use std::collections::HashMap;

use crate::params::chat::{
    ChatCompletionParameters, ChatMessage, ChatMessageContent, ChatMessageContentPart,
};
use anyhow::{Result, anyhow};
use candle_core::{DType, Device, IndexOp, Shape, Tensor};
#[cfg(feature = "ffmpeg")]
use ffmpeg_next as ffmpeg;
use image::DynamicImage;
use num::integer::lcm;

use crate::{
    models::qwen2_5vl::config::VisionSetting,
    utils::{
        img_utils::get_image,
        {ceil_by_factor, floor_by_factor, round_by_factor},
    },
};

#[derive(Clone)]
pub struct VisionInput {
    pub data: Tensor,
    pub grid_thw: Tensor,
}

#[derive(Clone)]
pub struct GeneralInput {
    pub replace_text: String,
    pub pixel_values: Option<Tensor>,
    pub image_grid_thw: Option<Tensor>,
    pub pixel_values_video: Option<Tensor>,
    pub video_grid_thw: Option<Tensor>,
    pub second_per_grid_ts: Option<Vec<f32>>,
}

#[allow(unused)]
pub struct Qwen2_5VLProcessor {
    vision_setting: VisionSetting,
    device: Device,
    dtype: DType,
    image_token: String,
    video_token: String,
}

impl Qwen2_5VLProcessor {
    pub fn new(device: &Device, dtype: DType) -> Result<Self> {
        let vision_setting = VisionSetting::default();
        let image_token = "<|image_pad|>".to_string();
        let video_token = "<|video_pad|>".to_string();
        Ok(Self {
            vision_setting,
            device: device.clone(),
            dtype,
            image_token,
            video_token,
        })
    }

    pub fn extract_vision_info(
        &self,
        mes: &ChatCompletionParameters,
    ) -> Result<HashMap<String, Vec<String>>> {
        let mut vision_map = HashMap::new();
        vision_map.insert("image".to_string(), Vec::new());
        vision_map.insert("video".to_string(), Vec::new());
        for chat_mes in mes.messages.clone() {
            if let ChatMessage::User { content, .. } = chat_mes
                && let ChatMessageContent::ContentPart(part_vec) = content
            {
                for part in part_vec {
                    if let ChatMessageContentPart::Image(img_part) = part {
                        let img_url = img_part.image_url;
                        vision_map.get_mut("image").unwrap().push(img_url.url);
                        // } else if let ChatMessageContentPart::Video(video_part) = part {
                        //     let video_url = video_part.video_url;
                        //     vision_map.get_mut("video").unwrap().push(video_url.url);
                    }
                }
            }
        }
        Ok(vision_map)
    }

    pub fn process_img(
        &self,
        img: &DynamicImage,
        img_mean: &Tensor,
        img_std: &Tensor,
    ) -> Result<Tensor> {
        let img_h = img.height();
        let img_w = img.width();
        //  h,w resize成 28的倍数
        let (resize_h, resize_w) = smart_resize(img_h, img_w, &self.vision_setting, true, None)?;
        let img = img.resize_exact(resize_w, resize_h, image::imageops::FilterType::CatmullRom);
        let img_vec = img.to_rgb8().into_raw();
        // (h, w, c) => (c, h, w)
        let img_tensor = Tensor::from_slice(
            &img_vec,
            (resize_h as usize, resize_w as usize, 3),
            &self.device,
        )?
        .permute((2, 0, 1))?
        .to_dtype(self.dtype)?;
        // 0-255 rescale to 0-1
        let img_tensor = img_tensor.affine(1.0 / 255.0, 0.)?;
        // normalize
        let img_tensor = img_tensor.broadcast_sub(img_mean)?.broadcast_div(img_std)?;
        // (c, h, w) => (1, c, h, w)
        let img_tensor = img_tensor.unsqueeze(0)?;
        Ok(img_tensor)
    }

