ARK-OS/arkos/arkrt/ArkGraphics/ArkWrite.swift

//
// 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.
//

import ark.sys.libc

public class ArkWrite {
    private let graphics: ArkGraphics

    public init(graphics: ArkGraphics) {
        self.graphics = graphics
    }

    public func drawText(_ text: String, x: Int, y: Int, size: Int, r: UInt8, g: UInt8, b: UInt8) {
        var cursorX = x
        
        var charW = ArkFontRobotoBold.charWidth
        var charH = ArkFontRobotoBold.charHeight
        var fontData = ArkFontRobotoBold.data
        var drawScale = size
        
        if size % 6 == 0 {
            charW = ArkFontRobotoBold.charWidth6x
            charH = ArkFontRobotoBold.charHeight6x
            fontData = ArkFontRobotoBold.data6x
            drawScale = size / 6
        } else if size % 4 == 0 {
            charW = ArkFontRobotoBold.charWidth4x
            charH = ArkFontRobotoBold.charHeight4x
            fontData = ArkFontRobotoBold.data4x
            drawScale = size / 4
        } else if size % 3 == 0 {
            charW = ArkFontRobotoBold.charWidth3x
            charH = ArkFontRobotoBold.charHeight3x
            fontData = ArkFontRobotoBold.data3x
            drawScale = size / 3
        } else if size % 2 == 0 {
            charW = ArkFontRobotoBold.charWidth2x
            charH = ArkFontRobotoBold.charHeight2x
            fontData = ArkFontRobotoBold.data2x
            drawScale = size / 2
        }
        
        for char in text {
            let ascii = char.asciiValue ?? 63 // '?' as fallback
            var max_col = -1
            var min_col = charW
            
            if ascii >= 32 && ascii <= 126 {
                let offset = Int(ascii - 32) * (charW * charH)
                
                // First pass: find bounding box
                for row in 0..<charH {
                    for col in 0..<charW {
                        let alpha = fontData[offset + row * charW + col]
                        if alpha > 0 {
                            if col < min_col { min_col = col }
                            if col > max_col { max_col = col }
                        }
                    }
                }
                
                // Second pass: draw
                if max_col != -1 {
                    for row in 0..<charH {
                        for col in min_col...max_col {
                            let alpha = fontData[offset + row * charW + col]
                            if alpha > 0 {
                                graphics.fillRectRGBA(
                                    x: cursorX + (col - min_col) * drawScale,
                                    y: y + (charH - 1 - row) * drawScale,
                                    w: drawScale,
                                    h: drawScale,
                                    r: r, g: g, b: b, a: alpha
                                )
                            }
                        }
                    }
                }
            }
            
            var charActualW = 0
            if max_col == -1 && ascii == 32 {
                charActualW = charW / 3
            } else if max_col != -1 {
                charActualW = (max_col - min_col + 1) + (charW / 16) // Padding between chars
            } else {
                charActualW = charW / 2
            }
            cursorX += charActualW * drawScale
        }
    }

    public static func measureText(_ text: String, size: Int) -> ArkSize {
        var cursorX = 0
        
        var charW = ArkFontRobotoBold.charWidth
        var charH = ArkFontRobotoBold.charHeight
        var fontData = ArkFontRobotoBold.data
        var drawScale = size
        
        if size % 6 == 0 {
            charW = ArkFontRobotoBold.charWidth6x
            charH = ArkFontRobotoBold.charHeight6x
            fontData = ArkFontRobotoBold.data6x
            drawScale = size / 6
        } else if size % 4 == 0 {
            charW = ArkFontRobotoBold.charWidth4x
            charH = ArkFontRobotoBold.charHeight4x
            fontData = ArkFontRobotoBold.data4x
            drawScale = size / 4
        } else if size % 3 == 0 {
            charW = ArkFontRobotoBold.charWidth3x
            charH = ArkFontRobotoBold.charHeight3x
            fontData = ArkFontRobotoBold.data3x
            drawScale = size / 3
        } else if size % 2 == 0 {
            charW = ArkFontRobotoBold.charWidth2x
            charH = ArkFontRobotoBold.charHeight2x
            fontData = ArkFontRobotoBold.data2x
            drawScale = size / 2
        }
        
        for char in text {
            let ascii = char.asciiValue ?? 63 // '?' as fallback
            var max_col = -1
            var min_col = charW
            
            if ascii >= 32 && ascii <= 126 {
                let offset = Int(ascii - 32) * (charW * charH)
                
                for row in 0..<charH {
                    for col in 0..<charW {
                        let alpha = fontData[offset + row * charW + col]
                        if alpha > 0 {
                            if col < min_col { min_col = col }
                            if col > max_col { max_col = col }
                        }
                    }
                }
            }
            
            var charActualW = 0
            if max_col == -1 && ascii == 32 {
                charActualW = charW / 3
            } else if max_col != -1 {
                charActualW = (max_col - min_col + 1) + (charW / 16)
            } else {
                charActualW = charW / 2
            }
            cursorX += charActualW * drawScale
        }
        
        return ArkSize(w: cursorX, h: charH * drawScale)
    }
}