printwell-pdf 0.1.6

//! PDF annotation support.
//!
//! This module provides functionality for adding annotations
//! to PDF documents using `PDFium` via FFI.
//!
//! # Example
//!
//! ```ignore
//! use printwell_pdf::annotations::{add_annotations, Annotation, AnnotationType, Rect, Color};
//!
//! let annotations = vec![
//!     Annotation::builder()
//!         .annotation_type(AnnotationType::Highlight)
//!         .page(1)
//!         .rect(Rect::new(100.0, 700.0, 200.0, 20.0))
//!         .color(Color::yellow())
//!         .build(),
//! ];
//!
//! let result = add_annotations(&pdf_data, &annotations)?;
//! ```

use crate::Result;
use typed_builder::TypedBuilder;

/// Annotation types supported by `PDFium`
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum AnnotationType {
    /// Highlight text markup
    Highlight,
    /// Underline text markup
    Underline,
    /// Strikeout text markup
    Strikeout,
    /// Squiggly underline text markup
    Squiggly,
    /// Sticky note annotation
    Text,
    /// Free text annotation (text box)
    FreeText,
    /// Line annotation
    Line,
    /// Square/rectangle annotation
    Square,
    /// Circle/ellipse annotation
    Circle,
    /// Ink/freehand annotation
    Ink,
    /// Stamp annotation
    Stamp,
    /// Link annotation
    Link,
}

impl AnnotationType {
    /// Convert to `PDFium` annotation type constant
    #[must_use]
    pub const fn to_pdfium_type(&self) -> i32 {
        match self {
            Self::Highlight => 9,  // FPDF_ANNOT_HIGHLIGHT
            Self::Underline => 10, // FPDF_ANNOT_UNDERLINE
            Self::Strikeout => 11, // FPDF_ANNOT_STRIKEOUT
            Self::Squiggly => 12,  // FPDF_ANNOT_SQUIGGLY
            Self::Text => 1,       // FPDF_ANNOT_TEXT
            Self::FreeText => 3,   // FPDF_ANNOT_FREETEXT
            Self::Line => 4,       // FPDF_ANNOT_LINE
            Self::Square => 5,     // FPDF_ANNOT_SQUARE
            Self::Circle => 6,     // FPDF_ANNOT_CIRCLE
            Self::Ink => 15,       // FPDF_ANNOT_INK
            Self::Stamp => 13,     // FPDF_ANNOT_STAMP
            Self::Link => 2,       // FPDF_ANNOT_LINK
        }
    }

    /// Create from `PDFium` annotation type constant
    #[must_use]
    pub const fn from_pdfium_type(t: i32) -> Option<Self> {
        match t {
            9 => Some(Self::Highlight),
            10 => Some(Self::Underline),
            11 => Some(Self::Strikeout),
            12 => Some(Self::Squiggly),
            1 => Some(Self::Text),
            3 => Some(Self::FreeText),
            4 => Some(Self::Line),
            5 => Some(Self::Square),
            6 => Some(Self::Circle),
            15 => Some(Self::Ink),
            13 => Some(Self::Stamp),
            2 => Some(Self::Link),
            _ => None,
        }
    }
}

/// Rectangle for annotation bounds
#[derive(Debug, Clone, Copy, TypedBuilder)]
pub struct Rect {
    /// X coordinate (from left)
    pub x: f32,
    /// Y coordinate (from bottom)
    pub y: f32,
    /// Width
    pub width: f32,
    /// Height
    pub height: f32,
}

impl Rect {
    /// Create a new rectangle
    #[must_use]
    pub const fn new(x: f32, y: f32, width: f32, height: f32) -> Self {
        Self {
            x,
            y,
            width,
            height,
        }
    }
}

/// Color for annotations
#[derive(Debug, Clone, Copy)]
pub struct Color {
    /// Red component (0-255)
    pub r: u8,
    /// Green component (0-255)
    pub g: u8,
    /// Blue component (0-255)
    pub b: u8,
    /// Alpha component (0-255)
    pub a: u8,
}

impl Color {
    /// Create a new color
    #[must_use]
    pub const fn new(r: u8, g: u8, b: u8, a: u8) -> Self {
        Self { r, g, b, a }
    }

    /// Create a color from RGB values (fully opaque)
    #[must_use]
    pub const fn rgb(r: u8, g: u8, b: u8) -> Self {
        Self::new(r, g, b, 255)
    }

