<?php
/**
 * BudgetRepository.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\Repositories\Budget;

use Carbon\Carbon;
use Exception;
use FireflyIII\Exceptions\FireflyException;
use FireflyIII\Factory\TransactionCurrencyFactory;
use FireflyIII\Helpers\Collector\GroupCollectorInterface;
use FireflyIII\Models\AvailableBudget;
use FireflyIII\Models\Budget;
use FireflyIII\Models\BudgetLimit;
use FireflyIII\Models\RuleAction;
use FireflyIII\Models\RuleTrigger;
use FireflyIII\Models\TransactionCurrency;
use FireflyIII\Models\TransactionType;
use FireflyIII\Services\Internal\Destroy\BudgetDestroyService;
use FireflyIII\User;
use Illuminate\Support\Collection;
use Log;
use Navigation;

/**
 * Class BudgetRepository.
 *
 */
class BudgetRepository implements BudgetRepositoryInterface
{
    /** @var User */
    private $user;

    /**
     * Constructor.
     */
    public function __construct()
    {
        if ('testing' === config('app.env')) {
            Log::warning(sprintf('%s should not be instantiated in the TEST environment!', get_class($this)));
        }
    }

    /**
     * @return bool
     *  // it's 5.
     */
    public function cleanupBudgets(): bool
    {
        // delete limits with amount 0:
        try {
            BudgetLimit::where('amount', 0)->delete();
        } catch (Exception $e) {
            Log::debug(sprintf('Could not delete budget limit: %s', $e->getMessage()));
        }
        Budget::where('order', 0)->update(['order' => 100]);

        // do the clean up by hand because Sqlite can be tricky with this.
        $budgetLimits = BudgetLimit::orderBy('created_at', 'DESC')->get(['id', 'budget_id', 'start_date', 'end_date']);
        $count        = [];
        /** @var BudgetLimit $budgetLimit */
        foreach ($budgetLimits as $budgetLimit) {
            $key = $budgetLimit->budget_id . '-' . $budgetLimit->start_date->format('Y-m-d') . $budgetLimit->end_date->format('Y-m-d');
            if (isset($count[$key])) {
                // delete it!
                try {
                    BudgetLimit::find($budgetLimit->id)->delete();
                } catch (Exception $e) {
                    Log::debug(sprintf('Could not delete budget limit: %s', $e->getMessage()));
                }
            }
            $count[$key] = true;
        }

        return true;
    }

    /**
     * @param Budget $budget
     *
     * @return bool
     */
    public function destroy(Budget $budget): bool
    {
        /** @var BudgetDestroyService $service */
        $service = app(BudgetDestroyService::class);
        $service->destroy($budget);

        return true;
    }

    /**
     * @param int|null    $budgetId
     * @param string|null $budgetName
     *
     * @return Budget|null
     */
    public function findBudget(?int $budgetId, ?string $budgetName): ?Budget
    {
        Log::debug('Now in findBudget()');
        Log::debug(sprintf('Searching for budget with ID #%d...', $budgetId));
        $result = $this->findNull((int)$budgetId);
        if (null === $result && null !== $budgetName && '' !== $budgetName) {
            Log::debug(sprintf('Searching for budget with name %s...', $budgetName));
            $result = $this->findByName((string)$budgetName);
        }
        if (null !== $result) {
            Log::debug(sprintf('Found budget #%d: %s', $result->id, $result->name));
        }
        Log::debug(sprintf('Found result is null? %s', var_export(null === $result, true)));

        return $result;
    }

    /**
     * Find budget by name.
     *
     * @param string|null $name
     *
     * @return Budget|null
     */
    public function findByName(?string $name): ?Budget
    {
        if (null === $name) {
            return null;
        }
        $query = sprintf('%%%s%%', $name);

        return $this->user->budgets()->where('name', 'LIKE', $query)->first();
    }

    /**
     * Find a budget or return NULL
     *
     * @param int $budgetId |null
     *
     * @return Budget|null
     */
    public function findNull(int $budgetId = null): ?Budget
    {
        if (null === $budgetId) {
            return null;
        }

