/**
 * @filedesc
 * Expands module path type to point to default export when no name is given
 */

const fs = require('fs');
const path = require('path');

let moduleRoot;

function addDefaultExportPath(obj) {
  if (!Array.isArray(obj)) {
    obj = obj.names;
  }
  obj.forEach((name, index) => {
    const matches = name.match(/module\:([^>|),\.<]|)+/g);
    if (matches) {
      matches.forEach(module => {
        if (!/[~\.]/.test(module)) {
          const checkFile = path.resolve(moduleRoot, module.replace(/^module\:/, ''));
          const file = fs.readFileSync(require.resolve(checkFile), 'utf-8');
          const lines = file.split('\n');
          let hasDefaultExport = false;
          for (let i = 0, ii = lines.length; i < ii; ++i) {
            hasDefaultExport = hasDefaultExport || /^export default [^\{]/.test(lines[i]);
            const match = lines[i].match(/^export default ([A-Za-z_$][A-Za-z0-9_$]+);$/);
            if (match) {
              // Use variable name if default export is assigned to a variable.
              obj[index] = name = name.replace(module, `${module}~${match[1]}`);
              return;
            }
          }
          if (hasDefaultExport) {
            // Duplicate last part if default export is not assigned to a variable.
            obj[index] = name = name.replace(module, `${module}~${module.split('/').pop()}`);
          }
        }
      });
    }
  });
}

function replaceLinks(comment) {
  const matches = comment.match(/\{@link [^\} #]+}/g);
  if (matches) {
    const modules = matches.map(m => {
      const mm = m.match(/(module:[^\}]+)}$/);
      if (mm) {
        return mm[1];
      }
    }).filter(m => !!m);
    const newModules = modules.concat();
    addDefaultExportPath(newModules);
    modules.forEach((module, i) => {
      comment = comment.replace(module, newModules[i]);
    });
  }
  return comment;
}

exports.handlers = {

  /**
   * Adds default export to module path types without name
   * @param {Object} e Event object.
   */
  newDoclet: function(e) {
    const doclet = e.doclet;
    if (doclet.kind == 'module') {
      const levelsUp = doclet.longname.replace(/^module\:/, '').split('/');
      if (doclet.meta.filename != 'index.js') {
        levelsUp.pop();
      }
      const pathArgs = [doclet.meta.path].concat(levelsUp.map(() => '../'));
      moduleRoot = path.resolve.apply(null, pathArgs);
    } else {
      if (doclet.description) {
        doclet.description = replaceLinks(doclet.description);
      }
      if (doclet.classdesc) {
        doclet.classdesc = replaceLinks(doclet.classdesc);
      }

      const module = doclet.longname.split('#').shift();
      if (module.indexOf('module:') == 0 && module.indexOf('.') !== -1) {
        doclet.longname = doclet.longname.replace(module, module.replace('.', '~'));
      }
      if (doclet.augments) {
        addDefaultExportPath(doclet.augments);
      }
      if (doclet.params) {
        doclet.params.forEach(p => addDefaultExportPath(p.type));
      }
      if (doclet.returns) {
        doclet.returns.forEach(r => addDefaultExportPath(r.type));
      }
      if (doclet.properties) {
        doclet.properties.forEach(p => addDefaultExportPath(p.type));
      }
      if (doclet.type) {
        addDefaultExportPath(doclet.type);
      }
    }
  }

};