<?php
/**
 * 日历 / 日程（v14 新模块，导航条上叫「日程」）。
 *
 * 三条核心设计（用户 2026-10-01 第 7 条逐条对应）：
 *   ① **每人可建日历本**（自定义名字 + 自定义颜色），并能共享给别人（只读 / 可写）。
 *   ② **观影与旅行是每人默认的两本**，名字就叫「观影」「旅行」，内容**从 events 派生** ——
 *      不复制一份进 calendar_events，否则"改了观影记录、日历还是旧的"。
 *      反过来，在日历里给观影本新增日程 = 写一条 events(kind='movie')（真的成为一条观影记录）。
 *   ③ **没有具体时分的日程 = 全天日程**（all_day=1）。
 *
 * 日历其实是"综合视图"：自定义日程 + 观影 + 旅行 + 有截止时间的任务，
 * 各模块各自出数据，日历只负责按日期摆出来（见 Calendar::month()）。
 */

declare(strict_types=1);

namespace App;

final class Calendar
{
    /** 系统预置的两本默认日历（kind 与名字都写死，用户的自定义本一律 kind='custom'） */
    public const DEFAULT_KINDS = [
        'movie' => ['观影', '#7A4E8C'],
        'trip'  => ['旅行', '#3F7D5A'],
    ];

    /**
     * 建本时的预设色板（与影院管理同一个交互：取色器 + 点一下就换）。
     *
     * ⚠️ 一律挑**中低饱和**的：月网格里日程条是**白字压在色块上**，
     *    太浅看不清字，太艳会盖过整个月视图。
     */
    public const PRESET_CAL_COLORS = [
        '#4A7C82', '#7A4E8C', '#3F7D5A', '#B0763A', '#5566A8',
        '#A8574F', '#8A6B4B', '#5C8A48', '#9A5C7A', '#3D6B8E',
        '#8C7A3F', '#6B5B95',
    ];

    /** 新建一本 */
    public static function create(int $familyId, int $ownerId, string $name, string $color, string $kind = 'custom'): int
    {
        $db = Database::get();
        $db->prepare(
            'INSERT INTO calendars (family_id, owner_id, name, color, kind, position) VALUES (?,?,?,?,?,?)'
        )->execute([
            $familyId, $ownerId, mb_substr(trim($name), 0, 50, 'UTF-8'),
            // ⚠️ 统一**大写** hex：normalize() 会小写化，而我读回来的颜色要跟
            //    常量里的 '#7A4E8C' 之类直接比字符串（日历本颜色是给页面用的，
            //    大小写混着存会让"颜色一样吗"这种判断时对时错）。
            strtoupper(AvatarColor::normalize($color) ?: '#4A7C82'),
            $kind === 'movie' || $kind === 'trip' ? $kind : 'custom',
            self::nextPosition($ownerId),
        ]);
        return (int)$db->lastInsertId();
    }

    public static function update(int $id, string $name, string $color): void
    {
        Database::get()->prepare('UPDATE calendars SET name = ?, color = ? WHERE id = ?')
            ->execute([
                mb_substr(trim($name), 0, 50, 'UTF-8'),
                strtoupper(AvatarColor::normalize($color) ?: '#4A7C82'),
                $id,
            ]);
    }

    /** 删一本（默认本不许删 —— 删了观影/旅行就再也回不来了） */
    public static function delete(int $id): void
    {
        Database::get()->prepare("DELETE FROM calendars WHERE id = ? AND kind = 'custom'")->execute([$id]);
    }

    public static function find(int $id): ?array
    {
        $st = Database::get()->prepare('SELECT * FROM calendars WHERE id = ?');
        $st->execute([$id]);
        $r = $st->fetch();
        return $r ?: null;
    }