        return $this->user->budgets()->find($budgetId);
    }

    /**
     * This method returns the oldest journal or transaction date known to this budget.
     * Will cache result.
     *
     * @param Budget $budget
     *
     * @return Carbon
     *
     */
    public function firstUseDate(Budget $budget): ?Carbon
    {
        $oldest  = null;
        $journal = $budget->transactionJournals()->orderBy('date', 'ASC')->first();
        if (null !== $journal) {
            $oldest = $journal->date < $oldest ? $journal->date : $oldest;
        }

        $transaction = $budget
            ->transactions()
            ->leftJoin('transaction_journals', 'transaction_journals.id', '=', 'transactions.id')
            ->orderBy('transaction_journals.date', 'ASC')->first(['transactions.*', 'transaction_journals.date']);
        if (null !== $transaction) {
            $carbon = new Carbon($transaction->date);
            $oldest = $carbon < $oldest ? $carbon : $oldest;
        }

        return $oldest;
    }

    /**
     * @return Collection
     */
    public function getActiveBudgets(): Collection
    {
        /** @var Collection $set */
        $set = $this->user->budgets()->where('active', 1)
                          ->orderBy('order', 'DESC')
                          ->orderBy('name', 'ASC')
                          ->get();

        return $set;
    }

    /**
     * @return Collection
     */
    public function getBudgets(): Collection
    {
        /** @var Collection $set */
        $set = $this->user->budgets()->orderBy('order', 'DESC')
                          ->orderBy('name', 'ASC')->get();

        return $set;
    }

    /**
     * Get all budgets with these ID's.
     *
     * @param array $budgetIds
     *
     * @return Collection
     */
    public function getByIds(array $budgetIds): Collection
    {
        return $this->user->budgets()->whereIn('id', $budgetIds)->get();
    }

    /**
     * @return Collection
     */
    public function getInactiveBudgets(): Collection
    {
        /** @var Collection $set */
        $set = $this->user->budgets()->orderBy('order', 'DESC')
                          ->orderBy('name', 'ASC')->where('active', 0)->get();

        return $set;
    }

    /**
     * @param string $query
     *
     * @return Collection
     */
    public function searchBudget(string $query): Collection
    {

        $search = $this->user->budgets();
        if ('' !== $query) {
            $search->where('name', 'LIKE', sprintf('%%%s%%', $query));
        }

        return $search->get();
    }

    /**
     * @param Budget $budget
     * @param int    $order
     */
    public function setBudgetOrder(Budget $budget, int $order): void
    {
        $budget->order = $order;
        $budget->save();
    }

    /**
     * @param User $user
     */
    public function setUser(User $user): void
    {
        $this->user = $user;
    }

    /**
     * @param array $data
     *
     * @return Budget
     */
    public function store(array $data): Budget
    {
        $newBudget = new Budget(
            [
                'user_id' => $this->user->id,
                'name'    => $data['name'],
            ]
        );
        $newBudget->save();

        return $newBudget;
    }

    /**
     * @param array $data
     *
     * @return BudgetLimit
     */
    public function storeBudgetLimit(array $data): BudgetLimit
    {
        $this->cleanupBudgets();
        /** @var Budget $budget */
        $budget = $data['budget'];

        // if no currency has been provided, use the user's default currency:
        /** @var TransactionCurrencyFactory $factory */
        $factory  = app(TransactionCurrencyFactory::class);
        $currency = $factory->find($data['currency_id'] ?? null, $data['currency_code'] ?? null);
        if (null === $currency) {
            $currency = app('amount')->getDefaultCurrencyByUser($this->user);
        }

        // find limit with same date range.
        // if it exists, return that one.
        $limit = $budget->budgetlimits()
                        ->where('budget_limits.start_date', $data['start']->format('Y-m-d 00:00:00'))
                        ->where('budget_limits.end_date', $data['end']->format('Y-m-d 00:00:00'))
                        ->where('budget_limits.transaction_currency_id', $currency->id)
                        ->get(['budget_limits.*'])->first();
        if (null !== $limit) {
            return $limit;
        }
        Log::debug('No existing budget limit, create a new one');

