<?php

namespace app\api\logic\tcm;

/**
 * 霍大夫升糖指数（GI）知识库
 */
class GiKnowledge
{
    public const LEVEL_LOW = 'low';
    public const LEVEL_MEDIUM = 'medium';
    public const LEVEL_HIGH = 'high';

    /** @var array<string, array<string, list<string>>> */
    private static array $foods = [
        self::LEVEL_LOW => [
            '五谷类' => ['全蛋面', '荞麦面', '粉丝', '黑米', '黑米粥', '通心粉', '藕粉'],
            '蔬菜类' => ['魔芋', '粟米', '大白菜', '黄瓜', '芹菜', '茄子', '青椒', '海带', '金针菇', '香菇', '菠菜', '番茄', '豆芽', '芦笋', '花椰菜', '洋葱', '生菜'],
            '豆类'   => ['黄豆', '眉豆', '鸡心豆', '豆腐', '豆角', '绿豆', '扁豆', '四季豆'],
            '水果类' => ['苹果', '水梨', '橙子', '桃', '提子', '沙田柚', '雪梨', '车厘子', '柚子', '草莓', '樱桃', '金桔', '葡萄'],
            '奶类'   => ['牛奶', '低脂奶', '脱脂奶', '低脂乳酪', '红茶', '优格', '无糖豆浆'],
        ],
        self::LEVEL_MEDIUM => [
            '主食类' => ['红米饭', '糙米饭', '西米', '乌冬面', '面包', '麦片', '番薯', '芋头'],
            '蔬菜类' => ['薯片', '番茄', '莲藕', '牛蒡'],
            '肉类'   => ['鱼肉', '鸡肉', '鸭肉', '猪肉', '羊肉', '牛肉', '虾子', '蟹'],
            '水果类' => ['木瓜', '提子干', '菠萝', '香蕉', '芒果', '哈密瓜', '奇异果', '柳丁'],
            '其他'   => ['蔗糖', '蜂蜜', '红酒', '啤酒', '可乐', '咖啡'],
        ],
        self::LEVEL_HIGH => [
            '主食类'     => ['白饭', '馒头', '油条', '糯米饭', '白面包', '燕麦片', '拉面', '炒饭', '爆米花'],
            '肉类加工品' => ['贡丸', '肥肠', '蛋饺'],
            '蔬菜类'     => ['薯蓉', '南瓜', '焗薯'],
            '水果类'     => ['西瓜', '荔枝', '龙眼', '凤梨', '枣'],
            '其他'       => ['葡萄糖', '砂糖', '麦芽糖', '汽水', '柳橙汁', '蜂蜜'],
        ],
    ];