    /**
     * 我能看到的日历本 = 我自己的 + 别人共享给我的（带上我对它的权限）。
     *
     * `perm` 的含义：'owner'（我的，想怎么改都行）/ 'write' / 'read'。
     */
    public static function mine(int $familyId, int $personId): array
    {
        // ⚠️ 共享给我的本子也要带上**主人是谁**（页面要显示"谁共享给我的"），
        //    而且按"我看他叫什么"显示（owner_nick）—— 用户第 3 条。
        $st = Database::get()->prepare(
            "SELECT c.*, 'owner' AS perm, 0 AS shared,
                    p.name AS owner_name, p.avatar AS owner_avatar, p.avatar_color AS owner_color,
                    n.nickname AS owner_nick
               FROM calendars c
               JOIN persons p ON p.id = c.owner_id
               LEFT JOIN nicknames n ON n.target_id = c.owner_id AND n.viewer_id = ?
              WHERE c.family_id = ? AND c.owner_id = ?
             UNION ALL
             SELECT c.*, s.perm AS perm, 1 AS shared,
                    p.name AS owner_name, p.avatar AS owner_avatar, p.avatar_color AS owner_color,
                    n.nickname AS owner_nick
               FROM calendar_shares s
               JOIN calendars c ON c.id = s.calendar_id
               JOIN persons p ON p.id = c.owner_id
               LEFT JOIN nicknames n ON n.target_id = c.owner_id AND n.viewer_id = ?
              WHERE s.person_id = ? AND c.family_id = ?
              ORDER BY kind = 'custom', position, id"
        );
        $st->execute([$personId, $familyId, $personId, $personId, $personId, $familyId]);
        return $st->fetchAll();
    }

    /** 这本日历我能写吗（owner 或共享为 write） */
    public static function canWrite(array $cal, int $personId): bool
    {
        if ((int)$cal['owner_id'] === $personId) {
            return true;
        }
        return ($cal['perm'] ?? '') === 'write';
    }

    /** 给某人补建两本默认日历（幂等） */
    public static function seedDefaults(int $familyId, int $personId): void
    {
        foreach (self::DEFAULT_KINDS as $kind => list($name, $color)) {
            $st = Database::get()->prepare(
                'SELECT id FROM calendars WHERE owner_id = ? AND kind = ? AND name = ?'
            );
            $st->execute([$personId, $kind, $name]);
            if ($st->fetchColumn() === false) {
                self::create($familyId, $personId, $name, $color, $kind);
            }
        }
    }

    /** 升级 / 安装时给全家每个账号补一遍（老库也要有这两本） */
    public static function seedDefaultsForFamily(int $familyId): void
    {
        $st = Database::get()->prepare(
            "SELECT p.id FROM persons p JOIN accounts a ON a.person_id = p.id
              WHERE p.family_id = ? AND a.status = 'active'"
        );
        $st->execute([$familyId]);
        foreach ($st->fetchAll() as $r) {
            self::seedDefaults($familyId, (int)$r['id']);
        }
    }

    // ---------------- 共享 ----------------

    public static function shares(int $calendarId): array
    {
        $st = Database::get()->prepare(
            'SELECT s.person_id, s.perm, p.name, p.avatar, p.avatar_color
               FROM calendar_shares s JOIN persons p ON p.id = s.person_id
              WHERE s.calendar_id = ? ORDER BY p.id'
        );
        $st->execute([$calendarId]);
        return $st->fetchAll();
    }

    public static function setShare(int $calendarId, int $personId, string $perm): void
    {
        Database::get()->prepare(
            'INSERT INTO calendar_shares (calendar_id, person_id, perm) VALUES (?,?,?)
             ON DUPLICATE KEY UPDATE perm = VALUES(perm)'
        )->execute([$calendarId, $personId, $perm === 'write' ? 'write' : 'read']);
    }

    public static function dropShare(int $calendarId, int $personId): void
    {
        Database::get()->prepare('DELETE FROM calendar_shares WHERE calendar_id = ? AND person_id = ?')
            ->execute([$calendarId, $personId]);
    }

    // ---------------- 日程 ----------------

    public static function addEvent(int $calendarId, array $d): int
    {
        $db = Database::get();
        $db->prepare(
            'INSERT INTO calendar_events
             (calendar_id, title, starts_at, ends_at, start_time, end_time, all_day, note, created_by)
             VALUES (?,?,?,?,?,?,?,?,?)'
        )->execute([
            $calendarId,
            mb_substr(trim((string)$d['title']), 0, 200, 'UTF-8'),
            $d['starts_at'],
            $d['ends_at'] ?: null,
            $d['start_time'] ?: null,
            $d['end_time'] ?: null,
            !empty($d['all_day']) ? 1 : 0,
            self::textOrNull($d['note'] ?? ''),
            $d['created_by'] ?: null,
        ]);
        return (int)$db->lastInsertId();
    }

