import type { VmValue } from '@mirascript/mirascript';
import type { Scope } from './scope.js';
import type { ExpressionSource } from './expression.js';
import { BaseState } from './migrator/state.js';
import { Evaluator } from './main.js';
import { DefaultVmContext } from '@mirascript/mirascript/subtle';

const evaluator = new Evaluator();
/** MathJs 表达式转为 MiraScript 表达式 */
function migrate<const T extends VmValue>(
    expr: ExpressionSource<T>,
    condition: boolean,
    context: Scope | undefined,
): ExpressionSource<T> {
    const dispose = context?.reset(evaluator);
    try {
        const state = new BaseState(expr, condition, context ? context.proxy : DefaultVmContext);
        state.migrate();
        return state.result() as ExpressionSource<T>;
    } finally {
        dispose?.();
    }
}

/** MathJs 表达式转为 MiraScript 表达式 */
export function migrateMathJs<const T extends VmValue>(
    expr: ExpressionSource<T>,
    condition: boolean,
    context: Scope | undefined,
): ExpressionSource<T> {
    // 检查输入
    if (!expr) return '' as ExpressionSource<T>;
    expr = expr.trim() as ExpressionSource<T>;
    if (!expr || expr === 'undefined') return '' as ExpressionSource<T>;
    if (expr === 'null' || expr === 'nil') return 'nil' as ExpressionSource<T>;
    if (expr === 'true') return 'true' as ExpressionSource<T>;
    if (expr === 'false') return 'false' as ExpressionSource<T>;
    if (condition) {
        // 兼容旧的 evaluateCondition 的宽容处理
        if (expr === 'True' || expr === 'TRUE' || expr === '1' || expr === '"1"' || expr === "'1'")
            return 'true' as ExpressionSource<T>;
        if (
            expr === 'False' ||
            expr === 'FALSE' ||
            expr === '0' ||
            expr === '"0"' ||
            expr === "'0'" ||
            expr === '""' ||
            expr === "''"
        )
            return 'false' as ExpressionSource<T>;
    }
    if (/^[-+]?(\d+(?:\.\d+)?(?:[eE][+-]?\d+)?)$/.test(expr)) {
        return expr;
    }

    return migrate(expr, condition, context);
}