    /// Yellow color (for highlighting)
    #[must_use]
    pub const fn yellow() -> Self {
        Self::rgb(255, 255, 0)
    }

    /// Red color
    #[must_use]
    pub const fn red() -> Self {
        Self::rgb(255, 0, 0)
    }

    /// Green color
    #[must_use]
    pub const fn green() -> Self {
        Self::rgb(0, 255, 0)
    }

    /// Blue color
    #[must_use]
    pub const fn blue() -> Self {
        Self::rgb(0, 0, 255)
    }

    /// Black color
    #[must_use]
    pub const fn black() -> Self {
        Self::rgb(0, 0, 0)
    }

    /// White color
    #[must_use]
    pub const fn white() -> Self {
        Self::rgb(255, 255, 255)
    }

    /// Convert to RGBA u32 for FFI
    #[must_use]
    pub const fn to_rgba(&self) -> u32 {
        ((self.r as u32) << 24) | ((self.g as u32) << 16) | ((self.b as u32) << 8) | (self.a as u32)
    }

    /// Create from hex string (e.g., "#FF0000" or "FF0000")
    #[must_use]
    pub fn from_hex(hex: &str) -> Option<Self> {
        let hex = hex.trim_start_matches('#');
        if hex.len() == 6 {
            let r = u8::from_str_radix(&hex[0..2], 16).ok()?;
            let g = u8::from_str_radix(&hex[2..4], 16).ok()?;
            let b = u8::from_str_radix(&hex[4..6], 16).ok()?;
            Some(Self::rgb(r, g, b))
        } else if hex.len() == 8 {
            let r = u8::from_str_radix(&hex[0..2], 16).ok()?;
            let g = u8::from_str_radix(&hex[2..4], 16).ok()?;
            let b = u8::from_str_radix(&hex[4..6], 16).ok()?;
            let a = u8::from_str_radix(&hex[6..8], 16).ok()?;
            Some(Self::new(r, g, b, a))
        } else {
            None
        }
    }
}

impl Default for Color {
    fn default() -> Self {
        Self::yellow()
    }
}

/// An annotation to add to a PDF
#[derive(Debug, Clone, TypedBuilder)]
pub struct Annotation {
    /// Type of annotation
    pub annotation_type: AnnotationType,

    /// Page number (1-indexed)
    pub page: u32,

    /// Bounding rectangle
    pub rect: Rect,

    /// Annotation color
    #[builder(default)]
    pub color: Color,

    /// Opacity (0.0 = transparent, 1.0 = opaque)
    #[builder(default = 1.0)]
    pub opacity: f32,

    /// Note contents (for sticky notes, comments)
    #[builder(default, setter(into, strip_option))]
    pub contents: Option<String>,

    /// Author name
    #[builder(default, setter(into, strip_option))]
    pub author: Option<String>,

    /// Subject/title
    #[builder(default, setter(into, strip_option))]
    pub subject: Option<String>,

    /// Text for `FreeText` annotations
    #[builder(default, setter(into, strip_option))]
    pub text: Option<String>,

    /// Font size for `FreeText` annotations
    #[builder(default = 12.0)]
    pub font_size: f32,

    /// Points for line/ink annotations (pairs of x,y coordinates)
    #[builder(default)]
    pub points: Vec<(f32, f32)>,
}

/// Information about an existing annotation
#[derive(Debug, Clone)]
pub struct AnnotationInfo {
    /// Type of annotation
    pub annotation_type: AnnotationType,
    /// Page number (1-indexed)
    pub page: u32,
    /// Bounding rectangle
    pub rect: Rect,
    /// Annotation color
    pub color: Color,
    /// Opacity
    pub opacity: f32,
    /// Note contents
    pub contents: Option<String>,
    /// Author
    pub author: Option<String>,
}

/// Add annotations to a PDF document.
///
/// # Arguments
/// * `pdf_data` - The input PDF data
/// * `annotations` - The annotations to add
///
/// # Returns
/// The modified PDF data with annotations.
///
/// # Errors
///
/// Returns an error if the annotations cannot be added to the PDF.
pub fn add_annotations(pdf_data: &[u8], annotations: &[Annotation]) -> Result<Vec<u8>> {
    if annotations.is_empty() {
        return Ok(pdf_data.to_vec());
    }

