let Classify = syzoj.model('classify');
let Problem = syzoj.model('problem');
let CToP = syzoj.model('classify_to_problem');
let Article = syzoj.model('article');
let User = syzoj.model('user');
let UToP = syzoj.model('user_to_practice');

app.get('/practice', async (req, res) => {
  if (!res.locals.user) {
    res.render('error', {
      err: new ErrorMessage('请先登录。')
    });
  } else {
    async function getUserInfo(userId) {
      let userQuery = await User.createQueryBuilder();
      const currentUserInfo = await userQuery.where("id = :id", { id: userId }).getOne();
      return currentUserInfo.current_p_id;
    }
    try {
      let classifyQuery = Classify.createQueryBuilder();
      let utopQuery = UToP.createQueryBuilder();
      let result = await Classify.queryAll(classifyQuery);
      let userQuery = await User.createQueryBuilder();
      const userId = res.locals.user.id;
      let currentPId = await getUserInfo(userId);
      const unFinishedIdArray = [];
      if (!currentPId) {
        // 用户第一次进入练习板块
        await userQuery.update(User).set({current_p_id: 1}).where("id = :id", { id:userId }).execute();
        currentPId = 1;
      } else {
        await result.forEachAsync(async resultItem => {
          const c_id = resultItem.id;
          let utopInfo = await utopQuery.where('c_id=:c_id',{c_id}).andWhere('u_id=:u_id',{u_id:userId}).andWhere("is_finished=1").getMany();
          resultItem.ac_num = utopInfo.length || 0;
          if (resultItem.ac_num === resultItem.problem_num) {
            if (resultItem.order < result.length ) {
              currentPId = resultItem.order + 1
              await userQuery.update(User).set({current_p_id: currentPId}).where("id = :id", { id:userId }).execute();
            }
          } else {
            unFinishedIdArray.push(resultItem.order);
          }
        });
      }
      if (unFinishedIdArray.length !== 0) {
        const minOrder = Math.min.apply(null,unFinishedIdArray);
        currentPId = minOrder;
        await userQuery.update(User).set({current_p_id: minOrder}).where("id = :id", { id:userId }).execute();
      }
      result.sort(function(a,b) {
        return a.order - b.order;
      });
      result.forEach(function(item) {
        if (item.order <= currentPId) {
          item.href = `/practice/classify/${item.id}`;
        }
        item.isNow = item.order === currentPId;
      });
      let userACArray = await utopQuery.where('u_id=:u_id',{u_id:userId}).andWhere("is_finished=1").getMany();
      if (syzoj.config.practice_rating) {
        const originRating = syzoj.config.default.user.rating;
        const newRating = originRating + userACArray.length * syzoj.config.practice_rating;
        await userQuery.update(User).set({rating: newRating}).where('id=:u_id',{u_id:userId}).execute();
      }
      res.render('practice', {
        user:res.locals.user,
        result
      })
    } catch (e) {
      syzoj.log(e);
      res.render('error', {
        err: e
      });
    }
  }
});

app.get('/practice/classify/:cid/problem/:pid', async (req, res) => {
  try {
    let id = parseInt(req.params.pid);
    let cid = parseInt(req.params.cid);
    let problem = await Problem.findById(id);
    if (!problem) throw new ErrorMessage('无此题目。');
    
    if (!await problem.isAllowedUseBy(res.locals.user)) {
      throw new ErrorMessage('您没有权限进行此操作。');
    }
    
    problem.allowedEdit = await problem.isAllowedEditBy(res.locals.user);
    problem.allowedManage = await problem.isAllowedManageBy(res.locals.user);
    
    if (problem.is_public || problem.allowedEdit) {
      await syzoj.utils.markdown(problem, ['description', 'input_format', 'output_format', 'example', 'limit_and_hint']);
    } else {
      throw new ErrorMessage('您没有权限进行此操作。');
    }
    
    let state = await problem.getJudgeState(res.locals.user, false);
    
    problem.tags = await problem.getTags();
    await problem.loadRelationships();
    
    let testcases = await syzoj.utils.parseTestdata(problem.getTestdataPath(), problem.type === 'submit-answer');
    
    let discussionCount = await Article.count({ problem_id: id });
    
    res.render('practice_problem', {
      problem: problem,
      state: state,
      lastLanguage: res.locals.user ? await res.locals.user.getLastSubmitLanguage() : null,
      testcases: testcases,
      discussionCount: discussionCount,
      pid: id,
      cid
    });
  } catch (e) {
    syzoj.log(e);
    res.render('error', {
      err: e
    });
  }
});

