import DotConnectDraw from '../shared/service/dotConnectDraw';
import { createFocusPage } from '../shared/common/focusPageMixin';
import { DotConnectData } from '../shared/service/dotConnectDraw';
import { getRandomUniqueNumberColors } from '../../constants/colors';

createFocusPage({
    canvas: null as Canvas | null,
    ctx: null as RenderingContext | null,
    boxHeight: 0,
    boxWidth: 0,
    drawService: null as DotConnectDraw | null,
    dotConnectData: null as DotConnectData | null,

    data: {
        pageTitle: '数字点连线',
        functionId: '',
        hasContent: false,
        showShareDialog: false,
    },

    onLoad(options: { id?: string }) {
        const functionId = options.id || 'dot-connect';
        this.setData({
            functionId,
        });
        this.initPageInfo(functionId, '数字点连线');
    },

    onReady() {
        this.initCanvas({
            createDrawService: (
                canvas: Canvas,
                ctx: RenderingContext,
                options?: Record<string, any>,
            ) => {
                return new DotConnectDraw(canvas, ctx, options);
            },
            drawServiceOptions: {
                title: this.data.pageTitle,
                functionId: this.data.functionId,
            },
            onCanvasReady: () => {
                // 初始随机生成
                this.onRandom();
            },
        });
    },

    /**
     * 绘制Canvas内容
     */
    async drawCanvas() {
        if (!this.ctx || !this.drawService || !this.dotConnectData) {
            return;
        }

        try {
            await this.drawService.draw(this.dotConnectData);
            this.setData({ hasContent: true });
        } catch (error) {
            console.error('绘制失败:', error);
            this.setData({ hasContent: false });
        }
    },

    /**
     * 生成不走回头路的数字序列
     * @param length 序列长度
     * @returns 数字序列数组
     */
    generateNonBacktrackingSequence(length: number): number[] {
        // 3x3 网格中数字的位置映射
        // 1: (0,0), 2: (1,0), 3: (2,0)
        // 4: (0,1), 5: (1,1), 6: (2,1)
        // 7: (0,2), 8: (1,2), 9: (2,2)
        const getPosition = (num: number): [number, number] => {
            const row = Math.floor((num - 1) / 3);
            const col = (num - 1) % 3;
            return [row, col];
        };

        // 检查从位置A到位置B再到位置C是否走回头路
        const isBacktrack = (
            posA: [number, number],
            posB: [number, number],
            posC: [number, number],
        ): boolean => {
            // 如果C等于A，说明走回头路了
            return posC[0] === posA[0] && posC[1] === posA[1];
        };

        const sequence: number[] = [];
        const used = new Set<number>();

        // 随机选择起始数字
        const startNum = Math.floor(Math.random() * 9) + 1;
        sequence.push(startNum);
        used.add(startNum);

        let prevPos = getPosition(startNum);
        let prevPrevPos: [number, number] | null = null;

        // 生成剩余的数字
        while (sequence.length < length) {
            const candidates: number[] = [];
            for (let num = 1; num <= 9; num++) {
                if (used.has(num)) continue;

                const currentPos = getPosition(num);
                // 如果有前前一个位置，检查是否走回头路
                if (prevPrevPos) {
                    if (isBacktrack(prevPrevPos, prevPos, currentPos)) {
                        continue;
                    }
                }
                candidates.push(num);
            }

            if (candidates.length === 0) {
                // 如果没有候选数字，随机选择一个未使用的数字
                const remaining = Array.from(
                    { length: 9 },
                    (_, i) => i + 1,
                ).filter((n) => !used.has(n));
                if (remaining.length === 0) break;
                const nextNum =
                    remaining[Math.floor(Math.random() * remaining.length)];
                sequence.push(nextNum);
                used.add(nextNum);
                prevPrevPos = prevPos;
                prevPos = getPosition(nextNum);
            } else {
                // 随机选择一个候选数字
                const nextNum =
                    candidates[Math.floor(Math.random() * candidates.length)];
                sequence.push(nextNum);
                used.add(nextNum);
                prevPrevPos = prevPos;
                prevPos = getPosition(nextNum);
            }
        }

        return sequence;
    },

    /**
     * 随机生成
     */
    onRandom() {
        // 生成1-9的数字颜色映射（每个数字使用随机颜色）
        const numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9];
        const colors = getRandomUniqueNumberColors(9);
        const colorMap = numbers.map((number, index) => ({
            number,
            color: colors[index],
        }));

        // 生成9个组的题目
        const groups: Array<{
            sequence: number[];
        }> = [];

        for (let i = 0; i < 9; i++) {
            // 生成不走回头路的数字序列，长度在4-6之间
            const sequenceLength = Math.floor(Math.random() * 3) + 4; // 4, 5, 或 6
            const sequence =
                this.generateNonBacktrackingSequence(sequenceLength);
            groups.push({
                sequence,
            });
        }

        this.dotConnectData = {
            colorMap,
            groups,
        };

        this.drawCanvas();
    },
});