import { BaseDrawService } from '../../../core/draw/baseDraw';
import type {
    DailyCheckinRow,
    DailyCheckinSection,
    LetterTracingData,
} from '../generators/letter-tracing-generator';
import {
    PRINT_CLEARLY_DASHED,
    PRINT_CLEARLY_REGULAR,
    fontFamilyOf,
} from '../../../core/font/fontProfiles';
import {
    calcLetterFontSizes,
    drawClosedFourLineGrid,
    drawLetterInFourLineGrid,
    loadLetterFont,
} from '../../shared/draw/drawTools';
import {
    SECTION_PADDING_TOP,
    SECTION_PADDING_BOTTOM,
    HEADER_TITLE_GAP,
    HEADER_META_GAP,
    CONTENT_TOP_GAP,
    FOOTER_PHRASE_GAP,
    FOOTER_INDEX_GAP,
    drawSectionHeader,
    drawSectionFooter,
    getRandomEncouragementPhrase,
} from '../../../core/draw/dailyPracticeDrawHelper';

type DailyCheckinData = Extract<
    LetterTracingData,
    { mode: 'letter-tracing-daily-checkin' }
>;

// 页面左右边距（px）
const PAGE_MARGIN_X = 14;
// 页面上下边距（px）
const PAGE_MARGIN_Y = 14;
// 每个分区内容区左右内边距（px）
const SECTION_PADDING_X = 18;

// 单个格子区列数
const GRID_COLS = 5;
// 单个格子区行数
const GRID_ROWS = 7;
// 格子列间距（px）
const GRID_COL_GAP = 6;
// 格子行间距（px）
const GRID_ROW_GAP = 8;

import { GRID_COLORS, TRACING_COLORS } from '../../../core/data/tracingStyles';

const GRID_BORDER = GRID_COLORS.border;
const GRID_MIDDLE = GRID_COLORS.middleLine;

const COLOR_BLACK = TRACING_COLORS.strong;
const COLOR_LIGHT_RED = TRACING_COLORS.guide;

export default class DailyCheckinDraw extends BaseDrawService {
    async draw(data: DailyCheckinData) {
        this.prepareDraw();
        await Promise.all([
            loadLetterFont(PRINT_CLEARLY_REGULAR),
            loadLetterFont(PRINT_CLEARLY_DASHED),
        ]);

        this.drawPageDividers();

        const sections = this.getSectionRects();
        for (let i = 0; i < sections.length; i++) {
            this.drawSection(sections[i], data.sections[i] ?? null);
        }
    }

    private drawPageDividers() {
        const verticalX = this.canvasWidth / 2;
        const horizontalY = this.canvasHeight / 2;

        this.drawLine(
            verticalX,
            PAGE_MARGIN_Y,
            verticalX,
            this.canvasHeight - PAGE_MARGIN_Y,
            {
                isDashed: true,
                dashPattern: [5, 5],
                color: '#D6D2CC',
                lineWidth: 1,
            },
        );

        this.drawLine(
            PAGE_MARGIN_X,
            horizontalY,
            this.canvasWidth - PAGE_MARGIN_X,
            horizontalY,
            {
                isDashed: true,
                dashPattern: [5, 5],
                color: '#D6D2CC',
                lineWidth: 1,
            },
        );
    }

    private getSectionRects() {
        const halfW = this.canvasWidth / 2;
        const halfH = this.canvasHeight / 2;

        return [
            {
                x: PAGE_MARGIN_X,
                y: PAGE_MARGIN_Y,
                w: halfW - PAGE_MARGIN_X,
                h: halfH - PAGE_MARGIN_Y,
            },
            {
                x: halfW,
                y: PAGE_MARGIN_Y,
                w: this.canvasWidth - PAGE_MARGIN_X - halfW,
                h: halfH - PAGE_MARGIN_Y,
            },
            {
                x: PAGE_MARGIN_X,
                y: halfH,
                w: halfW - PAGE_MARGIN_X,
                h: this.canvasHeight - PAGE_MARGIN_Y - halfH,
            },
            {
                x: halfW,
                y: halfH,
                w: this.canvasWidth - PAGE_MARGIN_X - halfW,
                h: this.canvasHeight - PAGE_MARGIN_Y - halfH,
            },
        ];
    }

