<?php
/**
 * webtrees: online genealogy
 * Copyright (C) 2018 webtrees development team
 * This program 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.
 * 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 General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
declare(strict_types=1);

namespace Fisharebest\Webtrees\Http\Controllers;

use Fisharebest\ExtCalendar\GregorianCalendar;
use Fisharebest\Webtrees\ColorGenerator;
use Fisharebest\Webtrees\Database;
use Fisharebest\Webtrees\Date;
use Fisharebest\Webtrees\I18N;
use Fisharebest\Webtrees\Individual;
use Fisharebest\Webtrees\Place;
use Fisharebest\Webtrees\Tree;
use stdClass;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

/**
 * A chart showing the lifespans of individuals.
 */
class LifespansChartController extends AbstractChartController
{
    // Parameters for generating colors
    const RANGE      = 120; // degrees
    const SATURATION = 100; // percent
    const LIGHTNESS  = 30; // percent
    const ALPHA      = 0.25;

    /**
     * A form to request the chart parameters.
     *
     * @param Request $request
     * @param Tree    $tree
     *
     * @return Response
     */
    public function page(Request $request, Tree $tree): Response
    {
        $this->checkModuleIsActive($tree, 'lifespans_chart');

        $xrefs     = (array) $request->get('xrefs', []);
        $addxref   = $request->get('addxref', '');
        $addfam    = (bool) $request->get('addfam', false);
        $placename = $request->get('placename', '');
        $start     = $request->get('start', '');
        $end       = $request->get('end', '');

        $place      = new Place($placename, $tree);
        $start_date = new Date($start);
        $end_date   = new Date($end);

        // Add an individual, and family members
        $individual = Individual::getInstance($addxref, $tree);
        if ($individual !== null) {
            $xrefs[] = $addxref;
            if ($addfam) {
                $xrefs = array_merge($xrefs, $this->closeFamily($individual));
            }
        }

        // Select by date and/or place.
        if ($start_date->isOK() && $end_date->isOK() && $placename !== '') {
            $date_xrefs  = $this->findIndividualsByDate($start_date, $end_date, $tree);
            $place_xrefs = $this->findIndividualsByPlace($place, $tree);
            $xrefs       = array_intersect($date_xrefs, $place_xrefs);
        } elseif ($start_date->isOK() && $end_date->isOK()) {
            $xrefs = $this->findIndividualsByDate($start_date, $end_date, $tree);
        } elseif ($placename !== '') {
            $xrefs = $this->findIndividualsByPlace($place, $tree);
        }

        // Filter duplicates and private individuals.
        $xrefs = array_unique($xrefs);
        $xrefs = array_filter($xrefs, function (string $xref) use ($tree): bool {
            $individual = Individual::getInstance($xref, $tree);

            return $individual !== null && $individual->canShow();
        });

        $title    = I18N::translate('Lifespans');
        $subtitle = $this->subtitle(count($xrefs), $start_date, $end_date, $placename);

        return $this->viewResponse('lifespans-page', [
            'xrefs'    => $xrefs,
            'subtitle' => $subtitle,
            'title'    => $title,
        ]);
    }

    /**
     * @param Request $request
     * @param Tree    $tree
     *
     * @return Response
     */
    public function chart(Request $request, Tree $tree): Response
    {
        $this->checkModuleIsActive($tree, 'lifespans_chart');

        $xrefs = (array) $request->get('xrefs', []);
        $xrefs = array_unique($xrefs);

        /** @var Individual[] $individuals */
        $individuals = array_map(function (string $xref) use ($tree) {
            return Individual::getInstance($xref, $tree);
        }, $xrefs);

        $individuals = array_filter($individuals, function (Individual $individual = null): bool {
            return $individual !== null && $individual->canShow();
        });

        // Sort the array in order of birth year
        usort($individuals, function (Individual $a, Individual $b) {
            return Date::compare($a->getEstimatedBirthDate(), $b->getEstimatedBirthDate());
        });

        $subtitle = $request->get('subtitle');

        // Round to whole decades
        $start_year = (int) floor($this->minYear($individuals) / 10) * 10;
        $end_year   = (int) ceil($this->maxYear($individuals) / 10) * 10;

        $lifespans = $this->layoutIndividuals($individuals);

        $max_rows = array_reduce($lifespans, function ($carry, stdClass $item) {
            return max($carry, $item->row);
        }, 0);

        $html = view('lifespans-chart', [
            'dir'        => I18N::direction(),
            'end_year'   => $end_year,
            'lifespans'  => $lifespans,
            'max_rows'   => $max_rows,
            'start_year' => $start_year,
            'subtitle'   => $subtitle,
        ]);

        return new Response($html);
    }

    /**
     *
     *
     * @param Individual[] $individuals
     *
     * @return stdClass[]
     */
    private function layoutIndividuals(array $individuals): array
    {
        $colors = [
            'M' => new ColorGenerator(240, self::SATURATION, self::LIGHTNESS, self::ALPHA, self::RANGE * -1),
            'F' => new ColorGenerator(000, self::SATURATION, self::LIGHTNESS, self::ALPHA, self::RANGE),
            'U' => new ColorGenerator(120, self::SATURATION, self::LIGHTNESS, self::ALPHA, self::RANGE),
        ];

        $current_year = (int) date('Y');

        // Latest year used in each row
        $rows = [];

        $lifespans = [];

        foreach ($individuals as $individual) {
            $birth_jd   = $individual->getEstimatedBirthDate()->minimumJulianDay();
            $birth_year = $this->jdToYear($birth_jd);
            $death_jd   = $individual->getEstimatedDeathDate()->maximumJulianDay();
            $death_year = $this->jdToYear($death_jd);