    public static function updateEvent(int $id, array $d): void
    {
        Database::get()->prepare(
            'UPDATE calendar_events SET title=?, starts_at=?, ends_at=?, start_time=?, end_time=?,
             all_day=?, note=? WHERE id=?'
        )->execute([
            mb_substr(trim((string)$d['title']), 0, 200, 'UTF-8'),
            $d['starts_at'],
            $d['ends_at'] ?: null,
            $d['start_time'] ?: null,
            $d['end_time'] ?: null,
            !empty($d['all_day']) ? 1 : 0,
            self::textOrNull($d['note'] ?? ''),
            $id,
        ]);
    }

    public static function deleteEvent(int $id): void
    {
        Database::get()->prepare('DELETE FROM calendar_events WHERE id = ?')->execute([$id]);
    }

    /**
     * 某个月（或某段日期）里**全部**日程：
     *   自定义日程（calendar_events）+ 观影（events kind=movie）+ 旅行（events kind=trip）
     *   + 有截止时间的任务（tasks.due_at）。
     *
     * 统一成一种形状返回，模板不必分辨来源：
     *   ['cal'=>日历本id, 'color'=>本子颜色, 'title', 'date'=>'Y-m-d', 'time'=>'HH:MM'|'',
     *    'all_day'=>bool, 'kind'=>'custom|movie|trip|task', 'ref_id'=>宿主id, 'href'=>点进去的地址]
     *
     * ⚠️ 观影/旅行只显示**本家庭**的记录（与观影模块同一个口径：能登录就能看）。
     */
    public static function month(int $familyId, array $calendars, int $personId, string $from, string $to): array
    {
        $out = [];
        $byKind = [];
        foreach ($calendars as $c) {
            $byKind[(string)$c['kind']][] = $c;
        }

        // ---- 自定义日程 ----
        $ids = [];
        foreach ($calendars as $c) {
            if ((string)$c['kind'] === 'custom') {
                $ids[] = (int)$c['id'];
            }
        }
        if ($ids) {
            $in  = implode(',', array_fill(0, count($ids), '?'));
            $st  = Database::get()->prepare(
                "SELECT * FROM calendar_events
                  WHERE calendar_id IN ($in) AND starts_at <= ? AND COALESCE(ends_at, starts_at) >= ?
                  ORDER BY starts_at, start_time"
            );
            $st->execute(array_merge($ids, [$to, $from]));
            $calById = [];
            foreach ($calendars as $c) {
                $calById[(int)$c['id']] = $c;
            }
            foreach ($st->fetchAll() as $e) {
                $c   = $calById[(int)$e['calendar_id']] ?? null;
                $end = $e['ends_at'] ?: $e['starts_at'];
                // 跨天日程：在范围内**每天**都出一条（群晖日历就是这么画的）
                foreach (self::eachDay((string)$e['starts_at'], (string)$end, $from, $to) as $day) {
                    $out[] = [
                        'cal'     => (int)$e['calendar_id'],
                        'color'   => (string)($c['color'] ?? '#4A7C82'),
                        'calname' => (string)($c['name'] ?? ''),
                        'title'   => (string)$e['title'],
                        'date'    => $day,
                        'time'    => empty($e['all_day']) ? substr((string)$e['start_time'], 0, 5) : '',
                        'all_day' => !empty($e['all_day']),
                        'kind'    => 'custom',
                        'ref_id'  => (int)$e['id'],
                        'href'    => url('calendar/event', ['id' => (int)$e['id']]),
                    ];
                }
            }
        }

        // ---- 观影（events kind=movie）----
        if (isset($byKind['movie'])) {
            $c = $byKind['movie'][0];
            $st = Database::get()->prepare(
                "SELECT id, title, starts_at, ends_at FROM events
                  WHERE family_id = ? AND kind = 'movie' AND starts_at IS NOT NULL
                    AND DATE(starts_at) BETWEEN ? AND ?
                  ORDER BY starts_at"
            );
            $st->execute([$familyId, $from, $to]);
            foreach ($st->fetchAll() as $e) {
                $day = substr((string)$e['starts_at'], 0, 10);
                $t   = substr((string)$e['starts_at'], 11, 5);
                $out[] = [
                    'cal'     => (int)$c['id'],
                    'color'   => (string)$c['color'],
                    'calname' => (string)$c['name'],
                    'title'   => '🎬 ' . (string)$e['title'],
                    'date'    => $day,
                    'time'    => $t === '00:00' ? '' : $t,
                    'all_day' => $t === '00:00',
                    'kind'    => 'movie',
                    'ref_id'  => (int)$e['id'],
                    'href'    => url('movies/show', ['id' => (int)$e['id']]),
                ];
            }
        }

