1 files changed, 267 insertions, 0 deletions
diff --git a/src/client/scripts/aiscript/evaluator.ts b/src/client/scripts/aiscript/evaluator.ts
new file mode 100644
index 0000000000..cc1adf4499
--- /dev/null
+++ b/src/client/scripts/aiscript/evaluator.ts
@@ -0,0 +1,267 @@
+import autobind from 'autobind-decorator';
+import * as seedrandom from 'seedrandom';
+import { Variable, PageVar, envVarsDef, funcDefs, Block, isFnBlock } from '.';
+import { version } from '../../config';
+
+type Fn = {
+	slots: string[];
+	exec: (args: Record<string, any>) => ReturnType<ASEvaluator['evaluate']>;
+};
+
+/**
+ * AiScript evaluator
+ */
+export class ASEvaluator {
+	private variables: Variable[];
+	private pageVars: PageVar[];
+	private envVars: Record<keyof typeof envVarsDef, any>;
+
+	private opts: {
+		randomSeed: string; user?: any; visitor?: any; page?: any; url?: string;
+	};
+
+	constructor(variables: Variable[], pageVars: PageVar[], opts: ASEvaluator['opts']) {
+		this.variables = variables;
+		this.pageVars = pageVars;
+		this.opts = opts;
+
+		const date = new Date();
+
+		this.envVars = {
+			AI: 'kawaii',
+			VERSION: version,
+			URL: opts.page ? `${opts.url}/@${opts.page.user.username}/pages/${opts.page.name}` : '',
+			LOGIN: opts.visitor != null,
+			NAME: opts.visitor ? opts.visitor.name || opts.visitor.username : '',
+			USERNAME: opts.visitor ? opts.visitor.username : '',
+			USERID: opts.visitor ? opts.visitor.id : '',
+			NOTES_COUNT: opts.visitor ? opts.visitor.notesCount : 0,
+			FOLLOWERS_COUNT: opts.visitor ? opts.visitor.followersCount : 0,
+			FOLLOWING_COUNT: opts.visitor ? opts.visitor.followingCount : 0,
+			IS_CAT: opts.visitor ? opts.visitor.isCat : false,
+			MY_NOTES_COUNT: opts.user ? opts.user.notesCount : 0,
+			MY_FOLLOWERS_COUNT: opts.user ? opts.user.followersCount : 0,
+			MY_FOLLOWING_COUNT: opts.user ? opts.user.followingCount : 0,
+			SEED: opts.randomSeed ? opts.randomSeed : '',
+			YMD: `${date.getFullYear()}/${date.getMonth() + 1}/${date.getDate()}`,
+			NULL: null
+		};
+	}
+
+	@autobind
+	public updatePageVar(name: string, value: any) {
+		const pageVar = this.pageVars.find(v => v.name === name);
+		if (pageVar !== undefined) {
+			pageVar.value = value;
+		} else {
+			throw new AiScriptError(`No such page var '${name}'`);
+		}
+	}
+
+	@autobind
+	public updateRandomSeed(seed: string) {
+		this.opts.randomSeed = seed;
+		this.envVars.SEED = seed;
+	}
+
+	@autobind
+	private interpolate(str: string, scope: Scope) {
+		return str.replace(/{(.+?)}/g, match => {
+			const v = scope.getState(match.slice(1, -1).trim());
+			return v == null ? 'NULL' : v.toString();
+		});
+	}
+
+	@autobind
+	public evaluateVars(): Record<string, any> {
+		const values: Record<string, any> = {};
+
+		for (const [k, v] of Object.entries(this.envVars)) {
+			values[k] = v;
+		}
+
+		for (const v of this.pageVars) {
+			values[v.name] = v.value;
+		}
+
+		for (const v of this.variables) {
+			values[v.name] = this.evaluate(v, new Scope([values]));
+		}
+
+		return values;
+	}
+
+	@autobind
+	private evaluate(block: Block, scope: Scope): any {
+		if (block.type === null) {
+			return null;
+		}
+
+		if (block.type === 'number') {
+			return parseInt(block.value, 10);
+		}
+
+		if (block.type === 'text' || block.type === 'multiLineText') {
+			return this.interpolate(block.value || '', scope);
+		}
+
+		if (block.type === 'textList') {
+			return this.interpolate(block.value || '', scope).trim().split('\n');
+		}
+
+		if (block.type === 'ref') {
+			return scope.getState(block.value);
+		}
+
+		if (isFnBlock(block)) { // ユーザー関数定義
+			return {
+				slots: block.value.slots.map(x => x.name),
+				exec: (slotArg: Record<string, any>) => {
+					return this.evaluate(block.value.expression, scope.createChildScope(slotArg, block.id));
+				}
+			} as Fn;
+		}
+
+		if (block.type.startsWith('fn:')) { // ユーザー関数呼び出し
+			const fnName = block.type.split(':')[1];
+			const fn = scope.getState(fnName);
+			const args = {} as Record<string, any>;
+			for (let i = 0; i < fn.slots.length; i++) {
+				const name = fn.slots[i];
+				args[name] = this.evaluate(block.args[i], scope);
+			}
+			return fn.exec(args);
+		}
+
+		if (block.args === undefined) return null;
+
+		const date = new Date();
+		const day = `${this.opts.visitor ? this.opts.visitor.id : ''} ${date.getFullYear()}/${date.getMonth() + 1}/${date.getDate()}`;
+
+		const funcs: { [p in keyof typeof funcDefs]: Function } = {