            // Don't show death dates in the future.
            $death_year = min($death_year, $current_year);

            // Add this individual to the next row in the chart...
            $next_row = count($rows);
            // ...unless we can find an existing row where it fits.
            foreach ($rows as $row => $year) {
                if ($year < $birth_year) {
                    $next_row = $row;
                    break;
                }
            }

            // Fill the row up to the year (leaving a small gap)
            $rows[$next_row] = $death_year;

            $lifespans[] = (object) [
                'background' => $colors[$individual->getSex()]->getNextColor(),
                'birth_year' => $birth_year,
                'death_year' => $death_year,
                'id'         => 'individual-' . md5($individual->xref()),
                'individual' => $individual,
                'row'        => $next_row,
            ];
        }

        return $lifespans;
    }

    /**
     * Find the latest event year for individuals
     *
     * @param array $individuals
     *
     * @return int
     */
    private function maxYear(array $individuals): int
    {
        $jd = array_reduce($individuals, function ($carry, Individual $item) {
            return max($carry, $item->getEstimatedDeathDate()->maximumJulianDay());
        }, 0);

        $year = $this->jdToYear($jd);

        // Don't show future dates
        return min($year, (int) date('Y'));
    }

    /**
     * Find the earliest event year for individuals
     *
     * @param array $individuals
     *
     * @return int
     */
    private function minYear(array $individuals): int
    {
        $jd = array_reduce($individuals, function ($carry, Individual $item) {
            return min($carry, $item->getEstimatedBirthDate()->minimumJulianDay());
        }, PHP_INT_MAX);

        return $this->jdToYear($jd);
    }

    /**
     * Convert a julian day to a gregorian year
     *
     * @param int $jd
     *
     * @return int
     */
    private function jdToYear(int $jd): int
    {
        if ($jd === 0) {
            return 0;
        }

        $gregorian = new GregorianCalendar();
        [$y] = $gregorian->jdToYmd($jd);

        return $y;
    }

    /**
     * @param Date $start
     * @param Date $end
     * @param Tree $tree
     *
     * @return string[]
     */
    private function findIndividualsByDate(Date $start, Date $end, Tree $tree): array
    {
        return Database::prepare(
            "SELECT d_gid" .
            " FROM `##dates`" .
            " WHERE d_file = :tree_id" .
            " AND d_julianday1 <= :max_jd" .
            " AND d_julianday2 >= :min_jd" .
            " AND d_fact NOT IN ('BAPL', 'ENDL', 'SLGC', 'SLGS', '_TODO', 'CHAN')"
        )->execute([
            'tree_id' => $tree->id(),
            'max_jd'  => $end->maximumJulianDay(),
            'min_jd'  => $start->minimumJulianDay(),
        ])->fetchOneColumn();
    }

    /**
     * @param Place $place
     * @param Tree  $tree
     *
     * @return string[]
     */
    private function findIndividualsByPlace(Place $place, Tree $tree): array
    {
        return Database::prepare(
            "SELECT DISTINCT `i_id` FROM `##placelinks`" .
            " JOIN `##individuals` ON `pl_gid`=`i_id` AND `pl_file`=`i_file`" .
            " WHERE `i_file`=:tree_id" .
            " AND `pl_p_id`=:place_id" .
            " UNION" .
            " SELECT DISTINCT `f_id` FROM `##placelinks`" .
            " JOIN `##families` ON `pl_gid`=`f_id` AND `pl_file`=`f_file`" .
            " WHERE `f_file`=:tree_id" .
            " AND `pl_p_id`=:place_id"
        )->execute([
            'tree_id'  => $tree->id(),
            'place_id' => $place->getPlaceId(),
        ])->fetchOneColumn();
    }

    /**
     * Find the close family members of an individual.
     *
     * @param Individual $individual
     *
     * @return string[]
     */
    private function closeFamily(Individual $individual): array
    {
        $xrefs = [];

        foreach ($individual->getSpouseFamilies() as $family) {
            foreach ($family->getChildren() as $child) {
                $xrefs[] = $child->xref();
            }

            foreach ($family->getSpouses() as $spouse) {
                $xrefs[] = $spouse->xref();
            }
        }

        foreach ($individual->getChildFamilies() as $family) {
            foreach ($family->getChildren() as $child) {
                $xrefs[] = $child->xref();
            }

            foreach ($family->getSpouses() as $spouse) {
                $xrefs[] = $spouse->xref();
            }
        }

        return $xrefs;
    }

    /**
     * Generate a subtitle, based on filter parameters
     *
     * @param int    $count
     * @param Date   $start
     * @param Date   $end
     * @param string $placename
     *
     * @return string
     */
    private function subtitle(int $count, Date $start, Date $end, string $placename): string
    {
        if ($start->isOK() && $end->isOK() && $placename !== '') {
            return I18N::plural(
                '%s individual with events in %s between %s and %s',
                '%s individuals with events in %s between %s and %s',
                $count,
                I18N::number($count),
                $placename,
                $start->display(false, '%Y'),
                $end->display(false, '%Y')
            );
        }

        if ($placename !== '') {
            return I18N::plural(
                '%s individual with events in %s',
                '%s individuals with events in %s',
                $count,
                I18N::number($count),
                $placename
            );
        }

        if ($start->isOK() && $end->isOK()) {
            return I18N::plural(
                '%s individual with events between %s and %s',
                '%s individuals with events between %s and %s',
                $count,
                I18N::number($count),
                $start->display(false, '%Y'),
                $end->display(false, '%Y')
            );
        }

        return I18N::plural('%s individual', '%s individuals', $count, I18N::number($count));
    }
}
