click-captcha
Version:
Chinese Character Sequence Click Verification System
140 lines (139 loc) • 5.88 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.ClickCaptcha = void 0;
const utils_1 = require("../utils");
const svg_builder_1 = require("./svg-builder");
const sharp = require("sharp");
const options_1 = require("../const/options");
class ClickCaptcha {
constructor(options) {
this.options = (0, utils_1.deepMerge)(options_1.DEFAULT_OPTIONS, options || {});
this.validateOptions();
}
validateOptions() {
const { characters } = this.options;
if (!characters.pool || characters.pool.length < 10) {
throw new Error("至少需要提供 10 个字符");
}
if (characters.pool.length < characters.count) {
throw new Error("字符集长度小于生成的字符数量");
}
}
/**
* 生成随机位置
*/
getRandomPosition(existingPositions = []) {
const { dimensions, font, characters, security } = this.options;
const minDistance = font.fontSize * characters.minSpacing;
let attempts = 0;
while (attempts < security.positionGenerationAttempts) {
const x = dimensions.padding +
Math.random() * (dimensions.width - 2 * dimensions.padding);
const y = dimensions.padding +
Math.random() * (dimensions.height - 2 * dimensions.padding);
// 碰撞检测
const isOverlap = existingPositions.some((pos) => {
const dx = pos.x - x;
const dy = pos.y - y;
return Math.sqrt(dx * dx + dy * dy) < minDistance;
});
if (!isOverlap) {
return { x, y };
}
attempts++;
}
// 超过尝试次数则返回随机位置
return {
x: dimensions.padding +
Math.random() * (dimensions.width - 2 * dimensions.padding),
y: dimensions.padding +
Math.random() * (dimensions.height - 2 * dimensions.padding),
};
}
/**
* 生成随机字符
*/
getRandomChar(existingChars) {
const { characters } = this.options;
const allChars = characters.pool.split("");
const filteredChars = allChars.filter((char) => !existingChars.includes(char));
return filteredChars[utils_1.Random.int(0, filteredChars.length)];
}
/**
* @author Qing
* @description 生成点击验证码
* @return {Promise<CaptchaResult>} 验证码结果
* @example
* const captcha = new ClickCaptcha();
* const { image, hint, data } = await captcha.generate();
* @date 2025-02-14 10:21:01
*/
async generate() {
const { characters } = this.options;
try {
// 生成随机字符和位置
const existingPositions = [];
const chars = [];
Array.from({ length: characters.count }, () => {
const char = this.getRandomChar(chars.map((c) => c.char));
const pos = this.getRandomPosition(existingPositions);
existingPositions.push(pos);
chars.push({ char, coordinates: pos });
});
// 生成主图片并转换为base64
const mainSvg = svg_builder_1.SvgBuilder.buildMain(chars, this.options);
const mainBuffer = await sharp(Buffer.from(mainSvg)).png().toBuffer();
const mainBase64 = `data:image/png;base64,${mainBuffer.toString("base64")}`;
// 生成提示图片并转换为base64
const hintSvg = svg_builder_1.SvgBuilder.buildHint(chars, this.options);
const hintBuffer = await sharp(Buffer.from(hintSvg)).png().toBuffer();
const hintBase64 = `data:image/png;base64,${hintBuffer.toString("base64")}`;
return {
imageBase64: mainBase64,
hintBase64: hintBase64,
verificationPoints: chars,
};
}
catch (error) {
throw new Error(`验证码生成失败: ${error}`);
}
}
/**
* @author Qing
* @description 验证点击位置
* @param {Coordinate[]} userPositions 用户点击位置
* @param {VerificationPoint[]} verificationPoints 数据中的正确的验证码字符位置
* @return {boolean} 是否验证通过
* @date 2025-02-14 10:20:16
*/
verify(userPositions, verificationPoints) {
const { security, dimensions } = this.options;
const tolerance = security.clickTolerance;
if (userPositions.length !== verificationPoints.length) {
return false;
}
console.info(new Date().toLocaleString(), "用户点击位置：", userPositions.map((p) => ({
x: p.x * dimensions.width,
y: p.y * dimensions.height,
})), "验证码字符位置：", verificationPoints.map((p) => ({
x: p.coordinates.x,
y: p.coordinates.y,
})), "正确信息：", verificationPoints.map((p) => ({
x: p.coordinates.x / dimensions.width,
y: p.coordinates.y / dimensions.height,
})));
return userPositions.every((pos, index) => {
const char = verificationPoints[index].coordinates;
// 将百分比转换为原始坐标系的绝对位置
const clickX = pos.x * dimensions.width;
const clickY = pos.y * dimensions.height;
const distance = Math.sqrt(Math.pow(clickX - char.x, 2) + Math.pow(clickY - char.y, 2));
const res = distance <= tolerance;
if (!res) {
console.info(`第${index + 1}个字符点击位置错误，正确位置：${char.x},${char.y}，点击位置：${clickX},${clickY}，距离：${distance}`);
}
return res;
});
}
}
exports.ClickCaptcha = ClickCaptcha;