<?php
/**
 * BudgetController.php
 * Copyright (c) 2019 james@firefly-iii.org
 *
 * This file is part of Firefly III (https://github.com/firefly-iii).
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
declare(strict_types=1);

namespace FireflyIII\Http\Controllers\Report;

use Carbon\Carbon;
use FireflyIII\Http\Controllers\Controller;
use FireflyIII\Models\Account;
use FireflyIII\Models\Budget;
use FireflyIII\Repositories\Budget\BudgetLimitRepositoryInterface;
use FireflyIII\Repositories\Budget\BudgetRepositoryInterface;
use FireflyIII\Repositories\Budget\NoBudgetRepositoryInterface;
use FireflyIII\Repositories\Budget\OperationsRepositoryInterface;
use FireflyIII\Support\CacheProperties;
use FireflyIII\Support\Http\Controllers\BasicDataSupport;
use FireflyIII\Support\Report\Budget\BudgetReportGenerator;
use Illuminate\Contracts\View\Factory;
use Illuminate\Support\Collection;
use Illuminate\View\View;
use JsonException;
use Log;
use Throwable;

/**
 * Class BudgetController.
 */
class BudgetController extends Controller
{
    use BasicDataSupport;

    private BudgetLimitRepositoryInterface $blRepository;
    private NoBudgetRepositoryInterface    $nbRepository;
    private OperationsRepositoryInterface  $opsRepository;
    private BudgetRepositoryInterface      $repository;

    /**
     * ExpenseReportController constructor.
     *
     * @codeCoverageIgnore
     */
    public function __construct()
    {
        parent::__construct();
        $this->middleware(
            function ($request, $next) {
                $this->opsRepository = app(OperationsRepositoryInterface::class);
                $this->repository    = app(BudgetRepositoryInterface::class);
                $this->blRepository  = app(BudgetLimitRepositoryInterface::class);
                $this->nbRepository  = app(NoBudgetRepositoryInterface::class);

                return $next($request);
            }
        );
    }

    /**
     * Partial used in the budget report.
     *
     * @param Collection $accounts
     * @param Collection $budgets
     * @param Carbon     $start
     * @param Carbon     $end
     *
     * @return Factory|View
     */
    public function accountPerBudget(Collection $accounts, Collection $budgets, Carbon $start, Carbon $end)
    {
        /** @var BudgetReportGenerator $generator */
        $generator = app(BudgetReportGenerator::class);

        $generator->setUser(auth()->user());
        $generator->setAccounts($accounts);
        $generator->setBudgets($budgets);
        $generator->setStart($start);
        $generator->setEnd($end);

        $generator->accountPerBudget();
        $report = $generator->getReport();

        return prefixView('reports.budget.partials.account-per-budget', compact('report', 'budgets'));
    }

    /**
     * @param Collection $accounts
     * @param Collection $budgets
     * @param Carbon     $start
     * @param Carbon     $end
     *
     * @return Factory|View
     */
    public function accounts(Collection $accounts, Collection $budgets, Carbon $start, Carbon $end)
    {
        $spent  = $this->opsRepository->listExpenses($start, $end, $accounts, $budgets);
        $report = [];
        $sums   = [];
        /** @var Account $account */
        foreach ($accounts as $account) {
            $accountId          = $account->id;
            $report[$accountId] = $report[$accountId] ?? [
                    'name'       => $account->name,
                    'id'         => $account->id,
                    'iban'       => $account->iban,
                    'currencies' => [],
                ];
        }

        // loop expenses.
        foreach ($spent as $currency) {
            $currencyId        = $currency['currency_id'];
            $sums[$currencyId] = $sums[$currencyId] ?? [
                    'currency_id'             => $currency['currency_id'],
                    'currency_symbol'         => $currency['currency_symbol'],
                    'currency_name'           => $currency['currency_name'],
                    'currency_decimal_places' => $currency['currency_decimal_places'],
                    'sum'                     => '0',
                ];
            foreach ($currency['budgets'] as $budget) {
                foreach ($budget['transaction_journals'] as $journal) {
                    $sourceAccountId                                            = $journal['source_account_id'];
                    $report[$sourceAccountId]['currencies'][$currencyId]        = $report[$sourceAccountId]['currencies'][$currencyId] ?? [
                            'currency_id'             => $currency['currency_id'],
                            'currency_symbol'         => $currency['currency_symbol'],
                            'currency_name'           => $currency['currency_name'],
                            'currency_decimal_places' => $currency['currency_decimal_places'],
                            'sum'                     => '0',
                        ];
                    $report[$sourceAccountId]['currencies'][$currencyId]['sum'] = bcadd(
                        $report[$sourceAccountId]['currencies'][$currencyId]['sum'],
                        $journal['amount']
                    );
                    $sums[$currencyId]['sum']                                   = bcadd($sums[$currencyId]['sum'], $journal['amount']);
                }
            }
        }

        return prefixView('reports.budget.partials.accounts', compact('sums', 'report'));
    }

