<?php
/**
 * BudgetController.php
 * Copyright (c) 2017 thegrumpydictator@gmail.com
 *
 * This file is part of Firefly III.
 *
 * Firefly III is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Firefly III 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Firefly III. If not, see <http://www.gnu.org/licenses/>.
 */
declare(strict_types=1);

namespace FireflyIII\Http\Controllers\Chart;

use Carbon\Carbon;
use FireflyIII\Exceptions\FireflyException;
use FireflyIII\Generator\Chart\Basic\GeneratorInterface;
use FireflyIII\Helpers\Collector\GroupCollectorInterface;
use FireflyIII\Http\Controllers\Controller;
use FireflyIII\Models\Budget;
use FireflyIII\Models\BudgetLimit;
use FireflyIII\Models\TransactionType;
use FireflyIII\Repositories\Budget\BudgetRepositoryInterface;
use FireflyIII\Support\CacheProperties;
use FireflyIII\Support\Http\Controllers\AugumentData;
use FireflyIII\Support\Http\Controllers\DateCalculation;
use Illuminate\Http\JsonResponse;
use Illuminate\Support\Collection;

/**
 * Class BudgetController.
 *
 * @SuppressWarnings(PHPMD.ExcessiveClassComplexity)
 * @SuppressWarnings(PHPMD.CouplingBetweenObjects)
 *
 */
class BudgetController extends Controller
{
    use DateCalculation, AugumentData;
    /** @var GeneratorInterface Chart generation methods. */
    protected $generator;

    /** @var BudgetRepositoryInterface The budget repository */
    protected $repository;

    /**
     * BudgetController constructor.
     */
    public function __construct()
    {
        parent::__construct();

        $this->middleware(
            function ($request, $next) {
                $this->generator  = app(GeneratorInterface::class);
                $this->repository = app(BudgetRepositoryInterface::class);

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


    /**
     * Shows overview of a single budget.
     *
     * TODO this chart is not multi-currency aware.
     *
     * @param Budget $budget
     *
     * @return JsonResponse
     */
    public function budget(Budget $budget): JsonResponse
    {
        /** @var Carbon $start */
        $start = $this->repository->firstUseDate($budget) ?? session('start', new Carbon);
        /** @var Carbon $end */
        $end   = session('end', new Carbon);
        $cache = new CacheProperties();
        $cache->addProperty($start);
        $cache->addProperty($end);
        $cache->addProperty('chart.budget.budget');
        $cache->addProperty($budget->id);

        if ($cache->has()) {
            return response()->json($cache->get()); // @codeCoverageIgnore
        }

        $step             = $this->calculateStep($start, $end); // depending on diff, do something with range of chart.
        $budgetCollection = new Collection([$budget]);
        $chartData        = [];
        $current          = clone $start;
        $current          = app('navigation')->startOfPeriod($current, $step);
        while ($end >= $current) {
            /** @var Carbon $currentEnd */
            $currentEnd = app('navigation')->endOfPeriod($current, $step);
            if ('1Y' === $step) {
                $currentEnd->subDay(); // @codeCoverageIgnore
            }
            $spent             = $this->repository->spentInPeriod($budgetCollection, new Collection, $current, $currentEnd);
            $label             = app('navigation')->periodShow($current, $step);
            $chartData[$label] = (float)bcmul($spent, '-1');
            $current           = clone $currentEnd;
            $current->addDay();
        }

        $data = $this->generator->singleSet((string)trans('firefly.spent'), $chartData);

        $cache->store($data);

        return response()->json($data);
    }


    /**
     * Shows the amount left in a specific budget limit.
     *
     * TODO this chart is not multi-currency aware.
     *
     * @param Budget $budget
     * @param BudgetLimit $budgetLimit
     *
     * @return JsonResponse
     *
     * @throws FireflyException
     */
    public function budgetLimit(Budget $budget, BudgetLimit $budgetLimit): JsonResponse
    {
        if ($budgetLimit->budget->id !== $budget->id) {
            throw new FireflyException('This budget limit is not part of this budget.');
        }

