import PureYAML
@testable import PureYAMLJSON
import Testing

@Suite("JSON Writer")
struct JSONWriterTests {
    @Test("Emits a compact object on one line")
    func test_emitsCompactObject() throws {
        let value = try PureYAML.parse("a: 1\nb:\n  - true\n  - null")
        let json = try PureYAML.JSON.Writer.string(from: value, options: .compact)
        #expect(json == "{\"a\":1,\"b\":[true,null]}")
    }

    @Test("Pretty output indents and survives a round-trip")
    func test_emitsPrettyObject() throws {
        let value = try PureYAML.parse("a: 1\nb:\n  - x")
        let json = try PureYAML.JSON.Writer.string(from: value, options: .pretty)
        #expect(json.contains("\n"))
        #expect(try PureYAML.parse(json) == value)
    }

    @Test("Empty containers emit as [] and {}")
    func test_emitsEmptyContainers() throws {
        let object = try PureYAML.JSON.Writer.string(from: .mapping(.init([])), options: .compact)
        let array = try PureYAML.JSON.Writer.string(from: .sequence([]), options: .compact)
        #expect(object == "{}")
        #expect(array == "[]")
    }

    @Test("A non-string mapping key is rejected")
    func test_rejectsNonStringKey() {
        let value = PureYAML.Model.Value.mapping(.init([.init(keyNode: .sequence([.int(1)]), value: .int(2))]))
        #expect(throws: PureYAML.JSON.Writer.Failure.self) {
            _ = try PureYAML.JSON.Writer.string(from: value)
        }
    }

    @Test("A non-finite number is rejected")
    func test_rejectsNonFiniteNumber() {
        #expect(throws: PureYAML.JSON.Writer.Failure.nonFiniteNumber(.infinity)) {
            _ = try PureYAML.JSON.Writer.string(from: .double(.infinity))
        }
    }

    @Test("Control characters and quotes are escaped per RFC 8259")
    func test_escapesControlCharacters() throws {
        let json = try PureYAML.JSON.Writer.string(from: .string("a\"b\\c\n\u{01}"), options: .compact)
        #expect(json == "\"a\\\"b\\\\c\\n\\u0001\"")
    }
}