.from(viz).digest($$.digests().sha256()).asHex();
        var vizToPngRes = $$.shell().commands('sh', '-c', 'echo ' + vizB64 + ' | base64 -D | dot -Tpng').start();
        $$.rFile(tmpDir, dgst + '.png').write(vizToPngRes[0].bytes());
        return '<img src="' + dgst + '.png' + '">';
    }
};

// return null or string
var dealWithMarkdown = (f, tmpDir, mdList, plugins) => {
    var list = [];
    var codeTag = null;
    var codeList = [];
    var inCode = false;
    $ARR(mdList).forEach((ln) => {
        if (inCode) {
            if ($STR(ln.trim()) == '```') {
                // CODE ENDED
                inCode = false;
                var plugInFunc = null;
                plugins.forEach((p) => {
                    if (plugInFunc == null) {
                        plugInFunc = p[codeTag || 'default'];
                    }
                });
                if (plugInFunc == null) {
                    // plugin not found
                    list.push('```' + codeTag);
                    codeList.forEach((ln) => { list.push(ln) } );
                    list.push('```');
                } else {
                    list.push(plugInFunc(codeList, tmpDir));
                }
            } else {
                codeList.push(ln);
            }
        } else if (ln.trim().startsWith('```')) {
            // CODE STARTED
            inCode = true;
            codeList = [];
            codeTag = ln.trim().substring(3).trim();
        } else {
            list.push(ln);
        }
    });
    if (inCode) {
        xprintln('[ERROR] Markdown content error: ' + f);
        return null;
    }
    return list.join('\n');
};

// gitbook-cli OR https://github.com/GitbookIO/gitbook-pdf ?
var main = () => {
    var args = argsjs.parseDefARGs(['default-processor', 'skip-delete-tmp']);
    if (args.length < 1) {
        xprintln('[ERROR] Need arguments.');
        xprintln();
        xprintln('gitbook.js [args] <output.ext>');
        xprintln('      --default-processor            enable default processor');
        xprintln('      --skip-delete-tmp              skip delete tmp dir');
        xprintln('  -p, --processor <processor.js>     with file processor');
        xprintln('  -t, --type <"pdf">                 default pdf');
        xprintln('  -d, --dir <dir>                    default "."');
        return;
    }

    var whichRes = $$.shell().commands('which', NPM).start();
    if ($STR(whichRes[0].toString().trim()) == '') {
        xprintln('[ERROR] Node is not installed.');
        xprintln('[INFO] Install node URL: ' + NODE_INSTALL_URL);
        return;
    }
    xprintln('[OK] Check node installed: ' + $$.shell().commands('node', '-v').start()[0].toString().trim());
    var gitbookRes = $$.shell().commands('which', GITBOOK).start();
    if ($STR(gitbookRes[0].toString().trim()) == '') {
        xprintln('[ERROR] Gitbook is not installed.');
        xprintln('[INFO] Install gitbook command: ' + GITBOOK_INSTALL);
        return;
    }
    xprintln('[OK] Check gitbook installed: ' + $$.shell().commands('gitbook', '-V').start()[0].toString().trim().replace('\n', '; '));
    var dotRes = $$.shell().commands('which', DOT).start();
    if ($STR(dotRes[0].toString().trim()) == '') {
        xprintln('[ERROR] Graphviz is not installed.');
        xprintln('[INFO] Install graphviz command: ' + DOT_INSTALL);
        return;
    }
    xprintln('[OK] Check graphviz installed: ' + $$.shell().commands('dot', '-V').mergeErrorOutput(true).start()[0].toString().trim().replace('\n', '; '));
    var ebookConvert = $$.file(CALIBRE_HOME, CALIBRE_EBOOK_CONVERT);
    if (!(ebookConvert.exists())) {
        xprintln('[ERROR] Calibre is not installed.');
        xprintln('[INFO] Install calibre URL: ' + CALIBRE_INSTALL_URL);
        return;
    }
    xprintln('[OK] Check calibre installed: ' + $$.shell().commands(ebookConvert.getAbsolutePath(), '--version').start()[0].list().get(0));

    var gitbookShell = $$.shell();
    var ebookConvertRes = $$.shell().commands('which', CALIBRE_EBOOK_CONVERT).start();
    if ($STR(ebookConvertRes[0].toString().trim()) == '') {
        xprintln('[INFO] $PATH add calibre home: ' + CALIBRE_HOME);
        gitbookShell.env('PATH', '$PATH:' + CALIBRE_HOME);
    }

    var _type = args.val('t', 'type') || 'pdf';
    var _dir = args.val('d', 'dir') || '.';

    if ($STR(_type) != 'pdf') {
        xprintln('[ERROR] Currently only supports pdf.');
        return;
    }

    var _tempDir = $$.file(_dir, '.tmp');
    var plugins = [];
    var processors = args.vals('p', 'processor');
    processors.forEach((p) => {
        xprintln('[INFO] Load processor: ' + p);
        plugins.push(require('file://' + p));
    });
    if (args.flg('default-processor')) {
        plugins.push(DEFAULT_PROCESSOR);
    }
    if (plugins.length > 0) {
        if (_tempDir.exists()) {
            xprintln('[INFO] Delete exists tmp dir: ' + _tempDir);
            FileUtil.deleteDirectory(_tempDir);
        }
        xprintln('[INFO] Create tmp dir: ' + _tempDir);
        _tempDir.mkdirs();
        $ARR($$.file(_dir).listFiles()).forEach((f) => {
            if (f.getName().toLowerCase().endsWith('.md')) {
                var contents = $$.rFile(f).list();
                var newContents = dealWithMarkdown(f, _tempDir, contents, plugins);
                if (newContents != null) {
                    xprintln('[INFO] Update md file: ' + f.getName());
                    $$.rFile(_tempDir, f.getName()).write(newContents);
                } else {
                    $$.rFile(_tempDir, f.getName()).write(contents.join('\n'));
                }
            }
        });
    }

    var commands = [];
    commands.push(GITBOOK);
    commands.push(_type);
    commands.push((plugins.length > 0) ? _tempDir : _dir);
    commands.push(args[0]);

    xprintln('[INFO] Run gitbook command: ' + $TO_JAVA_LIST(commands));
    gitbookShell.commands(commands).run();

    if (_tempDir.exists()) {
        if (!(args.flg('skip-delete-tmp'))) {
            xprintln('[INFO] Delete tmp dir: ' + _tempDir);
            FileUtil.deleteDirectory(_tempDir);
        }
    }
};

main();