import { PinyinBaseDraw } from '../../shared/pinyinBaseDraw';
import {
    generatePinyinDaily,
    type PinyinDailySection,
} from '../../shared/pinyinDailyGenerator';
import { TONEOZ_PINYIN, fontFamilyOf } from '../../../core/font/fontProfiles';
import { loadFontFace } from '../../../core/font/fontLoader';
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';

const PAGE_MARGIN = 14;
const SECTION_PADDING_X = 18;

const GRID_COL_GAP = 6;
const GRID_ROW_GAP = 8;

export default class PinyinDailyDraw extends PinyinBaseDraw {
    async draw(dayIndex: number) {
        const dailyData = generatePinyinDaily(dayIndex);

        this.prepareDraw();
        await loadFontFace(TONEOZ_PINYIN);

        this.drawPageDividers();

        const sectionRects = this.getSectionRects();
        for (let i = 0; i < sectionRects.length; i++) {
            const section = dailyData.sections[i];
            if (section) {
                this.drawSection(sectionRects[i], section, i + 1);
            }
        }
    }

    private drawPageDividers() {
        const cx = this.canvasWidth / 2;
        const cy = this.canvasHeight / 2;
        const dashStyle = {
            isDashed: true,
            dashPattern: [5, 5],
            color: '#D6D2CC',
            lineWidth: 1,
        };

        this.drawLine(
            cx,
            PAGE_MARGIN,
            cx,
            this.canvasHeight - PAGE_MARGIN,
            dashStyle,
        );
        this.drawLine(
            PAGE_MARGIN,
            cy,
            this.canvasWidth - PAGE_MARGIN,
            cy,
            dashStyle,
        );
    }

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

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

    private drawSection(
        rect: { x: number; y: number; w: number; h: number },
        section: PinyinDailySection,
        sectionIndex: number,
    ) {
        const phrase = getRandomEncouragementPhrase();
        drawSectionHeader(this.ctx, rect, '拼音每日打卡');
        this.drawSectionGrid(rect, section);
        drawSectionFooter(this.ctx, rect, phrase, `- ${sectionIndex} -`);
    }

    private drawSectionGrid(
        rect: { x: number; y: number; w: number; h: number },
        section: PinyinDailySection,
    ) {
        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 cols = section.cols;
        const rows = section.rows;
        const cellW = (contentWidth - GRID_COL_GAP * (cols - 1)) / cols;
        const cellH =
            (contentHeight - GRID_ROW_GAP * (rows.length - 1)) / rows.length;
        const fontFamily = fontFamilyOf(TONEOZ_PINYIN);

        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 < cols; colIdx++) {
                const cell = row.cells[colIdx];
                const x =
                    rect.x +
                    SECTION_PADDING_X +
                    colIdx * (cellW + GRID_COL_GAP);

                this.drawFourLineGrid(x, y, cellW, cellH);

                if (cell) {
                    const cx = x + cellW / 2;
                    const fontSize = Math.round(cellH * 0.7);
                    const baselineY = y + (cellH * 2) / 3;

                    let charToDraw = cell.char;
                    const variants = section.task.variants || [];
                    const hasVariants = variants.length > 0;

                    if (cols === 5) {
                        if (hasVariants) {
                            if (colIdx === 0) {
                                charToDraw = section.task.char;
                            } else {
                                charToDraw =
                                    variants[colIdx - 1] || section.task.char;
                            }
                        } else {
                            charToDraw = section.task.char;
                        }
                    } else if (cols === 4) {
                        let drawnRowIdx = -1;
                        if (rowIdx === 0) drawnRowIdx = 0;
                        else if (rowIdx === 1) drawnRowIdx = 1;
                        else if (rowIdx === 3) drawnRowIdx = 2;
                        else if (rowIdx === 5) drawnRowIdx = 3;

                        if (drawnRowIdx !== -1 && hasVariants) {
                            charToDraw =
                                variants[drawnRowIdx] || section.task.char;
                        } else {
                            charToDraw = section.task.char;
                        }
                    }

                    this.ctx.save();
                    this.ctx.font = `${fontSize}px ${fontFamily}`;
                    this.ctx.fillStyle = cell.color;
                    this.ctx.globalAlpha = cell.alpha;
                    this.ctx.textAlign = 'center';
                    this.ctx.textBaseline = 'alphabetic';
                    this.ctx.fillText(charToDraw, cx, baselineY);
                    this.ctx.restore();
                }
            }
        }
    }
}