    /** @var list<array{breakfast:string,lunch:string,dinner:string,tips:string}> */
    private static array $mealTemplates = [
        [
            'breakfast' => '玉米碴子粥、煮鸡蛋、拌黄瓜',
            'lunch'     => '清炖鲤鱼、豆腐炖白菜、清炒豆角、米饭小半碗',
            'dinner'    => '玉米面饼一个、瘦肉丝、凉拌茄子',
            'tips'      => '中午鱼豆肉吃足；早中晚淀粉别重复，一顿一种主食就够。',
        ],
        [
            'breakfast' => '小米粥、煮鸡蛋、小碟咸菜（少盐）',
            'lunch'     => '去皮炖鸡肉、芹菜炒豆干、木耳炒鸡蛋',
            'dinner'    => '蒸红薯（小半块）、清炒菠菜、豆腐汤',
            'tips'      => '午餐最讲究蛋白；晚上才吃薯，别跟中午再配大米饭。',
        ],
        [
            'breakfast' => '豆腐脑（少卤）、鸡蛋、一个苹果',
            'lunch'     => '清炖鸡肉、炖芸豆、番茄炒蛋、贴饼子一个',
            'dinner'    => '挂面一小碗、清蒸小鱼、拌海带丝',
            'tips'      => '中午饼配肉豆，蛋白管够；面条放晚上，别三顿都是粥饭。',
        ],
        [
            'breakfast' => '高粱米粥、茶叶蛋、拌萝卜丝',
            'lunch'     => '炖牛肉（瘦）、豆腐炒韭菜、清炒油菜、杂豆饭小半碗',
            'dinner'    => '蒸南瓜（小半碗）、鸡蛋羹、拍黄瓜',
            'tips'      => '中午肉蛋豆要多吃；南瓜算晚饭主食，别再加馒头稀饭。',
        ],
        [
            'breakfast' => '棒子面粥、水煮蛋、大拌菜（少油）',
            'lunch'     => '清炖鲫鱼、番茄炒蛋、炖扁豆、糙米饭小半碗',
            'dinner'    => '玉米面饼一个、清炒豆芽、豆腐脑',
            'tips'      => '午饭鱼蛋豆齐上；玉米面放晚上，跟中午米饭分开。',
        ],
        [
            'breakfast' => '小米粥、煮鸡蛋、拌生菜',
            'lunch'     => '白切鸡（去皮）、炖豆腐、清炒豆角、二米饭小半碗',
            'dinner'    => '杂面馒头一个、瘦肉炒芹菜、凉拌黄瓜',
            'tips'      => '中午蛋白打主力；三顿别都喝粥吃面，一顿一种淀粉。',
        ],
    ];

    public static function summaryText(): string
    {
        $path = root_path() . 'app/api/logic/tcm/data/gi_huo_summary.txt';
        if (is_file($path)) {
            $text = trim((string) file_get_contents($path));
            if ($text !== '') {
                return $text;
            }
        }
        return '低 GI（≤55）优先；中 GI（56-69）适量；高 GI（≥70）尽量避免。多选全谷物、蔬菜、豆类，少加工、少精制糖。';
    }

    /** 农村/口语别名 → 标准名（便于「能不能吃」匹配） */
    private static array $aliases = [
        '棒子面' => '荞麦面', '玉米碴' => '粟米', '地瓜' => '番薯', '红薯' => '番薯',
        '洋芋' => '芋头', '土豆' => '芋头', '窝头' => '通心粉', '贴饼子' => '通心粉',
        '二米饭' => '红米饭', '稀饭' => '白饭', '白稀饭' => '白饭', '糖糕' => '麦芽糖',
    ];

    /**
     * @return array{level:string,level_label:string,category:string,advice:string}|null
     */
    public static function lookupFood(string $name): ?array
    {
        $name = trim($name);
        if ($name === '') {
            return null;
        }

        $canonical = self::$aliases[$name] ?? $name;

        foreach ([self::LEVEL_LOW, self::LEVEL_MEDIUM, self::LEVEL_HIGH] as $level) {
            foreach (self::$foods[$level] as $category => $items) {
                foreach ($items as $item) {
                    if ($canonical === $item || $name === $item
                        || mb_strpos($item, $canonical) !== false || mb_strpos($canonical, $item) !== false
                        || mb_strpos($item, $name) !== false || mb_strpos($name, $item) !== false) {
                        return [
                            'level'       => $level,
                            'level_label' => self::levelLabel($level),
                            'category'    => $category,
                            'food'        => $item,
                            'advice'      => self::adviceForLevel($level, $name),
                        ];
                    }
                }
            }
        }