        // or create one and return it.
        $limit = new BudgetLimit;
        $limit->budget()->associate($budget);
        $limit->start_date              = $data['start']->format('Y-m-d 00:00:00');
        $limit->end_date                = $data['end']->format('Y-m-d 00:00:00');
        $limit->amount                  = $data['amount'];
        $limit->transaction_currency_id = $currency->id;
        $limit->save();
        Log::debug(sprintf('Created new budget limit with ID #%d and amount %s', $limit->id, $data['amount']));

        return $limit;
    }

    /**
     * @param Budget $budget
     * @param array  $data
     *
     * @return Budget
     */
    public function update(Budget $budget, array $data): Budget
    {
        $oldName        = $budget->name;
        $budget->name   = $data['name'];
        $budget->active = $data['active'];
        $budget->save();
        $this->updateRuleTriggers($oldName, $data['name']);
        $this->updateRuleActions($oldName, $data['name']);
        app('preferences')->mark();

        return $budget;
    }

    /**
     * TODO only used in the API.
     *
     * @param AvailableBudget $availableBudget
     * @param array           $data
     *
     * @return AvailableBudget
     * @throws FireflyException
     */
    public function updateAvailableBudget(AvailableBudget $availableBudget, array $data): AvailableBudget
    {
        $existing = $this->user->availableBudgets()
                               ->where('transaction_currency_id', $data['currency_id'])
                               ->where('start_date', $data['start']->format('Y-m-d 00:00:00'))
                               ->where('end_date', $data['end']->format('Y-m-d 00:00:00'))
                               ->where('id', '!=', $availableBudget->id)
                               ->first();

        if (null !== $existing) {
            throw new FireflyException(sprintf('An entry already exists for these parameters: available budget object with ID #%d', $existing->id));
        }
        $availableBudget->transaction_currency_id = $data['currency_id'];
        $availableBudget->start_date              = $data['start'];
        $availableBudget->end_date                = $data['end'];
        $availableBudget->amount                  = $data['amount'];
        $availableBudget->save();

        return $availableBudget;

    }

    /**
     * @param BudgetLimit $budgetLimit
     * @param array       $data
     *
     * @return BudgetLimit
     * @throws Exception
     */
    public function updateBudgetLimit(BudgetLimit $budgetLimit, array $data): BudgetLimit
    {
        $this->cleanupBudgets();
        /** @var Budget $budget */
        $budget = $data['budget'];

        $budgetLimit->budget()->associate($budget);
        $budgetLimit->start_date = $data['start']->format('Y-m-d 00:00:00');
        $budgetLimit->end_date   = $data['end']->format('Y-m-d 00:00:00');
        $budgetLimit->amount     = $data['amount'];

        // if no currency has been provided, use the user's default currency:
        /** @var TransactionCurrencyFactory $factory */
        $factory  = app(TransactionCurrencyFactory::class);
        $currency = $factory->find($data['currency_id'] ?? null, $data['currency_code'] ?? null);
        if (null === $currency) {
            $currency = app('amount')->getDefaultCurrencyByUser($this->user);
        }
        $currency->enabled = true;
        $currency->save();
        $budgetLimit->transaction_currency_id = $currency->id;

        $budgetLimit->save();
        Log::debug(sprintf('Updated budget limit with ID #%d and amount %s', $budgetLimit->id, $data['amount']));

        return $budgetLimit;
    }

    /**
     * @param Budget $budget
     * @param Carbon $start
     * @param Carbon $end
     * @param string $amount
     *
     * @return BudgetLimit|null
     *
     */
    public function updateLimitAmount(Budget $budget, Carbon $start, Carbon $end, string $amount): ?BudgetLimit
    {
        $this->cleanupBudgets();
        // count the limits:
        $limits = $budget->budgetlimits()
                         ->where('budget_limits.start_date', $start->format('Y-m-d 00:00:00'))
                         ->where('budget_limits.end_date', $end->format('Y-m-d 00:00:00'))
                         ->get(['budget_limits.*'])->count();
        Log::debug(sprintf('Found %d budget limits.', $limits));