    /**
     * @param Collection $accounts
     * @param Collection $budgets
     * @param Carbon     $start
     * @param Carbon     $end
     *
     * @return string
     */
    public function avgExpenses(Collection $accounts, Collection $budgets, Carbon $start, Carbon $end)
    {
        $spent  = $this->opsRepository->listExpenses($start, $end, $accounts, $budgets);
        $result = [];
        foreach ($spent as $currency) {
            foreach ($currency['budgets'] as $budget) {
                foreach ($budget['transaction_journals'] as $journal) {
                    $destinationId = $journal['destination_account_id'];
                    $key           = sprintf('%d-%d', $destinationId, $currency['currency_id']);
                    $result[$key]  = $result[$key] ?? [
                            'transactions'             => 0,
                            'sum'                      => '0',
                            'avg'                      => '0',
                            'avg_float'                => 0,
                            'destination_account_name' => $journal['destination_account_name'],
                            'destination_account_id'   => $journal['destination_account_id'],
                            'currency_id'              => $currency['currency_id'],
                            'currency_name'            => $currency['currency_name'],
                            'currency_symbol'          => $currency['currency_symbol'],
                            'currency_decimal_places'  => $currency['currency_decimal_places'],
                        ];
                    $result[$key]['transactions']++;
                    $result[$key]['sum']       = bcadd($journal['amount'], $result[$key]['sum']);
                    $result[$key]['avg']       = bcdiv($result[$key]['sum'], (string)$result[$key]['transactions']);
                    $result[$key]['avg_float'] = (float)$result[$key]['avg'];
                }
            }
        }
        // sort by amount_float
        // sort temp array by amount.
        $amounts = array_column($result, 'avg_float');
        array_multisort($amounts, SORT_ASC, $result);

        try {
            $result = prefixView('reports.budget.partials.avg-expenses', compact('result'))->render();

        } catch (Throwable $e) { // @phpstan-ignore-line
            Log::debug(sprintf('Could not render reports.partials.budget-period: %s', $e->getMessage()));
            $result = sprintf('Could not render view: %s', $e->getMessage());
        }

        return $result;
    }

    /**
     * @param Collection $accounts
     * @param Collection $budgets
     * @param Carbon     $start
     * @param Carbon     $end
     *
     * @return Factory|View
     */
    public function budgets(Collection $accounts, Collection $budgets, Carbon $start, Carbon $end)
    {
        $spent  = $this->opsRepository->listExpenses($start, $end, $accounts, $budgets);
        $sums   = [];
        $report = [];
        /** @var Budget $budget */
        foreach ($budgets as $budget) {
            $budgetId          = $budget->id;
            $report[$budgetId] = $report[$budgetId] ?? [
                    'name'       => $budget->name,
                    'id'         => $budget->id,
                    'currencies' => [],
                ];
        }
        foreach ($spent as $currency) {
            $currencyId        = $currency['currency_id'];
            $sums[$currencyId] = $sums[$currencyId] ?? [
                    'currency_id'             => $currency['currency_id'],
                    'currency_symbol'         => $currency['currency_symbol'],
                    'currency_name'           => $currency['currency_name'],
                    'currency_decimal_places' => $currency['currency_decimal_places'],
                    'sum'                     => '0',
                ];
            /** @var array $budget */
            foreach ($currency['budgets'] as $budget) {
                $budgetId = $budget['id'];

                foreach ($budget['transaction_journals'] as $journal) {
                    // add currency info to report array:
                    $report[$budgetId]['currencies'][$currencyId]        = $report[$budgetId]['currencies'][$currencyId] ?? [
                            'sum'                     => '0',
                            'sum_pct'                 => '0',
                            'currency_id'             => $currency['currency_id'],
                            'currency_symbol'         => $currency['currency_symbol'],
                            'currency_name'           => $currency['currency_name'],
                            'currency_decimal_places' => $currency['currency_decimal_places'],

                        ];
                    $report[$budgetId]['currencies'][$currencyId]['sum'] = bcadd($report[$budgetId]['currencies'][$currencyId]['sum'], $journal['amount']);
                    $sums[$currencyId]['sum']                            = bcadd($sums[$currencyId]['sum'], $journal['amount']);
                }
            }
        }

        // loop again to get percentages.
        foreach ($report as $budgetId => $data) {
            foreach ($data['currencies'] as $currencyId => $dataX) {
                $sum   = $dataX['sum'] ?? '0';
                $total = $sums[$currencyId]['sum'] ?? '0';
                $pct   = '0';
                if (0 !== bccomp($sum, '0') && 0 !== bccomp($total, '9')) {
                    $pct = round((float)bcmul(bcdiv($sum, $total), '100'));
                }
                $report[$budgetId]['currencies'][$currencyId]['sum_pct'] = $pct;
            }
        }

        return prefixView('reports.budget.partials.budgets', compact('sums', 'report'));
    }

