import { Component, ViewChild, ElementRef } from '@angular/core';
import { Logger } from '../core/logger';
import { Router } from '@angular/router';
import { 
  FormGroup,
  FormControl,
  Validators,
  FormBuilder,
  AbstractControl,
  ValidationErrors
} from '@angular/forms';
import { AccountService } from '../core/account.service';
import { OrgService } from '../core/org.service';
import { TransactionService } from '../core/transaction.service';
import { Account, AccountApi, AccountTree } from '../shared/account';
import { Transaction } from '../shared/transaction';
import { AppError } from '../shared/error';
import { Util } from '../shared/util';
import { NgbModal, ModalDismissReasons } from '@ng-bootstrap/ng-bootstrap';
import { ReconcileModal } from './reconcile-modal';
import { Reconciliation } from './reconciliation';
import { SessionService } from '../core/session.service';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/observable/from';
import 'rxjs/add/operator/mergeMap';

@Component({
  selector: 'app-reconcile',
  templateUrl: 'reconcile.html'
})
export class ReconcilePage {

  public accountForm: FormGroup;
  public newReconcile: FormGroup;
  public selectAccounts: any[];
  public account: Account;
  public pastReconciliations: Reconciliation[];
  public unreconciledTxs: Transaction[];
  public error: AppError;
  private accountTree: AccountTree;
  @ViewChild('confirmDeleteModal') confirmDeleteModal: ElementRef;

  constructor(
    private router: Router,
    private log: Logger,
    private accountService: AccountService,
    private orgService: OrgService,
    private txService: TransactionService,
    private fb: FormBuilder,
    private modalService: NgbModal,
    private sessionService: SessionService) {

    let org = this.orgService.getCurrentOrg();
    this.accountForm = fb.group({
      'accountId': [null, Validators.required]
    });

    this.newReconcile = fb.group({
      'startDate': ['', Validators.required],
      'startBalance': [{value: 0, disabled: true}, Validators.required],
      'endDate': ['', Validators.required],
      'endBalance': [0, Validators.required]
    });

    this.accountService.getAccountTree().subscribe(tree => {
      this.accountTree = tree;
      this.selectAccounts = tree.getFlattenedAccounts();
    });
  }

  onChooseAccount() {
    let account = this.accountTree.accountMap[this.accountForm.value.accountId];

    if(!account) {
      this.error = new AppError('Invalid account');
      return;
    }

    this.account = account;

    this.processTransactions();
  }

  startReconcile() {
    let value = this.newReconcile.getRawValue();

    let rec = new Reconciliation();
    rec.startDate = Util.getDateFromLocalDateString(value.startDate);
    rec.endDate = Util.getDateFromLocalDateString(value.endDate);
    rec.startBalance = Math.round(parseFloat(value.startBalance) * Math.pow(10, this.account.precision));
    rec.endBalance = Math.round(parseFloat(value.endBalance) * Math.pow(10, this.account.precision));

    this.log.debug(rec);

    let modal = this.modalService.open(ReconcileModal, {size: 'lg'});

    modal.componentInstance.setData(this.account, rec, this.unreconciledTxs);

    modal.result.then((txs) => {
      this.log.debug('reconcile modal save');
      rec.txs = txs;

      this.pastReconciliations.unshift(rec);

      this.newReconcile.patchValue(
        {
          startDate: Util.getLocalDateString(rec.endDate),
          startBalance: rec.endBalance / Math.pow(10, this.account.precision),
          endBalance: 0,
          endDate: ''
        }
      );
    }, (reason) => {
      this.log.debug('cancel reconcile modal');
    });
  }

  processTransactions() {
    // Get all transactions for account
    // Figure out reconciliations
    //    startDate is date of first transaction
    //    add up reconciled splits for given endDate to get endBalance
    // sort by most recent first
    // most recent endDate is used for startDate
    // most recent endBalance is used for startBalance
    // guess at next endDate

    this.unreconciledTxs = [];
    this.pastReconciliations = [];

    this.txService.getTransactionsByAccount(this.account.id).subscribe(txs => {
      let reconcileMap: {[date: number]: Reconciliation} = {};

      let firstStartDate: Date = null;
      let firstEndDate: Date = null;