        // there might be a budget limit for these dates:
        /** @var BudgetLimit $limit */
        $limit = $budget->budgetlimits()
                        ->where('budget_limits.start_date', $start->format('Y-m-d 00:00:00'))
                        ->where('budget_limits.end_date', $end->format('Y-m-d 00:00:00'))
                        ->first(['budget_limits.*']);

        // if more than 1 limit found, delete the others:
        if ($limits > 1 && null !== $limit) {
            Log::debug(sprintf('Found more than 1, delete all except #%d', $limit->id));
            $budget->budgetlimits()
                   ->where('budget_limits.start_date', $start->format('Y-m-d 00:00:00'))
                   ->where('budget_limits.end_date', $end->format('Y-m-d 00:00:00'))
                   ->where('budget_limits.id', '!=', $limit->id)->delete();
        }

        // delete if amount is zero.
        // Returns 0 if the two operands are equal,
        // 1 if the left_operand is larger than the right_operand, -1 otherwise.
        if (null !== $limit && bccomp($amount, '0') <= 0) {
            Log::debug(sprintf('%s is zero, delete budget limit #%d', $amount, $limit->id));
            try {
                $limit->delete();
            } catch (Exception $e) {
                Log::debug(sprintf('Could not delete limit: %s', $e->getMessage()));
            }


            return null;
        }
        // update if exists:
        if (null !== $limit) {
            Log::debug(sprintf('Existing budget limit is #%d, update this to amount %s', $limit->id, $amount));
            $limit->amount = $amount;
            $limit->save();

            return $limit;
        }
        Log::debug('No existing budget limit, create a new one');
        // or create one and return it.
        $limit = new BudgetLimit;
        $limit->budget()->associate($budget);
        $limit->start_date = $start->startOfDay();
        $limit->end_date   = $end->startOfDay();
        $limit->amount     = $amount;
        $limit->save();
        Log::debug(sprintf('Created new budget limit with ID #%d and amount %s', $limit->id, $amount));

        return $limit;
    }

    /**
     * @param string $oldName
     * @param string $newName
     */
    private function updateRuleActions(string $oldName, string $newName): void
    {
        $types   = ['set_budget',];
        $actions = RuleAction::leftJoin('rules', 'rules.id', '=', 'rule_actions.rule_id')
                             ->where('rules.user_id', $this->user->id)
                             ->whereIn('rule_actions.action_type', $types)
                             ->where('rule_actions.action_value', $oldName)
                             ->get(['rule_actions.*']);
        Log::debug(sprintf('Found %d actions to update.', $actions->count()));
        /** @var RuleAction $action */
        foreach ($actions as $action) {
            $action->action_value = $newName;
            $action->save();
            Log::debug(sprintf('Updated action %d: %s', $action->id, $action->action_value));
        }
    }

    /**
     * @param string $oldName
     * @param string $newName
     */
    private function updateRuleTriggers(string $oldName, string $newName): void
    {
        $types    = ['budget_is',];
        $triggers = RuleTrigger::leftJoin('rules', 'rules.id', '=', 'rule_triggers.rule_id')
                               ->where('rules.user_id', $this->user->id)
                               ->whereIn('rule_triggers.trigger_type', $types)
                               ->where('rule_triggers.trigger_value', $oldName)
                               ->get(['rule_triggers.*']);
        Log::debug(sprintf('Found %d triggers to update.', $triggers->count()));
        /** @var RuleTrigger $trigger */
        foreach ($triggers as $trigger) {
            $trigger->trigger_value = $newName;
            $trigger->save();
            Log::debug(sprintf('Updated trigger %d: %s', $trigger->id, $trigger->trigger_value));
        }
    }
}