    pub fn process_vision_tensor(&self, img_tensor: &Tensor) -> Result<(Tensor, Tensor)> {
        // Check that data have `num_frames` divisible by `temporal_patch_size`
        // img_tensor: (t, c, h, w)
        let t = img_tensor.dim(0)?;
        let img_tensor = if t % self.vision_setting.temporal_patch_size != 0 {
            let repeat_num = self.vision_setting.temporal_patch_size
                - t % self.vision_setting.temporal_patch_size;
            let repeats = img_tensor.i(t - 1)?.repeat((repeat_num, 1, 1, 1))?;
            Tensor::cat(&[img_tensor, &repeats], 0)?
        } else {
            img_tensor.clone()
        };
        let channel = img_tensor.dim(1)?;
        let grid_t = img_tensor.dim(0)? / self.vision_setting.temporal_patch_size;
        let grid_h = img_tensor.dim(2)? / self.vision_setting.patch_size;
        let grid_w = img_tensor.dim(3)? / self.vision_setting.patch_size;
        let shape = Shape::from(vec![
            grid_t,
            self.vision_setting.temporal_patch_size,
            channel,
            grid_h / self.vision_setting.merge_size,
            self.vision_setting.merge_size,
            self.vision_setting.patch_size,
            grid_w / self.vision_setting.merge_size,
            self.vision_setting.merge_size,
            self.vision_setting.patch_size,
        ]);
        let img_tensor = img_tensor.reshape(shape)?;
        // shape to // grid_t,
        // grid_h / merge_size,
        // grid_w / merge_size,
        // merge_size,
        // merge_size,
        // channel,
        // temporal_patch_size,
        // patch_size,
        // patch_size,
        let img_tensor = img_tensor.permute(vec![0, 3, 6, 4, 7, 2, 1, 5, 8])?;
        let img_tensor = img_tensor
            .reshape((
                grid_t * grid_h * grid_w,
                channel
                    * self.vision_setting.temporal_patch_size
                    * self.vision_setting.patch_size
                    * self.vision_setting.patch_size,
            ))?
            .contiguous()?;
        let grid_thw = Tensor::from_vec(
            vec![grid_t as u32, grid_h as u32, grid_w as u32],
            (1, 3),
            &self.device,
        )?;
        Ok((img_tensor, grid_thw))
    }

    pub fn process_images(
        &self,
        imgs: Vec<DynamicImage>,
        img_mean: &Tensor,
        img_std: &Tensor,
    ) -> Result<VisionInput> {
        let mut pixel_values_vec = Vec::new();
        let mut vision_grid_thws_vec = Vec::new();

        for img in imgs {
            let img_tensor = self.process_img(&img, img_mean, img_std)?;
            let img_tensor = Tensor::cat(&[&img_tensor, &img_tensor], 0)?.contiguous()?;
            let (img_tensor, grid_thw) = self.process_vision_tensor(&img_tensor)?;
            pixel_values_vec.push(img_tensor);
            vision_grid_thws_vec.push(grid_thw);
        }
        let pixel_values = Tensor::cat(&pixel_values_vec, 0)?;
        let vision_grid_thws = Tensor::cat(&vision_grid_thws_vec, 0)?;
        Ok(VisionInput {
            data: pixel_values,
            grid_thw: vision_grid_thws,
        })
    }

    pub fn process_videos(
        &self,
        data: Vec<Tensor>,
        img_mean: &Tensor,
        img_std: &Tensor,
    ) -> Result<VisionInput> {
        let mut pixel_values_vec = Vec::new();
        let mut vision_grid_thws_vec = Vec::new();
        for single_video in data {
            // 0-255 rescale to 0-1
            let video_tensor = single_video.to_dtype(self.dtype)?.affine(1.0 / 255.0, 0.)?;
            // normalize
            let video_tensor = video_tensor
                .broadcast_sub(img_mean)?
                .broadcast_div(img_std)?
                .contiguous()?;
            let (video_tensor, video_grid_thw) = self.process_vision_tensor(&video_tensor)?;
            pixel_values_vec.push(video_tensor);
            vision_grid_thws_vec.push(video_grid_thw);
        }
        let pixel_values = Tensor::cat(&pixel_values_vec, 0)?.contiguous()?;
        let vision_grid_thws = Tensor::cat(&vision_grid_thws_vec, 0)?.contiguous()?;
        Ok(VisionInput {
            data: pixel_values,
            grid_thw: vision_grid_thws,
        })
    }