        $start = clone $budgetLimit->start_date;
        $end   = clone $budgetLimit->end_date;
        $cache = new CacheProperties();
        $cache->addProperty($start);
        $cache->addProperty($end);
        $cache->addProperty('chart.budget.budget.limit');
        $cache->addProperty($budgetLimit->id);
        $cache->addProperty($budget->id);

        if ($cache->has()) {
            return response()->json($cache->get()); // @codeCoverageIgnore
        }

        $entries          = [];
        $amount           = $budgetLimit->amount;
        $budgetCollection = new Collection([$budget]);
        while ($start <= $end) {
            $spent            = $this->repository->spentInPeriod($budgetCollection, new Collection, $start, $start);
            $amount           = bcadd($amount, $spent);
            $format           = $start->formatLocalized((string)trans('config.month_and_day'));
            $entries[$format] = $amount;

            $start->addDay();
        }
        $data = $this->generator->singleSet((string)trans('firefly.left'), $entries);
        $cache->store($data);

        return response()->json($data);
    }


    /**
     * Shows how much is spent per asset account.
     *
     * TODO this chart is not multi-currency aware.
     *
     * @param Budget $budget
     * @param BudgetLimit|null $budgetLimit
     *
     * @return JsonResponse
     *
     * @SuppressWarnings(PHPMD.CyclomaticComplexity)
     */
    public function expenseAsset(Budget $budget, ?BudgetLimit $budgetLimit): JsonResponse
    {
        $budgetLimitId = null === $budgetLimit ? 0 : $budgetLimit->id;
        $cache         = new CacheProperties;
        $cache->addProperty($budget->id);
        $cache->addProperty($budgetLimitId);
        $cache->addProperty('chart.budget.expense-asset');
        if ($cache->has()) {
            return response()->json($cache->get()); // @codeCoverageIgnore
        }

        /** @var GroupCollectorInterface $collector */
        $collector = app(GroupCollectorInterface::class);
        $collector->setBudget($budget);
        if (null !== $budgetLimit) {
            $collector->setRange($budgetLimit->start_date, $budgetLimit->end_date);
        }

        $journals  = $collector->getExtractedJournals();
        $result    = [];
        $chartData = [];
        foreach ($journals as $journal) {
            $assetId          = (int)$journal['destination_account_id'];
            $result[$assetId] = $result[$assetId] ?? '0';
            $result[$assetId] = bcadd($journal['amount'], $result[$assetId]);
        }

        $names = $this->getAccountNames(array_keys($result));
        foreach ($result as $assetId => $amount) {
            $chartData[$names[$assetId]] = $amount;
        }

        $data = $this->generator->pieChart($chartData);
        $cache->store($data);

        return response()->json($data);
    }


    /**
     * Shows how much is spent per category.
     *
     * TODO this chart is not multi-currency aware.
     *
     * @param Budget $budget
     * @param BudgetLimit|null $budgetLimit
     *
     * @return JsonResponse
     *
     * @SuppressWarnings(PHPMD.CyclomaticComplexity)
     */
    public function expenseCategory(Budget $budget, ?BudgetLimit $budgetLimit): JsonResponse
    {
        $budgetLimitId = null === $budgetLimit ? 0 : $budgetLimit->id;
        $cache         = new CacheProperties;
        $cache->addProperty($budget->id);
        $cache->addProperty($budgetLimitId);
        $cache->addProperty('chart.budget.expense-category');
        if ($cache->has()) {
            return response()->json($cache->get()); // @codeCoverageIgnore
        }

        /** @var GroupCollectorInterface $collector */
        $collector = app(GroupCollectorInterface::class);
        $collector->setBudget($budget)->withCategoryInformation();
        if (null !== $budgetLimit) {
            $collector->setRange($budgetLimit->start_date, $budgetLimit->end_date);
        }