    /**
     * Show partial overview of budgets.
     *
     * @param Collection $accounts
     * @param Carbon     $start
     * @param Carbon     $end
     *
     * @return string
     */
    public function general(Collection $accounts, Carbon $start, Carbon $end)
    {
        /** @var BudgetReportGenerator $generator */
        $generator = app(BudgetReportGenerator::class);

        $generator->setUser(auth()->user());
        $generator->setAccounts($accounts);
        $generator->setStart($start);
        $generator->setEnd($end);

        $generator->general();
        $report = $generator->getReport();

        return prefixView('reports.partials.budgets', compact('report'))->render();
    }

    /**
     * Show budget overview for a period.
     *
     * @param Collection $accounts
     * @param Carbon     $start
     * @param Carbon     $end
     *
     * @return mixed|string
     * @throws JsonException
     */
    public function period(Collection $accounts, Carbon $start, Carbon $end)
    {
        $cache = new CacheProperties;
        $cache->addProperty($start);
        $cache->addProperty($end);
        $cache->addProperty('budget-period-report');
        $cache->addProperty($accounts->pluck('id')->toArray());
        if ($cache->has()) {
            return $cache->get();
        }

        $periods   = app('navigation')->listOfPeriods($start, $end);
        $keyFormat = app('navigation')->preferredCarbonFormat($start, $end);
        // list expenses for budgets in account(s)
        $expenses = $this->opsRepository->listExpenses($start, $end, $accounts);

        $report = [];
        foreach ($expenses as $currency) {
            foreach ($currency['budgets'] as $budget) {
                $count = 0;
                foreach ($budget['transaction_journals'] as $journal) {
                    $count++;
                    $key                               = sprintf('%d-%d', $budget['id'], $currency['currency_id']);
                    $dateKey                           = $journal['date']->format($keyFormat);
                    $report[$key]                      = $report[$key] ?? [
                            'id'                      => $budget['id'],
                            'name'                    => sprintf('%s (%s)', $budget['name'], $currency['currency_name']),
                            'sum'                     => '0',
                            'currency_id'             => $currency['currency_id'],
                            'currency_name'           => $currency['currency_name'],
                            'currency_symbol'         => $currency['currency_symbol'],
                            'currency_code'           => $currency['currency_code'],
                            'currency_decimal_places' => $currency['currency_decimal_places'],
                            'entries'                 => [],
                        ];
                    $report[$key]['entries'][$dateKey] = $report[$key] ['entries'][$dateKey] ?? '0';
                    $report[$key]['entries'][$dateKey] = bcadd($journal['amount'], $report[$key] ['entries'][$dateKey]);
                    $report[$key]['sum']               = bcadd($report[$key] ['sum'], $journal['amount']);
                    $report[$key]['avg']               = bcdiv($report[$key]['sum'], (string)count($periods));
                }
            }
        }
        try {
            $result = prefixView('reports.partials.budget-period', compact('report', 'periods'))->render();

        } catch (Throwable $e) { // @phpstan-ignore-line
            Log::debug(sprintf('Could not render reports.partials.budget-period: %s', $e->getMessage()));
            $result = 'Could not render view.';
        }

        $cache->store($result);

        return $result;
    }

    /**
     * @param Collection $accounts
     * @param Collection $budgets
     * @param Carbon     $start
     * @param Carbon     $end
     *
     * @return string
     */
    public function topExpenses(Collection $accounts, Collection $budgets, Carbon $start, Carbon $end)
    {
        $spent  = $this->opsRepository->listExpenses($start, $end, $accounts, $budgets);
        $result = [];
        foreach ($spent as $currency) {
            foreach ($currency['budgets'] as $budget) {
                foreach ($budget['transaction_journals'] as $journal) {
                    $result[] = [
                        'description'              => $journal['description'],
                        'transaction_group_id'     => $journal['transaction_group_id'],
                        'amount_float'             => (float)$journal['amount'],
                        'amount'                   => $journal['amount'],
                        'date'                     => $journal['date']->formatLocalized($this->monthAndDayFormat),
                        'date_sort'                => $journal['date']->format('Y-m-d'),
                        'destination_account_name' => $journal['destination_account_name'],
                        'destination_account_id'   => $journal['destination_account_id'],
                        'currency_id'              => $currency['currency_id'],
                        'currency_name'            => $currency['currency_name'],
                        'currency_symbol'          => $currency['currency_symbol'],
                        'currency_decimal_places'  => $currency['currency_decimal_places'],
                        'budget_id'                => $budget['id'],
                        'budget_name'              => $budget['name'],
                    ];
                }
            }
        }
        // sort by amount_float
        // sort temp array by amount.
        $amounts = array_column($result, 'amount_float');
        array_multisort($amounts, SORT_ASC, $result);

        try {
            $result = prefixView('reports.budget.partials.top-expenses', compact('result'))->render();

        } catch (Throwable $e) { // @phpstan-ignore-line
            Log::debug(sprintf('Could not render reports.partials.budget-period: %s', $e->getMessage()));
            $result = sprintf('Could not render view: %s', $e->getMessage());
        }

        return $result;
    }
}