    // Convert to FFI format
    let annotation_defs: Vec<printwell_sys::AnnotationDef> = annotations
        .iter()
        .map(|a| printwell_sys::AnnotationDef {
            annotation_type: a.annotation_type.to_pdfium_type(),
            page: i32::try_from(a.page).unwrap_or(i32::MAX),
            x: a.rect.x,
            y: a.rect.y,
            width: a.rect.width,
            height: a.rect.height,
            color: a.color.to_rgba(),
            opacity: a.opacity,
            contents: a.contents.clone().unwrap_or_default(),
            author: a.author.clone().unwrap_or_default(),
            text: a.text.clone().unwrap_or_default(),
            font_size: a.font_size,
        })
        .collect();

    // Call FFI function
    let result =
        printwell_sys::ffi::pdf_add_annotations(pdf_data, &annotation_defs).map_err(|e| {
            crate::AnnotationError::Operation(format!("Failed to add annotations: {e}"))
        })?;

    Ok(result)
}

/// List annotations in a PDF document.
///
/// # Arguments
/// * `pdf_data` - The input PDF data
///
/// # Returns
/// A list of annotations found in the document.
///
/// # Errors
///
/// Returns an error if the annotations cannot be listed from the PDF.
pub fn list_annotations(pdf_data: &[u8]) -> Result<Vec<AnnotationInfo>> {
    let annotation_defs = printwell_sys::ffi::pdf_list_annotations(pdf_data).map_err(|e| {
        crate::AnnotationError::Operation(format!("Failed to list annotations: {e}"))
    })?;

    let annotations = annotation_defs
        .iter()
        .filter_map(|a| {
            let annotation_type = AnnotationType::from_pdfium_type(a.annotation_type)?;
            Some(AnnotationInfo {
                annotation_type,
                page: u32::try_from(a.page).unwrap_or(0),
                rect: Rect::new(a.x, a.y, a.width, a.height),
                color: Color::new(
                    ((a.color >> 24) & 0xFF) as u8,
                    ((a.color >> 16) & 0xFF) as u8,
                    ((a.color >> 8) & 0xFF) as u8,
                    (a.color & 0xFF) as u8,
                ),
                opacity: a.opacity,
                contents: if a.contents.is_empty() {
                    None
                } else {
                    Some(a.contents.clone())
                },
                author: if a.author.is_empty() {
                    None
                } else {
                    Some(a.author.clone())
                },
            })
        })
        .collect();

    Ok(annotations)
}

/// Remove annotations from a PDF document.
///
/// # Arguments
/// * `pdf_data` - The input PDF data
/// * `page` - Optional page number to filter (None = all pages)
/// * `annotation_types` - Optional types to remove (None = all types)
///
/// # Returns
/// The modified PDF data with annotations removed.
///
/// # Errors
///
/// Returns an error if the annotations cannot be removed from the PDF.
pub fn remove_annotations(
    pdf_data: &[u8],
    page: Option<u32>,
    annotation_types: Option<&[AnnotationType]>,
) -> Result<Vec<u8>> {
    let page_filter: i32 = page.map_or(-1, |p| i32::try_from(p).unwrap_or(i32::MAX));
    let type_filter: Vec<i32> = annotation_types
        .map(|types| types.iter().map(AnnotationType::to_pdfium_type).collect())
        .unwrap_or_default();

    let result = printwell_sys::ffi::pdf_remove_annotations(pdf_data, page_filter, &type_filter)
        .map_err(|e| {
            crate::AnnotationError::Operation(format!("Failed to remove annotations: {e}"))
        })?;

    Ok(result)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_color_from_hex() {
        let c = Color::from_hex("#FF0000").unwrap();
        assert_eq!(c.r, 255);
        assert_eq!(c.g, 0);
        assert_eq!(c.b, 0);
        assert_eq!(c.a, 255);

        let c = Color::from_hex("00FF00").unwrap();
        assert_eq!(c.r, 0);
        assert_eq!(c.g, 255);
        assert_eq!(c.b, 0);
    }

    #[test]
    fn test_annotation_type_conversion() {
        let types = [
            AnnotationType::Highlight,
            AnnotationType::Underline,
            AnnotationType::Text,
            AnnotationType::FreeText,
        ];

        for t in &types {
            let pdfium = t.to_pdfium_type();
            let back = AnnotationType::from_pdfium_type(pdfium);
            assert_eq!(back, Some(*t));
        }
    }
}