      txs.forEach(tx => {
        if(!firstStartDate || (!firstEndDate && tx.date < firstStartDate)) {
          firstStartDate = tx.date;
        }

        let data = tx.getData();

        if(!data.reconciledSplits) {
          this.unreconciledTxs.push(tx);
          return;
        }

        let reconciled = true;
        let splitIndexes = Object.keys(data.reconciledSplits).map(index => parseInt(index));

        tx.splits.forEach((split, index) => {
          if(split.accountId !== this.account.id) {
            return;
          }

          if(splitIndexes.indexOf(index) === -1) {
            reconciled = false;
            return;
          }

          let endDate = new Date(data.reconciledSplits[index]);

          if(!firstEndDate || endDate < firstEndDate) {
            firstEndDate = endDate;
            firstStartDate = new Date(tx.date);
          }

          if(endDate.getTime() === firstEndDate.getTime() && tx.date < firstStartDate) {
            firstStartDate = new Date(tx.date);
          }

          if(!reconcileMap[endDate.getTime()]) {
            reconcileMap[endDate.getTime()] = new Reconciliation();
            reconcileMap[endDate.getTime()].endDate = endDate;
            reconcileMap[endDate.getTime()].net = 0;
          }

          let r = reconcileMap[endDate.getTime()];

          r.txs.push(tx);

          if(this.account.debitBalance) {
            r.net += split.amount;
          } else {
            r.net -= split.amount;
          }
        });

        if(!reconciled) {
          this.unreconciledTxs.push(tx);
        }
      });

      // Figure out starting date, beginning balance and ending balance
      let dates = Object.keys(reconcileMap).sort((a, b) => {
        return parseInt(a) - parseInt(b);
      }).map(time => {
        return new Date(parseInt(time));
      });

      if(!dates.length) {
        if(firstStartDate) {
          this.newReconcile.patchValue({startDate: Util.getLocalDateString(firstStartDate)});
        }
        return;
      }

      let firstRec = reconcileMap[dates[0].getTime()];
      firstRec.startDate = firstStartDate;
      firstRec.startBalance = 0;
      firstRec.endBalance = firstRec.net;

      this.pastReconciliations.unshift(firstRec);

      let lastRec = firstRec;

      for(let i = 1; i < dates.length; i++) {
        let rec = reconcileMap[dates[i].getTime()];
        rec.startDate = new Date(lastRec.endDate);
        rec.startBalance = lastRec.endBalance;
        rec.endBalance = rec.startBalance + rec.net;
        this.pastReconciliations.unshift(rec);
        lastRec = rec;
      }

      this.newReconcile.patchValue(
        {
          startDate: Util.getLocalDateString(lastRec.endDate),
          startBalance: lastRec.endBalance / Math.pow(10, this.account.precision)
        }
      );
    });
  }

  delete() {
    this.modalService.open(this.confirmDeleteModal).result.then((result) => {
      this.sessionService.setLoading(true);

      let rec = this.pastReconciliations[0];
  
      Observable.from(rec.txs).mergeMap(tx => {
        let oldId = tx.id;
        tx.id = Util.newGuid();

        let data = tx.getData();

        let newSplits = {};

        for(let splitId in data.reconciledSplits) {
          if(tx.splits[splitId].accountId !== this.account.id) {
            newSplits[splitId] = tx.splits[splitId];
          }
        }

        data.reconciledSplits = newSplits;

        tx.setData(data);
  
        return this.txService.putTransaction(oldId, tx);
      }, 8).subscribe(tx => {
        this.log.debug('Saved tx ' + tx.id);
      }, err => {
        this.error = err;
        this.sessionService.setLoading(false);
      }, () => {
        this.pastReconciliations.shift();
        let lastRec = this.pastReconciliations[0];

        if(lastRec) {
          this.newReconcile.patchValue(
            {
              startDate: Util.getLocalDateString(lastRec.endDate),
              startBalance: lastRec.endBalance / Math.pow(10, this.account.precision)
            }
          );
        } else {
          this.newReconcile.patchValue(
            {
              startDate: null,
              startBalance: 0
            }
          );
        }

        this.sessionService.setLoading(false);
      });
    }, (reason) => {
      this.log.debug('cancel delete');
    });
  }

}