        return null;
    }

    /** 供 AI 参考：老农民家常、集市易得食材示例 */
    public static function ruralMealHints(): string
    {
        return implode("\n", [
            '【午餐】蛋白质要最高：至少 2 样高蛋白（鱼/鸡鸭/瘦肉/蛋/豆腐/豆干），肉蛋豆是午饭主角。',
            '【淀粉不重复】粥/饭/面/饼/窝头/红薯/土豆/玉米/南瓜等算淀粉；早中晚各最多 1 种，且三顿不能同一种、不要顿顿大主食。',
            '推荐蛋白：鸡蛋、豆腐、豆干、自家鸡鸭蛋、瘦肉、鲫鱼鲤鱼；',
            '推荐蔬菜：白菜、萝卜、黄瓜、豆角、茄子、菠菜、芹菜；',
            '淀粉示例（全天选 3 种不同的）：玉米碴粥、二米饭小半碗、贴饼子、杂面窝头、挂面小碗、蒸红薯；',
            '少吃：白馒头、油条、粘豆包、糯米饭、西瓜、含糖饮料、糕点。',
            '说话要土话、短句，像村里大夫叮嘱。',
        ]);
    }

    public static function levelLabel(string $level): string
    {
        return match ($level) {
            self::LEVEL_LOW    => '低升糖',
            self::LEVEL_MEDIUM => '中升糖',
            default            => '高升糖',
        };
    }

    public static function adviceForLevel(string $level, string $food): string
    {
        return match ($level) {
            self::LEVEL_LOW => "「{$food}」升糖慢，老农民家常能吃，当菜当饭都行，有助于稳血糖。",
            self::LEVEL_MEDIUM => "「{$food}」升糖中等，可以吃但要少搁点，别当主食猛吃，配着蔬菜鸡蛋更好。",
            default => "「{$food}」升糖快，血糖高时尽量别吃或少吃，尤其别空腹猛吃。",
        };
    }

    /**
     * @param int|null $templateIndex 指定模板下标（换一换时轮换）
     * @return array{breakfast:string,lunch:string,dinner:string,tips:string,avoid:list<string>,source:string}
     */
    public static function fallbackDailyMeals(int $diagnosisId, ?int $templateIndex = null): array
    {
        $templates = self::$mealTemplates;
        $count     = count($templates);
        if ($templateIndex !== null) {
            $idx = (($templateIndex % $count) + $count) % $count;
        } else {
            $idx = abs(crc32(date('Y-m-d') . ':' . $diagnosisId)) % $count;
        }
        $meal = $templates[$idx];

        $plan = [
            'breakfast' => $meal['breakfast'],
            'lunch'     => $meal['lunch'],
            'dinner'    => $meal['dinner'],
            'tips'      => $meal['tips'],
            'avoid'     => ['白面馒头', '油条', '粘豆包', '西瓜', '含糖饮料', '稀饭配糖'],
            'source'    => 'rule',
        ];

        $checked = DietMealValidator::validateAndNormalize($plan);
        $out     = $checked['plan'];
        $out['source'] = 'rule';
        $out['rules_summary'] = DietMealValidator::metaSummary($checked['meta']);

        return $out;
    }

    /**
     * @return array{food:string,level:string,level_label:string,advice:string,source:string}
     */
    public static function fallbackAsk(string $question): array
    {
        $food = self::extractFoodName($question);
        $hit  = self::lookupFood($food);

        if ($hit) {
            return [
                'food'        => $hit['food'],
                'level'       => $hit['level'],
                'level_label' => $hit['level_label'],
                'advice'      => $hit['advice'],
                'source'      => 'rule',
            ];
        }

        return [
            'food'        => $food,
            'level'       => '',
            'level_label' => '未知',
            'advice'      => '库里没查到「' . $food . '」。一般多吃小米玉米、白菜豆角豆腐鸡蛋，少吃白馒头油条甜口；拿不准问村医。',
            'source'      => 'rule',
        ];
    }

    public static function extractFoodName(string $question): string
    {
        $q = trim($question);
        $q = preg_replace('/^(能不能吃|可以吃|能吃|可不可以吃|请问|我想问)/u', '', $q) ?? $q;
        $q = preg_replace('/(吗|呢|？|\?)+$/u', '', $q) ?? $q;
        $q = trim($q);
        return $q !== '' ? $q : $question;
    }
}