app.get('/practice/classify/:id', async (req, res) => {
  try {
    const c_id = parseInt(req.params.id);
    const u_id = res.locals.user.id;
    let ctopQuery = CToP.createQueryBuilder();
    let query = await Problem.createQueryBuilder();
    let utopQuery = UToP.createQueryBuilder();
    let problemArray = await ctopQuery.where("c_id = :id", { id:c_id }).getMany();
    let utopResult = await utopQuery.where("c_id = :c_id", { c_id }).andWhere("u_id=:u_id", {u_id}).getMany();
    let problems = await problemArray.mapAsync(async problemArrayInfo => query.where('id=:id', {id: problemArrayInfo.p_id}).getOne());
    problems.forEach(function(problemItem) {
      const obj = utopResult.find(function(item){return parseInt(item.p_id) === parseInt(problemItem.id)});
      problemItem.href = `/practice/classify/${c_id}/problem/${problemItem.id}`;
      if (obj) {
        problemItem.statusStr = obj.is_practice && obj.is_finished ? '已练习且已通过' : '已练习但未通过';
      } else {
        problemItem.statusStr = '尚未练习'
      }
    });
    problems.sort(function(a, b){
      return a.id - b.id;
    })
    res.render('practice_classify', {
      user:res.locals.user,
      problems
    })
  } catch (e) {
    syzoj.log(e);
    res.render('error', {
      err: e
    });
  }
});

app.get('/api/practice/classify/:id', async (req, res) => {
  try {
    let id = parseInt(req.params.id);
    let query = await Classify.createQueryBuilder();
    let classifyInfo = await query.where('id=:id',{id}).getOne();
    let problem = await CToP.queryBy({c_id: id});
    res.send({ classifyInfo, problem:problem.map(function(item){return item.p_id}) });
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '失败' });
  }
});

app.get('/api/pass/:cid/:pid',async (req, res) => {
  try {
    const c_id = parseInt(req.params.cid);
    const p_id = parseInt(req.params.pid);
    const u_id = res.locals.user.id;
    let utopQuery = UToP.createQueryBuilder();
    let query = Classify.createQueryBuilder();
    let userQuery = User.createQueryBuilder();
    let classify = await Classify.queryAll(query);
    classify.sort(function(a,b) {
      return a.order - b.order;
    });
    let utopResult = await utopQuery.where("c_id = :c_id", { c_id }).andWhere("u_id=:u_id", {u_id}).andWhere("p_id=:p_id", {p_id}).getOne();
    // 查询到结果了
    if (utopResult ) {
      // mock答题通过了
      await utopQuery.update(UToP).set({is_finished: 1, practice_num: utopResult.practice_num + 1}).where("c_id = :c_id", { c_id }).andWhere("u_id=:u_id", {u_id}).andWhere("p_id=:p_id", {p_id}).execute();
      // 说明两个题都练习过了
    } else {
      let utop = await UToP.create({
        u_id,
        c_id,
        p_id,
        is_practice: 1,
        is_finished: 1,
        practice_num: 1
      });
      await utop.save();
    }
    res.send();
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '练习失败，请稍后重试' });
  }
});

app.get('/api/nopass/:cid/:pid',async (req, res) => {
  try {
    const c_id = parseInt(req.params.cid);
    const p_id = parseInt(req.params.pid);
    const u_id = res.locals.user.id;
    let utopQuery = UToP.createQueryBuilder();
    let query = Classify.createQueryBuilder();
    let utopResult = await utopQuery.where("c_id = :c_id", { c_id }).andWhere("u_id=:u_id", {u_id}).andWhere("p_id=:p_id", {p_id}).getOne();
    // 查询到结果了
    if (utopResult) {
      // mock答题通过了
      await utopQuery.update(UToP).set({is_practice:1, is_finished: 0, practice_num: utopResult.practice_num + 1}).where("c_id = :c_id", { c_id }).andWhere("u_id=:u_id", {u_id}).andWhere("p_id=:p_id", {p_id}).execute();
      // 说明两个题都练习过了
    } else {
      let utop = await UToP.create({
        u_id,
        c_id,
        p_id,
        is_practice: 1,
        practice_num: 1,
        is_finished: 0
      });
      await utop.save();
    }
    res.send();
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '练习失败，请稍后重试' });
  }
});

app.put('/api/practice/classify/update/:id', async (req, res) => {
  try {
    let id = parseInt(req.params.id);
    let u_id = parseInt(res.locals.user.id);
    let utopQuery = UToP.createQueryBuilder();
    let classifyQuery = await Classify.createQueryBuilder();
    let ctopQuery = await CToP.createQueryBuilder();
    const {name, intro, problemIdArray, order} = req.body;
    let classifyInfo = await classifyQuery.where('id=:id',{id}).getOne();
    // 新增题
    if (problemIdArray.length > classifyInfo.problem_num) {
      /*
      * 把当前练习的阶段设置为新增题的阶段，因为新增题后，当前阶段的题目就没答完。
      * */
      