    #[allow(unused_mut)]
    pub fn process_info(
        &self,
        messages: &ChatCompletionParameters,
        text: &str,
    ) -> Result<GeneralInput> {
        let mut pixel_values = None;
        let mut image_grid_thw = None;
        let mut pixel_values_video = None;
        let mut video_grid_thw: Option<Tensor> = None;
        let mut second_per_grid_ts = None;
        let vision_map = self.extract_vision_info(messages)?;
        let img_mean =
            Tensor::from_slice(&self.vision_setting.image_mean, (3, 1, 1), &self.device)?
                .to_dtype(self.dtype)?;
        let img_std = Tensor::from_slice(&self.vision_setting.image_std, (3, 1, 1), &self.device)?
            .to_dtype(self.dtype)?;
        for (key, vec) in vision_map {
            // println!("key: {}, \nvalue: {:?}", key, vec);
            if key.eq("image") {
                let mut file_vec = Vec::new();
                for file in &vec {
                    let image = get_image(file);
                    match image {
                        Ok(img) => file_vec.push(img),
                        Err(e) => println!("get_image err: {e:?}"),
                    };
                }
                if !file_vec.is_empty() {
                    let vision_input = self.process_images(file_vec, &img_mean, &img_std);
                    match vision_input {
                        Ok(img_input) => {
                            pixel_values = Some(img_input.data);
                            image_grid_thw = Some(img_input.grid_thw);
                        }
                        Err(e) => println!("img process_images err: {e:?}"),
                    };
                }
            }
            #[cfg(feature = "ffmpeg")]
            if key.eq("video") {
                let mut file_vec = Vec::new();
                for file in &vec {
                    let video_data = get_video_data(file, &self.vision_setting, &self.device);
                    match video_data {
                        Ok(tensor) => file_vec.push(tensor),
                        Err(e) => println!("get_video_data err: {:?}", e),
                    };
                }
                if !file_vec.is_empty() {
                    let vision_input = self.process_videos(file_vec, &img_mean, &img_std);
                    match vision_input {
                        Ok(video_input) => {
                            let video_num = video_input.grid_thw.dim(0)?;
                            pixel_values_video = Some(video_input.data);
                            video_grid_thw = Some(video_input.grid_thw);
                            let second_per_grid = vec![
                                self.vision_setting.temporal_patch_size
                                    as f32
                                    / self.vision_setting.fps;
                                video_num
                            ];
                            second_per_grid_ts = Some(second_per_grid);
                        }
                        Err(e) => println!("video process_videos err: {:?}", e),
                    };
                }
            }
        }
        let merge_length = self.vision_setting.merge_size.pow(2);
        let mut text = text.to_string();
        if let Some(ref image_grid_thw) = image_grid_thw {
            let mut index = 0;
            while text.contains(&self.image_token) {
                let grid_i = image_grid_thw.i(index)?;
                let repeat_num =
                    grid_i.to_vec1::<u32>()?.iter().product::<u32>() as usize / merge_length;
                let replace = "<|placeholder|>".repeat(repeat_num);
                text = text.replacen(&self.image_token, &replace, 1);
                index += 1;
            }
            text = text.replace("<|placeholder|>", &self.image_token);
        }
        #[cfg(feature = "ffmpeg")]
        if let Some(ref video_grid_thw) = video_grid_thw {
            let mut index = 0;
            while text.contains(&self.video_token) {
                let grid_i = video_grid_thw.i(index)?;
                let repeat_num =
                    grid_i.to_vec1::<u32>()?.iter().product::<u32>() as usize / merge_length;
                let replace = "<|placeholder|>".repeat(repeat_num);
                text = text.replacen(&self.video_token, &replace, 1);
                index += 1;
            }
            text = text.replace("<|placeholder|>", &self.video_token);
        }
        let input = GeneralInput {
            replace_text: text,
            pixel_values,
            image_grid_thw,
            pixel_values_video,
            video_grid_thw,
            second_per_grid_ts,
        };
        Ok(input)
    }
}