    private drawSection(
        rect: { x: number; y: number; w: number; h: number },
        section: DailyCheckinSection | null,
    ) {
        if (!section) return;

        const phrase = getRandomEncouragementPhrase();
        drawSectionHeader(this.ctx, rect, '字母每日打卡');
        drawSectionFooter(this.ctx, rect, phrase, `- ${section.pageNumber} -`);
        this.drawSectionGrid(rect, section.rows);
    }

    private drawSectionGrid(
        rect: { x: number; y: number; w: number; h: number },
        rows: DailyCheckinRow[],
    ) {
        const contentTop =
            rect.y +
            SECTION_PADDING_TOP +
            HEADER_TITLE_GAP +
            HEADER_META_GAP +
            CONTENT_TOP_GAP;
        const contentBottom =
            rect.y +
            rect.h -
            SECTION_PADDING_BOTTOM -
            FOOTER_PHRASE_GAP -
            FOOTER_INDEX_GAP;
        const contentHeight = contentBottom - contentTop;
        const contentWidth = rect.w - SECTION_PADDING_X * 2;

        const cellW =
            (contentWidth - GRID_COL_GAP * (GRID_COLS - 1)) / GRID_COLS;
        const cellH =
            (contentHeight - GRID_ROW_GAP * (GRID_ROWS - 1)) / GRID_ROWS;
        const pairGap = 16;
        const regularSizes = calcLetterFontSizes(
            cellH * 0.98,
            PRINT_CLEARLY_REGULAR,
        );
        const dashedSizes = calcLetterFontSizes(
            cellH * 0.98,
            PRINT_CLEARLY_DASHED,
        );

        for (let rowIdx = 0; rowIdx < rows.length; rowIdx++) {
            const row = rows[rowIdx];
            const y = contentTop + rowIdx * (cellH + GRID_ROW_GAP);

            for (let colIdx = 0; colIdx < GRID_COLS; colIdx++) {
                const x =
                    rect.x +
                    SECTION_PADDING_X +
                    colIdx * (cellW + GRID_COL_GAP);
                drawClosedFourLineGrid(this.ctx, x, y, cellW, cellH, {
                    ink: GRID_BORDER,
                    middleInk: GRID_MIDDLE,
                    lineWidth: 1,
                    dash: [3, 3],
                });

                const cell = row.cells[colIdx];
                if (!cell) continue;

                const sizes =
                    row.style === 'dashed' ? dashedSizes : regularSizes;
                const fontFamily = fontFamilyOf(
                    row.style === 'dashed'
                        ? PRINT_CLEARLY_DASHED
                        : PRINT_CLEARLY_REGULAR,
                );
                const centerX = x + cellW / 2;

                this.ctx.save();
                this.ctx.globalAlpha = cell.alpha;

                drawLetterInFourLineGrid(
                    this.ctx,
                    cell.upper,
                    centerX - pairGap / 2,
                    y,
                    cellH,
                    sizes,
                    {
                        fontFamily,
                        color:
                            cell.color === COLOR_BLACK
                                ? COLOR_BLACK
                                : COLOR_LIGHT_RED,
                    },
                );

                drawLetterInFourLineGrid(
                    this.ctx,
                    cell.lower,
                    centerX + pairGap / 2,
                    y,
                    cellH,
                    sizes,
                    {
                        fontFamily,
                        color:
                            cell.color === COLOR_BLACK
                                ? COLOR_BLACK
                                : COLOR_LIGHT_RED,
                    },
                );

                this.ctx.restore();
            }
        }
    }
}