//! Functions related to line segments.

use anyhow::Result;
use derive_docs::stdlib;
use schemars::JsonSchema;

use crate::{
    errors::{KclError, KclErrorDetails},
    executor::{KclValue, SketchGroup, TagIdentifier},
    std::{utils::between, Args},
};

/// Returns the segment end of x.
pub async fn segment_end_x(args: Args) -> Result<KclValue, KclError> {
    let tag: TagIdentifier = args.get_data()?;
    let result = inner_segment_end_x(&tag, args.clone())?;

    args.make_user_val_from_f64(result)
}

/// Compute the ending point of the provided line segment along the 'x' axis.
///
/// ```no_run
/// const exampleSketch = startSketchOn('XZ')
///   |> startProfileAt([0, 0], %)
///   |> line([20, 0], %, $thing)
///   |> line([0, 5], %)
///   |> line([segEndX(thing), 0], %)
///   |> line([-20, 10], %)
///   |> close(%)
///  
/// const example = extrude(5, exampleSketch)
/// ```
#[stdlib {
    name = "segEndX",
}]
fn inner_segment_end_x(tag: &TagIdentifier, args: Args) -> Result<f64, KclError> {
    let line = args.get_tag_engine_info(tag)?;
    let path = line.path.clone().ok_or_else(|| {
        KclError::Type(KclErrorDetails {
            message: format!("Expected a line segment with a path, found `{:?}`", line),
            source_ranges: vec![args.source_range],
        })
    })?;

    Ok(path.to[0])
}

/// Returns the segment end of y.
pub async fn segment_end_y(args: Args) -> Result<KclValue, KclError> {
    let tag: TagIdentifier = args.get_data()?;
    let result = inner_segment_end_y(&tag, args.clone())?;

    args.make_user_val_from_f64(result)
}

/// Compute the ending point of the provided line segment along the 'y' axis.
///
/// ```no_run
/// const exampleSketch = startSketchOn('XZ')
///   |> startProfileAt([0, 0], %)
///   |> line([20, 0], %)
///   |> line([0, 3], %, $thing)
///   |> line([-10, 0], %)
///   |> line([0, segEndY(thing)], %)
///   |> line([-10, 0], %)
///   |> close(%)
///  
/// const example = extrude(5, exampleSketch)
/// ```
#[stdlib {
    name = "segEndY",
}]
fn inner_segment_end_y(tag: &TagIdentifier, args: Args) -> Result<f64, KclError> {
    let line = args.get_tag_engine_info(tag)?;
    let path = line.path.clone().ok_or_else(|| {
        KclError::Type(KclErrorDetails {
            message: format!("Expected a line segment with a path, found `{:?}`", line),
            source_ranges: vec![args.source_range],
        })
    })?;

    Ok(path.to[1])
}

/// Returns the last segment of x.
pub async fn last_segment_x(args: Args) -> Result<KclValue, KclError> {
    let sketch_group = args.get_sketch_group()?;
    let result = inner_last_segment_x(sketch_group, args.clone())?;

    args.make_user_val_from_f64(result)
}

/// Extract the 'x' axis value of the last line segment in the provided 2-d
/// sketch.
///
/// ```no_run
/// const exampleSketch = startSketchOn("XZ")
///   |> startProfileAt([0, 0], %)
///   |> line([5, 0], %)
///   |> line([20, 5], %)
///   |> line([lastSegX(%), 0], %)
///   |> line([-15, 0], %)
///   |> close(%)
///
/// const example = extrude(5, exampleSketch)
/// ```
#[stdlib {
    name = "lastSegX",
}]
fn inner_last_segment_x(sketch_group: Box<SketchGroup>, args: Args) -> Result<f64, KclError> {
    let last_line = sketch_group
        .value
        .last()
        .ok_or_else(|| {
            KclError::Type(KclErrorDetails {
                message: format!(
                    "Expected a SketchGroup with at least one segment, found `{:?}`",
                    sketch_group
                ),
                source_ranges: vec![args.source_range],
            })
        })?
        .get_base();