    }
    // 删除题
    if (problemIdArray.length < classifyInfo.problem_num) {
      // 1。找出两个数组的差异
      function findDifference(source, target){
        const parseIntTarget = target.map(function(item){
          return parseInt(item);
        })
        return source.filter(function(item){
          return !parseIntTarget.includes(item);
        })
      }
      let ctopInfo = await ctopQuery.where('c_id=:id',{id}).getMany();
      const targetArray = ctopInfo.map(function(ctopInfoItem){
        return ctopInfoItem.p_id;
      })
      // 2.从utop表里清除被删除题目的练习记录
      const differenceArray = findDifference(targetArray, problemIdArray);
      differenceArray.forEachAsync(async differenceItem => {
        await utopQuery.delete().from(UToP).where("c_id = :id", { id }).andWhere("u_id=:u_id",{u_id}).andWhere("p_id=:p_id",{p_id:differenceItem}).execute();
      })
    }
    let updateClassifyInfo = await classifyQuery.update(Classify).set({name, intro, order, problem_num: problemIdArray.length}).where("id = :id", { id }).execute();
    await ctopQuery.delete().from(CToP).where("c_id = :id", { id }).execute();
    problemIdArray.forEach(async function (item) {
      let ctop = await CToP.create({
        c_id: id,
        p_id: item
      });
      await ctop.save();
    })
    res.send({ updateClassifyInfo });
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '失败' });
  }
});

app.get('/api/pagination/allproblem', async (req, res) => {
  try {
    let query = await Problem.createQueryBuilder();
    let problemInfo = await query.select('COUNT(*)', 'count').getRawOne();
    res.send({ problemInfo});
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '失败' });
  }
});

app.get('/api/pagination', async (req, res) => {
  let pagesize = parseInt(req.query.pagesize);
  let page = parseInt(req.query.page);
  try {
    let query = await Problem.createQueryBuilder();
    let problemInfo = await query.limit(pagesize).offset(pagesize*page).getMany();
    res.send({ problemInfo});
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '失败' });
  }
});

app.get('/api/getProblem/:id', async (req, res) => {
  let id = parseInt(req.params.id);
  try {
    let query = await Problem.createQueryBuilder();
    let problemInfo = await query.where('id=:id', {id}).getOne()
    res.send({ problemInfo});
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '失败' });
  }
});

app.get('/api/practice/all', async (req, res) => {
  try {
    let classifyQuery = Classify.createQueryBuilder();
    let ctopQuery = CToP.createQueryBuilder();
    let result = await Classify.queryAll(classifyQuery);
    result.sort(function(a,b) {
      return a.order - b.order;
    })
    let problem = await CToP.queryAll(ctopQuery);
    res.send({ result, problem});
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '失败' });
  }
});

app.get('/api/admin/practice/all', async (req, res) => {
  try {
    let classifyQuery = Classify.createQueryBuilder();
    let result = await Classify.queryAll(classifyQuery);
    res.send({ result });
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '失败' });
  }
});

app.post('/api/practice/create', async (req, res) => {
  try {
    const {name, intro, problemIdArray, order} = req.body;
    let classify = await Classify.create({
      name,
      intro,
      order,
      problem_num: problemIdArray.length || 0,
      updateTime: parseInt((new Date()).getTime() / 1000, 10),
      createTime: parseInt((new Date()).getTime() / 1000)
    });
    await classify.save();
    let query = Classify.createQueryBuilder();
    let recordArray =  await Classify.queryAll(query);
    let lastRecordId = recordArray[recordArray.length - 1].id;
    problemIdArray.forEach(async function (item) {
      let ctop = await CToP.create({
        c_id: lastRecordId,
        p_id: item
      })
      await ctop.save();
    })
    res.send();
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '创建失败' });
  }
});

app.get('/api/problem/all', async (req, res) => {
  try {
    let query = Problem.createQueryBuilder();
    let result = await Problem.querySomeColumn(query);
    res.send({ result });
  } catch(e) {
    res.send({ error_code: e.errno, error_msg: '失败' });
  }
});