+			not: (a: boolean) => !a,
+			or: (a: boolean, b: boolean) => a || b,
+			and: (a: boolean, b: boolean) => a && b,
+			eq: (a: any, b: any) => a === b,
+			notEq: (a: any, b: any) => a !== b,
+			gt: (a: number, b: number) => a > b,
+			lt: (a: number, b: number) => a < b,
+			gtEq: (a: number, b: number) => a >= b,
+			ltEq: (a: number, b: number) => a <= b,
+			if: (bool: boolean, a: any, b: any) => bool ? a : b,
+			for: (times: number, fn: Fn) => {
+				const result = [];
+				for (let i = 0; i < times; i++) {
+					result.push(fn.exec({
+						[fn.slots[0]]: i + 1
+					}));
+				}
+				return result;
+			},
+			add: (a: number, b: number) => a + b,
+			subtract: (a: number, b: number) => a - b,
+			multiply: (a: number, b: number) => a * b,
+			divide: (a: number, b: number) => a / b,
+			mod: (a: number, b: number) => a % b,
+			round: (a: number) => Math.round(a),
+			strLen: (a: string) => a.length,
+			strPick: (a: string, b: number) => a[b - 1],
+			strReplace: (a: string, b: string, c: string) => a.split(b).join(c),
+			strReverse: (a: string) => a.split('').reverse().join(''),
+			join: (texts: string[], separator: string) => texts.join(separator || ''),
+			stringToNumber: (a: string) => parseInt(a),
+			numberToString: (a: number) => a.toString(),
+			splitStrByLine: (a: string) => a.split('\n'),
+			pick: (list: any[], i: number) => list[i - 1],
+			listLen: (list: any[]) => list.length,
+			random: (probability: number) => Math.floor(seedrandom(`${this.opts.randomSeed}:${block.id}`)() * 100) < probability,
+			rannum: (min: number, max: number) => min + Math.floor(seedrandom(`${this.opts.randomSeed}:${block.id}`)() * (max - min + 1)),
+			randomPick: (list: any[]) => list[Math.floor(seedrandom(`${this.opts.randomSeed}:${block.id}`)() * list.length)],
+			dailyRandom: (probability: number) => Math.floor(seedrandom(`${day}:${block.id}`)() * 100) < probability,
+			dailyRannum: (min: number, max: number) => min + Math.floor(seedrandom(`${day}:${block.id}`)() * (max - min + 1)),
+			dailyRandomPick: (list: any[]) => list[Math.floor(seedrandom(`${day}:${block.id}`)() * list.length)],
+			seedRandom: (seed: any, probability: number) => Math.floor(seedrandom(seed)() * 100) < probability,
+			seedRannum: (seed: any, min: number, max: number) => min + Math.floor(seedrandom(seed)() * (max - min + 1)),
+			seedRandomPick: (seed: any, list: any[]) => list[Math.floor(seedrandom(seed)() * list.length)],
+			DRPWPM: (list: string[]) => {
+				const xs = [];
+				let totalFactor = 0;
+				for (const x of list) {
+					const parts = x.split(' ');
+					const factor = parseInt(parts.pop()!, 10);
+					const text = parts.join(' ');
+					totalFactor += factor;
+					xs.push({ factor, text });
+				}
+				const r = seedrandom(`${day}:${block.id}`)() * totalFactor;
+				let stackedFactor = 0;
+				for (const x of xs) {
+					if (r >= stackedFactor && r <= stackedFactor + x.factor) {
+						return x.text;
+					} else {
+						stackedFactor += x.factor;
+					}
+				}
+				return xs[0].text;
+			},
+		};
+
+		const fnName = block.type;
+		const fn = (funcs as any)[fnName];
+		if (fn == null) {
+			throw new AiScriptError(`No such function '${fnName}'`);
+		} else {
+			return fn(...block.args.map(x => this.evaluate(x, scope)));
+		}
+	}
+}
+
+class AiScriptError extends Error {
+	public info?: any;
+
+	constructor(message: string, info?: any) {
+		super(message);
+
+		this.info = info;
+
+		// Maintains proper stack trace for where our error was thrown (only available on V8)
+		if (Error.captureStackTrace) {
+			Error.captureStackTrace(this, AiScriptError);
+		}
+	}
+}
+
+class Scope {
+	private layerdStates: Record<string, any>[];
+	public name: string;
+
+	constructor(layerdStates: Scope['layerdStates'], name?: Scope['name']) {
+		this.layerdStates = layerdStates;
+		this.name = name || 'anonymous';
+	}
+
+	@autobind
+	public createChildScope(states: Record<string, any>, name?: Scope['name']): Scope {
+		const layer = [states, ...this.layerdStates];
+		return new Scope(layer, name);
+	}
+
+	/**
+	 * 指定した名前の変数の値を取得します
+	 * @param name 変数名
+	 */
+	@autobind
+	public getState(name: string): any {
+		for (const later of this.layerdStates) {
+			const state = later[name];
+			if (state !== undefined) {
+				return state;
+			}
+		}
+
+		throw new AiScriptError(
+			`No such variable '${name}' in scope '${this.name}'`, {
+				scope: this.layerdStates
+			});
+	}
+}