Support problem details in the source file.

Signed-off-by: Eric Wang <skygragon@gmail.com>

Author: skygragon

lib/commands/show.js

@@ -25,6 +25,12 @@ var cmd = {
       type:     'string',
       default:  config.LANG,
       describe: 'Program language to use'
+    },
+    extra: {
+      alias:    'x',
+      type:     'boolean',
+      default:  false,
+      describe: 'Provide extra problem details in generated file'
     }
   }
 };
@@ -41,10 +47,11 @@ cmd.handler = function(argv) {
       if (!template)
         return log.fail('Failed to generate source file, ' +
             'unknown language "' + argv.lang + '"');
+      problem.code = template.defaultCode;
 
-      var f = problem.key + h.langToExt(argv.lang);
-      fs.writeFileSync(f, template.defaultCode);
-      msg = sprintf('(File: %s)', chalk.yellow.underline(f));
+      var filename = problem.key + h.langToExt(argv.lang);
+      core.exportProblem(problem, filename, !argv.extra);
+      msg = sprintf('(File: %s)', chalk.yellow.underline(filename));
     }
 
     log.info(sprintf('[%d] %s %s\t%s\n',

lib/commands/submission.js

@@ -24,11 +24,17 @@ var cmd = {
       type:     'string',
       describe: 'Where to save the submissions',
       default:  '.'
+    },
+    extra: {
+      alias:    'x',
+      type:     'boolean',
+      default:  false,
+      describe: 'Provide extra problem details in submission file'
     }
   }
 };
 
-function getSubmissionDone(e, msg, problem, cb) {
+function onTaskDone(e, msg, problem, cb) {
   // NOTE: msg color means different purpose:
   // - red: error
   // - green: accepted, fresh download
@@ -42,12 +48,25 @@ function getSubmissionDone(e, msg, problem, cb) {
   if (cb) cb(e);
 }
 
-function getSubmission(argv, problem, cb) {
-  var done = _.partial(getSubmissionDone, _, _, problem, cb);
+function onTaskRun(argv, problem, cb) {
+  var done = _.partial(onTaskDone, _, _, problem, cb);
+
+  if (argv.extra) {
+    // have to get problem details, e.g. problem description.
+    core.getProblem(problem.id, function(e, problem) {
+      if (e) return done(e);
+
+      exportSubmission(argv, problem, done);
+    });
+  } else {
+    exportSubmission(argv, problem, done);
+  }
+}
 
+function exportSubmission(argv, problem, cb) {
   core.getSubmissions(problem, function(e, submissions) {
-    if (e) return done(e);
-    if (submissions.length === 0) return done('no submissions?');
+    if (e) return cb(e);
+    if (submissions.length === 0) return cb('no submissions?');
 
     // find the latest accepted one
     var submission = _.find(submissions, function(x) {
@@ -67,24 +86,25 @@ function getSubmission(argv, problem, cb) {
 
     // skip the existing cached submissions
     if (fs.existsSync(filename)) {
-      return done(null, chalk.underline(filename));
+      return cb(null, chalk.underline(filename));
     }
 
     core.getSubmission(submission, function(e, submission) {
-      if (e) return done(e);
+      if (e) return cb(e);
 
-      fs.writeFileSync(filename, submission.code);
+      problem.code = submission.code;
+      core.exportProblem(problem, filename, !argv.extra);
 
       if (submission.state === 'Accepted')
-        done(null, chalk.green.underline(filename));
+        cb(null, chalk.green.underline(filename));
       else
-        done(null, chalk.yellow.underline(filename));
+        cb(null, chalk.yellow.underline(filename));
     });
   });
 }
 
 cmd.handler = function(argv) {
-  var doTask = _.partial(getSubmission, argv, _, _);
+  var doTask = _.partial(onTaskRun, argv, _, _);
 
   if (argv.all) {
     core.getProblems(function(e, problems) {

lib/core.js

@@ -1,9 +1,14 @@
+var fs = require('fs');
+var path = require('path');
+var util = require('util');
+
 var _ = require('underscore');
 var log = require('loglevel');
 
 var cache = require('./cache');
 var config = require('./config');
 var client = require('./leetcode_client');
+var h = require('./helper');
 
 var core = {};
 
@@ -91,6 +96,32 @@ core.starProblem = function(problem, starred, cb) {
   client.starProblem(problem, starred, cb);
 };
 
+core.exportProblem = function(problem, f, codeOnly) {
+  var output = '';
+
+  if (codeOnly) {
+    output = problem.code;
+  } else {
+    var input = h.langToCommentStyle(h.extToLang(f));
+    // copy problem attrs thus we can render it in template
+    _.extend(input, problem);
+    input.percent = input.percent.toFixed(2);
+    input.testcase = util.inspect(input.testcase || '');
+
+    // NOTE: wordwrap internally uses '\n' as EOL, so here we have to
+    // remove all '\r' in the raw string.
+    // FIXME: while in template file we still use '\r\n' for the sake
+    // of windows, is it really necessary?
+    var wrap = require('wordwrap')(79 - input.commentLine.length);
+    input.desc = wrap(input.desc.replace(/\r\n/g, '\n')).split('\n');
+
+    var tpl = fs.readFileSync(path.resolve(__dirname, '../source.tpl'), 'utf-8');
+    output = _.template(tpl)(input);
+  }
+
+  fs.writeFileSync(f, output);
+};
+
 core.login = function(user, cb) {
   var self = this;
   client.login(user, function(e, user) {

lib/helper.js

@@ -75,6 +75,31 @@ h.extToLang = function(fullpath) {
   }
 };
 
+h.langToCommentStyle = function(lang) {
+  switch (lang) {
+    case 'c':
+    case 'cpp':
+    case 'csharp':
+    case 'golang':
+    case 'java':
+    case 'javascript':
+    case 'swift':
+    default:
+      return {
+        commentHeader: '/*',
+        commentLine:   ' *',
+        commentFooter: ' */'
+      };
+    case 'python':
+    case 'ruby':
+      return {
+        commentHeader: '#',
+        commentLine:   '#',
+        commentFooter: '#'
+      };
+  }
+};
+
 h.getFileData = function(path) {
   return fs.existsSync(path) ? fs.readFileSync(path).toString() : null;
 };

package.json

@@ -46,6 +46,7 @@
     "mocha": "^3.0.2",
     "nock": "^8.0.0",
     "nyc": "^8.1.0",
-    "rewire": "^2.5.2"
+    "rewire": "^2.5.2",
+    "wordwrap": "^1.0.0"
   }
 }

source.tpl

@@ -0,0 +1,13 @@
+<%= commentHeader %>
+<%= commentLine %> [<%= id %>] <%= name %>
+<%= commentLine %>
+<%= commentLine %> <%= link %>
+<%= commentLine %>
+<%= commentLine %> <%= level %> (<%= percent %>%)
+<%= commentLine %> Total Accepted:    <%= totalAC %>
+<%= commentLine %> Total Submissions: <%= totalSubmit %>
+<%= commentLine %> Testcase Example:  <%= testcase %>
+<%= commentLine %>
+<% _.each(desc, function(x) { %><%= commentLine %> <%= x %>
+<% }) %><%= commentFooter %>
+<%= code %>