        // ---- 旅行（events kind=trip）----
        if (isset($byKind['trip'])) {
            $c = $byKind['trip'][0];
            $st = Database::get()->prepare(
                "SELECT id, title, starts_at, ends_at FROM events
                  WHERE family_id = ? AND kind = 'trip' AND starts_at IS NOT NULL
                    AND DATE(starts_at) <= ? AND COALESCE(DATE(ends_at), DATE(starts_at)) >= ?
                  ORDER BY starts_at"
            );
            $st->execute([$familyId, $to, $from]);
            foreach ($st->fetchAll() as $e) {
                foreach (self::eachDay(substr((string)$e['starts_at'], 0, 10),
                                       substr((string)($e['ends_at'] ?: $e['starts_at']), 0, 10),
                                       $from, $to) as $day) {
                    $out[] = [
                        'cal'     => (int)$c['id'],
                        'color'   => (string)$c['color'],
                        'calname' => (string)$c['name'],
                        'title'   => '🧳 ' . (string)$e['title'],
                        'date'    => $day,
                        'time'    => '',
                        'all_day' => true,
                        'kind'    => 'trip',
                        'ref_id'  => (int)$e['id'],
                        'href'    => url('trips/show', ['id' => (int)$e['id']]),
                    ];
                }
            }
        }

        // ---- 有截止时间的任务 ----
        $st = Database::get()->prepare(
            "SELECT t.id, t.title, t.due_at, t.status
               FROM tasks t
               LEFT JOIN task_shares s ON s.task_id = t.id AND s.person_id = ?
              WHERE t.family_id = ? AND t.due_at IS NOT NULL AND t.status <> 'done'
                AND DATE(t.due_at) BETWEEN ? AND ?
                AND (t.creator_id = ? OR t.assignee_id = ? OR s.person_id IS NOT NULL)
              ORDER BY t.due_at"
        );
        $st->execute([$personId, $familyId, $from, $to, $personId, $personId]);
        foreach ($st->fetchAll() as $t) {
            $day = substr((string)$t['due_at'], 0, 10);
            $tm  = substr((string)$t['due_at'], 11, 5);
            $out[] = [
                'cal'     => 0,
                'color'   => '#A8574F',
                'calname' => '任务',
                'title'   => '☑ ' . (string)$t['title'],
                'date'    => $day,
                'time'    => $tm === '00:00' ? '' : $tm,
                'all_day' => $tm === '00:00',
                'kind'    => 'task',
                'ref_id'  => (int)$t['id'],
                'href'    => url('tasks/show', ['id' => (int)$t['id']]),
            ];
        }

        usort($out, static function ($a, $b) {
            return strcmp($a['date'], $b['date'])
                ?: strcmp((string)$a['time'], (string)$b['time'])
                ?: strcmp($a['title'], $b['title']);
        });
        return $out;
    }

    /** 把 [start, end] 夹到 [from, to] 里，逐天列出（含端点） */
    private static function eachDay(string $start, string $end, string $from, string $to): array
    {
        $s = max($start, $from);
        $e = min($end, $to);
        if ($s > $e) {
            return [];
        }
        $out = [];
        $cur = $s;
        for ($i = 0; $i < 400 && $cur <= $e; $i++) {
            $out[] = $cur;
            $cur   = date('Y-m-d', strtotime($cur . ' +1 day'));
        }
        return $out;
    }

    private static function nextPosition(int $ownerId): int
    {
        $st = Database::get()->prepare('SELECT COALESCE(MAX(position),0)+10 FROM calendars WHERE owner_id = ?');
        $st->execute([$ownerId]);
        return (int)$st->fetchColumn();
    }

    private static function textOrNull(string $v): ?string
    {
        $v = trim($v);
        return $v !== '' ? $v : null;
    }
}