        $journals  = $collector->getExtractedJournals();
        $result    = [];
        $chartData = [];
        foreach ($journals as $journal) {
            $categoryId          = (int)$journal['category_id'];
            $result[$categoryId] = $result[$categoryId] ?? '0';
            $result[$categoryId] = bcadd($journal['amount'], $result[$categoryId]);
        }

        $names = $this->getCategoryNames(array_keys($result));
        foreach ($result as $categoryId => $amount) {
            $chartData[$names[$categoryId]] = $amount;
        }
        $data = $this->generator->pieChart($chartData);
        $cache->store($data);

        return response()->json($data);
    }


    /**
     * Shows how much is spent per expense account.
     *
     * TODO this chart is not multi-currency aware.
     *
     * @param Budget $budget
     * @param BudgetLimit|null $budgetLimit
     *
     * @return JsonResponse
     *
     * @SuppressWarnings(PHPMD.CyclomaticComplexity)
     */
    public function expenseExpense(Budget $budget, ?BudgetLimit $budgetLimit): JsonResponse
    {
        $budgetLimitId = null === $budgetLimit ? 0 : $budgetLimit->id;
        $cache         = new CacheProperties;
        $cache->addProperty($budget->id);
        $cache->addProperty($budgetLimitId);
        $cache->addProperty('chart.budget.expense-expense');
        if ($cache->has()) {
            return response()->json($cache->get()); // @codeCoverageIgnore
        }

        /** @var GroupCollectorInterface $collector */
        $collector = app(GroupCollectorInterface::class);

        $collector->setTypes([TransactionType::WITHDRAWAL])->setBudget($budget)->withAccountInformation();
        if (null !== $budgetLimit) {
            $collector->setRange($budgetLimit->start_date, $budgetLimit->end_date);
        }

        $journals  = $collector->getExtractedJournals();
        $result    = [];
        $chartData = [];
        /** @var array $journal */
        foreach ($journals as $journal) {
            $opposingId          = (int)$journal['destination_account_id'];
            $result[$opposingId] = $result[$opposingId] ?? '0';
            $result[$opposingId] = bcadd($journal['amount'], $result[$opposingId]);
        }

        $names = $this->getAccountNames(array_keys($result));
        foreach ($result as $opposingId => $amount) {
            $name             = $names[$opposingId] ?? 'no name';
            $chartData[$name] = $amount;
        }

        $data = $this->generator->pieChart($chartData);
        $cache->store($data);

        return response()->json($data);
    }


    /**
     * Shows a budget list with spent/left/overspent.
     *
     * TODO this chart is not multi-currency aware.
     *
     * @return JsonResponse
     *
     * @SuppressWarnings(PHPMD.CyclomaticComplexity)
     * @SuppressWarnings(PHPMD.ExcessiveMethodLength)
     */
    public function frontpage(): JsonResponse
    {
        $start = session('start', Carbon::now()->startOfMonth());
        $end   = session('end', Carbon::now()->endOfMonth());
        // chart properties for cache:
        $cache = new CacheProperties();
        $cache->addProperty($start);
        $cache->addProperty($end);
        $cache->addProperty('chart.budget.frontpage');
        if ($cache->has()) {
            return response()->json($cache->get()); // @codeCoverageIgnore
        }
        $budgets   = $this->repository->getActiveBudgets();
        $chartData = [
            ['label' => (string)trans('firefly.spent_in_budget'), 'entries' => [], 'type' => 'bar'],
            ['label' => (string)trans('firefly.left_to_spend'), 'entries' => [], 'type' => 'bar'],
            ['label' => (string)trans('firefly.overspent'), 'entries' => [], 'type' => 'bar'],
        ];