    Ok(last_line.to[0])
}

/// Returns the last segment of y.
pub async fn last_segment_y(args: Args) -> Result<KclValue, KclError> {
    let sketch_group = args.get_sketch_group()?;
    let result = inner_last_segment_y(sketch_group, args.clone())?;

    args.make_user_val_from_f64(result)
}

/// Extract the 'y' axis value of the last line segment in the provided 2-d
/// sketch.
///
/// ```no_run
/// const exampleSketch = startSketchOn("XZ")
///   |> startProfileAt([0, 0], %)
///   |> line([5, 0], %)
///   |> line([20, 5], %)
///   |> line([0, lastSegY(%)], %)
///   |> line([-15, 0], %)
///   |> close(%)
///
/// const example = extrude(5, exampleSketch)
/// ```
#[stdlib {
    name = "lastSegY",
}]
fn inner_last_segment_y(sketch_group: Box<SketchGroup>, args: Args) -> Result<f64, KclError> {
    let last_line = sketch_group
        .value
        .last()
        .ok_or_else(|| {
            KclError::Type(KclErrorDetails {
                message: format!(
                    "Expected a SketchGroup with at least one segment, found `{:?}`",
                    sketch_group
                ),
                source_ranges: vec![args.source_range],
            })
        })?
        .get_base();

    Ok(last_line.to[1])
}

/// Returns the length of the segment.
pub async fn segment_length(args: Args) -> Result<KclValue, KclError> {
    let tag: TagIdentifier = args.get_data()?;
    let result = inner_segment_length(&tag, args.clone())?;
    args.make_user_val_from_f64(result)
}

/// Compute the length of the provided line segment.
///
/// ```no_run
/// const exampleSketch = startSketchOn("XZ")
///   |> startProfileAt([0, 0], %)
///   |> angledLine({
///     angle: 60,
///     length: 10,
///   }, %, $thing)
///   |> tangentialArc({
///     offset: -120,
///     radius: 5,
///   }, %)
///   |> angledLine({
///     angle: -60,
///     length: segLen(thing),
///   }, %)
///   |> close(%)
///
/// const example = extrude(5, exampleSketch)
/// ```
#[stdlib {
    name = "segLen",
}]
fn inner_segment_length(tag: &TagIdentifier, args: Args) -> Result<f64, KclError> {
    let line = args.get_tag_engine_info(tag)?;
    let path = line.path.clone().ok_or_else(|| {
        KclError::Type(KclErrorDetails {
            message: format!("Expected a line segment with a path, found `{:?}`", line),
            source_ranges: vec![args.source_range],
        })
    })?;

    let result = ((path.from[1] - path.to[1]).powi(2) + (path.from[0] - path.to[0]).powi(2)).sqrt();

    Ok(result)
}

/// Returns the angle of the segment.
pub async fn segment_angle(args: Args) -> Result<KclValue, KclError> {
    let tag: TagIdentifier = args.get_data()?;

    let result = inner_segment_angle(&tag, args.clone())?;
    args.make_user_val_from_f64(result)
}

/// Compute the angle (in degrees) of the provided line segment.
///
/// ```no_run
/// const exampleSketch = startSketchOn('XZ')
///   |> startProfileAt([0, 0], %)
///   |> line([10, 0], %)
///   |> line([5, 10], %, $seg01)
///   |> line([-10, 0], %)
///   |> angledLine([segAng(seg01), 10], %)
///   |> line([-10, 0], %)
///   |> angledLine([segAng(seg01), -15], %)
///   |> close(%)
///
/// const example = extrude(4, exampleSketch)
/// ```
#[stdlib {
    name = "segAng",
}]
fn inner_segment_angle(tag: &TagIdentifier, args: Args) -> Result<f64, KclError> {
    let line = args.get_tag_engine_info(tag)?;
    let path = line.path.clone().ok_or_else(|| {
        KclError::Type(KclErrorDetails {
            message: format!("Expected a line segment with a path, found `{:?}`", line),
            source_ranges: vec![args.source_range],
        })
    })?;

    let result = between(path.from.into(), path.to.into());

