//
// Copyright 2026 Aarav Ravindra Kharade
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//


// ── Pure-libc utilities replacing Foundation APIs ─────────────────

/// Read an entire file into a String via fopen/fread (replaces String(contentsOfFile:)).
public func readFileContents(_ path: String) -> String? {
    guard let fp = fopen(path, "r") else { return nil }
    defer { fclose(fp) }

    var buffer = [UInt8](repeating: 0, count: 8192)
    var result = ""
    while true {
        let n = fread(&buffer, 1, buffer.count, fp)
        if n == 0 { break }
        buffer.withUnsafeBufferPointer { ptr in
            let slice = UnsafeBufferPointer(start: ptr.baseAddress, count: n)
            for byte in slice {
                result.append(Character(UnicodeScalar(byte)))
            }
        }
    }
    return result.isEmpty ? nil : result
}

/// Trim whitespace and newlines from both ends of a string (replaces .trimmingCharacters(in:)).
public func trimWhitespace(_ s: String) -> String {
    var chars = Array(s)
    while let first = chars.first, first == " " || first == "\n" || first == "\r" || first == "\t" {
        chars.removeFirst()
    }
    while let last = chars.last, last == " " || last == "\n" || last == "\r" || last == "\t" {
        chars.removeLast()
    }
    return String(chars)
}

/// Simple snprintf-style format for a single Double with one decimal place.
public func formatDouble(_ value: Double, decimals: Int = 1) -> String {
    let intPart = Int(value)
    var factor = 1
    for _ in 0..<decimals { factor *= 10 }
    let fracPart = abs(Int((value - Double(intPart)) * Double(factor)))
    return "\(intPart).\(fracPart)"
}