        /** @var Budget $budget */
        foreach ($budgets as $budget) {
            // get relevant repetitions:
            $limits   = $this->repository->getBudgetLimits($budget, $start, $end);
            $expenses = $this->getExpensesForBudget($limits, $budget, $start, $end);

            foreach ($expenses as $name => $row) {
                $chartData[0]['entries'][$name] = $row['spent'];
                $chartData[1]['entries'][$name] = $row['left'];
                $chartData[2]['entries'][$name] = $row['overspent'];
            }
        }
        // for no budget:
        $spent = $this->spentInPeriodWithout($start, $end);
        $name  = (string)trans('firefly.no_budget');
        if (0 !== bccomp($spent, '0')) {
            $chartData[0]['entries'][$name] = bcmul($spent, '-1');
            $chartData[1]['entries'][$name] = '0';
            $chartData[2]['entries'][$name] = '0';
        }

        $data = $this->generator->multiSet($chartData);
        $cache->store($data);

        return response()->json($data);
    }

    /** @noinspection MoreThanThreeArgumentsInspection */
    /**
     * Shows a budget overview chart (spent and budgeted).
     *
     * TODO this chart is not multi-currency aware.
     *
     * @param Budget $budget
     * @param Carbon $start
     * @param Carbon $end
     * @param Collection $accounts
     *
     * @return JsonResponse
     */
    public function period(Budget $budget, Collection $accounts, Carbon $start, Carbon $end): JsonResponse
    {
        // chart properties for cache:
        $cache = new CacheProperties();
        $cache->addProperty($start);
        $cache->addProperty($end);
        $cache->addProperty($accounts);
        $cache->addProperty($budget->id);
        $cache->addProperty('chart.budget.period');
        if ($cache->has()) {
            return response()->json($cache->get()); // @codeCoverageIgnore
        }
        $periods  = app('navigation')->listOfPeriods($start, $end);
        $entries  = $this->repository->getBudgetPeriodReport(new Collection([$budget]), $accounts, $start, $end); // get the expenses
        $budgeted = $this->getBudgetedInPeriod($budget, $start, $end);

        // join them into one set of data:
        $chartData = [
            ['label' => (string)trans('firefly.spent'), 'type' => 'bar', 'entries' => []],
            ['label' => (string)trans('firefly.budgeted'), 'type' => 'bar', 'entries' => []],
        ];

        foreach (array_keys($periods) as $period) {
            $label                           = $periods[$period];
            $spent                           = $entries[$budget->id]['entries'][$period] ?? '0';
            $limit                           = (int)($budgeted[$period] ?? 0);
            $chartData[0]['entries'][$label] = round(bcmul($spent, '-1'), 12);
            $chartData[1]['entries'][$label] = $limit;
        }
        $data = $this->generator->multiSet($chartData);
        $cache->store($data);

        return response()->json($data);
    }


    /**
     * Shows a chart for transactions without a budget.
     *
     * TODO this chart is not multi-currency aware.
     *
     * @param Collection $accounts
     * @param Carbon $start
     * @param Carbon $end
     *
     * @return JsonResponse
     */
    public function periodNoBudget(Collection $accounts, Carbon $start, Carbon $end): JsonResponse
    {
        // chart properties for cache:
        $cache = new CacheProperties();
        $cache->addProperty($start);
        $cache->addProperty($end);
        $cache->addProperty($accounts);
        $cache->addProperty('chart.budget.no-budget');
        if ($cache->has()) {
            return response()->json($cache->get()); // @codeCoverageIgnore
        }

        // the expenses:
        $periods   = app('navigation')->listOfPeriods($start, $end);
        $entries   = $this->repository->getNoBudgetPeriodReport($accounts, $start, $end);
        $chartData = [];

        // join them:
        foreach (array_keys($periods) as $period) {
            $label             = $periods[$period];
            $spent             = $entries['entries'][$period] ?? '0';
            $chartData[$label] = bcmul($spent, '-1');
        }
        $data = $this->generator->singleSet((string)trans('firefly.spent'), $chartData);
        $cache->store($data);

        return response()->json($data);
    }


}