    Ok(result.degrees())
}

/// Returns the angle to match the given length for x.
pub async fn angle_to_match_length_x(args: Args) -> Result<KclValue, KclError> {
    let (tag, to, sketch_group) = args.get_tag_to_number_sketch_group()?;
    let result = inner_angle_to_match_length_x(&tag, to, sketch_group, args.clone())?;
    args.make_user_val_from_f64(result)
}

/// Compute the angle (in degrees) in o
///
/// ```no_run
/// const sketch001 = startSketchOn('XZ')
///   |> startProfileAt([0, 0], %)
///   |> line([2, 5], %, $seg01)
///   |> angledLineToX([
///        -angleToMatchLengthX(seg01, 7, %),
///        10
///      ], %)
///   |> close(%)
///
/// const extrusion = extrude(5, sketch001)
/// ```
#[stdlib {
    name = "angleToMatchLengthX",
}]
fn inner_angle_to_match_length_x(
    tag: &TagIdentifier,
    to: f64,
    sketch_group: Box<SketchGroup>,
    args: Args,
) -> Result<f64, KclError> {
    let line = args.get_tag_engine_info(tag)?;
    let path = line.path.clone().ok_or_else(|| {
        KclError::Type(KclErrorDetails {
            message: format!("Expected a line segment with a path, found `{:?}`", line),
            source_ranges: vec![args.source_range],
        })
    })?;

    let length = ((path.from[1] - path.to[1]).powi(2) + (path.from[0] - path.to[0]).powi(2)).sqrt();

    let last_line = sketch_group
        .value
        .last()
        .ok_or_else(|| {
            KclError::Type(KclErrorDetails {
                message: format!(
                    "Expected a SketchGroup with at least one segment, found `{:?}`",
                    sketch_group
                ),
                source_ranges: vec![args.source_range],
            })
        })?
        .get_base();

    let diff = (to - last_line.to[0]).abs();

    let angle_r = (diff / length).acos();

    if diff > length {
        Ok(0.0)
    } else {
        Ok(angle_r.to_degrees())
    }
}

/// Returns the angle to match the given length for y.
pub async fn angle_to_match_length_y(args: Args) -> Result<KclValue, KclError> {
    let (tag, to, sketch_group) = args.get_tag_to_number_sketch_group()?;
    let result = inner_angle_to_match_length_y(&tag, to, sketch_group, args.clone())?;
    args.make_user_val_from_f64(result)
}

/// Returns the angle to match the given length for y.
///
/// ```no_run
/// const sketch001 = startSketchOn('XZ')
///   |> startProfileAt([0, 0], %)
///   |> line([1, 2], %, $seg01)
///   |> angledLine({
///     angle: angleToMatchLengthY(seg01, 15, %),
///     length: 5,
///     }, %)
///   |> yLineTo(0, %)
///   |> close(%)
///  
/// const extrusion = extrude(5, sketch001)
/// ```
#[stdlib {
    name = "angleToMatchLengthY",
}]
fn inner_angle_to_match_length_y(
    tag: &TagIdentifier,
    to: f64,
    sketch_group: Box<SketchGroup>,
    args: Args,
) -> Result<f64, KclError> {
    let line = args.get_tag_engine_info(tag)?;
    let path = line.path.clone().ok_or_else(|| {
        KclError::Type(KclErrorDetails {
            message: format!("Expected a line segment with a path, found `{:?}`", line),
            source_ranges: vec![args.source_range],
        })
    })?;

    let length = ((path.from[1] - path.to[1]).powi(2) + (path.from[0] - path.to[0]).powi(2)).sqrt();

    let last_line = sketch_group
        .value
        .last()
        .ok_or_else(|| {
            KclError::Type(KclErrorDetails {
                message: format!(
                    "Expected a SketchGroup with at least one segment, found `{:?}`",
                    sketch_group
                ),
                source_ranges: vec![args.source_range],
            })
        })?
        .get_base();

    let diff = (to - last_line.to[1]).abs();

    let angle_r = (diff / length).asin();

    if diff > length {
        Ok(0.0)
    } else {
        Ok(angle_r.to_degrees())
    }
}