from pulse.js import Array, Set, Map, Date, Promise, Error, Number, Object, RegExp, String, WeakMap, WeakSet

from pulse.js import Array

@ps.javascript
def example():
    arr = Array(10)              # -> new Array(10)
    arr = Array(1, 2, 3)         # -> new Array(1, 2, 3)

from pulse.js import Array

@ps.javascript
def process_items(items):
    # Filter and map
    result = Array.from_(items).filter(
        lambda x, i, arr: x > 0
    ).map(
        lambda x, i, arr: x * 2
    )

    # Reduce
    total = result.reduce(lambda acc, x, i, arr: acc + x, 0)

    return total

from pulse.js import Date

@ps.javascript
def example():
    now = Date()                      # -> new Date()
    specific = Date("2024-01-15")     # -> new Date("2024-01-15")
    timestamp = Date.now()            # -> Date.now()

from pulse.js import Error, throw
from pulse.js.error import TypeError, RangeError, ReferenceError

@ps.javascript
def example():
    throw(Error("Something went wrong"))
    throw(TypeError("Expected a string"))

from pulse.js import Error, throw

@ps.javascript
def validate(value):
    if value < 0:
        throw(RangeError("Value must be non-negative"))
    return value

from pulse.js import Map

@ps.javascript
def example():
    m = Map()                         # -> new Map()
    m = Map([["a", 1], ["b", 2]])     # -> new Map([["a", 1], ["b", 2]])

from pulse.js import Map

@ps.javascript
def build_lookup(items):
    lookup = Map()
    for item in items:
        lookup.set(item.id, item)

    if lookup.has("abc"):
        return lookup.get("abc")
    return None

from pulse.js import Number

@ps.javascript
def example():
    Number.isFinite(42)           # -> Number.isFinite(42)
    Number.MAX_SAFE_INTEGER       # -> Number.MAX_SAFE_INTEGER

from pulse.js import Object

@ps.javascript
def example():
    keys = Object.keys(data)          # -> Object.keys(data)
    merged = Object.assign({}, a, b)  # -> Object.assign({}, a, b)

from pulse.js import Promise

@ps.javascript
async def example():
    result = await Promise.resolve(42)
    data = await fetch("/api/data")

Promise(lambda resolve, reject: ...)

@ps.javascript
async def fetch_data():
    response = await fetch("/api/data")
    data = await response.json()
    return data

from pulse.js import RegExp

@ps.javascript
def example():
    pattern = RegExp(r"\d+", "g")     # -> new RegExp("\\d+", "g")
    if pattern.test("abc123"):
        matches = pattern.exec("abc123")

from pulse.js import Set

@ps.javascript
def example():
    s = Set()                         # -> new Set()
    s = Set([1, 2, 3])                # -> new Set([1, 2, 3])

from pulse.js import String

@ps.javascript
def example():
    String.fromCharCode(65)           # -> String.fromCharCode(65) -> "A"
    String.fromCodePoint(0x1F600)     # -> String.fromCodePoint(0x1F600) -> emoji

from pulse.js import WeakMap

@ps.javascript
def example():
    cache = WeakMap()
    cache.set(obj, "value")

from pulse.js import WeakSet

@ps.javascript
def example():
    seen = WeakSet()
    seen.add(obj)

from pulse.js import obj

@ps.javascript
def example():
    style = obj(color="red", fontSize="14px")  # -> { color: "red", fontSize: "14px" }

    # With spread
    merged = obj(**base, newKey="value")       # -> { ...base, newKey: "value" }

from pulse.js import undefined

@ps.javascript
def example():
    if value is undefined:
        return "missing"

from pulse.js import throw, Error

@ps.javascript
def validate(x):
    if x < 0:
        throw(Error("Must be positive"))