pub fn smart_resize(
    img_h: u32,
    img_w: u32,
    vision_setting: &VisionSetting,
    is_img: bool,
    video_ratio: Option<u32>,
) -> Result<(u32, u32)> {
    if std::cmp::max(img_h, img_w) / std::cmp::min(img_h, img_w) > vision_setting.max_ratio {
        return Err(anyhow!(format!(
            "absolute aspect ratio mush be smaller than {}, got {}",
            vision_setting.max_ratio,
            std::cmp::max(img_h, img_w) / std::cmp::min(img_h, img_w)
        )));
    }
    let mut image_factor = vision_setting.image_factor;
    if let Some(ratio) = video_ratio {
        image_factor = lcm(image_factor, ratio);
    }
    let mut h_bar = std::cmp::max(image_factor, round_by_factor(img_h, image_factor));
    let mut w_bar = std::cmp::max(image_factor, round_by_factor(img_w, image_factor));

    let (min_pixels, max_pixels) = if is_img {
        (vision_setting.min_pixels, vision_setting.max_pixels)
    } else {
        (
            vision_setting.video_min_pixels,
            vision_setting.video_max_pixels,
        )
    };
    if h_bar * w_bar > max_pixels {
        let beta = ((img_h * img_w) as f32 / max_pixels as f32).sqrt();
        h_bar = floor_by_factor(img_h as f32 / beta, image_factor);
        w_bar = floor_by_factor(img_w as f32 / beta, image_factor);
    } else if h_bar * w_bar < min_pixels {
        let beta = (min_pixels as f32 / (img_h * img_w) as f32).sqrt();
        h_bar = ceil_by_factor(img_h as f32 * beta, image_factor);
        w_bar = ceil_by_factor(img_w as f32 * beta, image_factor);
    }
    Ok((h_bar, w_bar))
}

#[cfg(feature = "ffmpeg")]
pub fn get_video_data(
    file: &String,
    vision_setting: &VisionSetting,
    device: &Device,
) -> Result<Tensor> {
    ffmpeg::init().map_err(|e| anyhow!(format!("Failed to initialize ffmpeg: {}", e)))?;

    let mut ictx = ffmpeg::format::input(&file)
        .map_err(|e| anyhow!(format!("Failed to open video file: {}", e)))?;
    let input = ictx
        .streams()
        .best(ffmpeg::media::Type::Video)
        .ok_or_else(|| anyhow!(format!("No video stream found")))?;
    let video_stream_index = input.index();
    let context_decoder = ffmpeg::codec::context::Context::from_parameters(input.parameters())
        .map_err(|e| anyhow!(format!("Failed to crate decoder context: {}", e)))?;
    let mut decoder = context_decoder
        .decoder()
        .video()
        .map_err(|e| anyhow!(format!("Failed to decoder video: {}", e)))?;

    let video_h = decoder.height();
    let video_w = decoder.width();
    let format = decoder.format();

    let frames = input.frames();
    let rate = (input.rate().0 as f32 / input.rate().1 as f32).round() as u32;
    // 1s取两帧
    let min_frames = ceil_by_factor(
        vision_setting.fps_min_frames as f32,
        vision_setting.frame_factor,
    );
    let max_frames = floor_by_factor(
        vision_setting.fps_max_frames as f32,
        vision_setting.frame_factor,
    );
    let nframes = (frames as f32 / rate as f32 * vision_setting.fps) as u32;
    let nframes = std::cmp::min(std::cmp::max(nframes, min_frames), max_frames);
    let nframes = round_by_factor(nframes, vision_setting.frame_factor);
    let sample_interval = (frames as f32 / nframes as f32).round() as u32;
    let mut frame_id = 0_u32;

    // 图片帧使用scaler reshape的时候需要保证宽高是16的倍数,不然reshape出来的是损坏的图片
    // 所以计算resize的目标宽高时,需要用16和image_factor的最小公倍数
    let (resize_h, resize_w) = smart_resize(video_h, video_w, vision_setting, false, Some(16))?;
    let mut scaler = ffmpeg::software::scaling::context::Context::get(
        format,
        video_w,
        video_h,
        ffmpeg::format::Pixel::RGB24,
        resize_w,
        resize_h,
        ffmpeg::software::scaling::flag::Flags::BILINEAR
            | ffmpeg::software::scaling::flag::Flags::ACCURATE_RND,
    )
    .map_err(|e| anyhow!(format!("Failed to crate scaler: {}", e)))?;

    let mut frames_vec = Vec::new();
    let mut receive_and_process_decoded_frames =
        |decoder: &mut ffmpeg::decoder::Video| -> Result<()> {
            let mut decoded = ffmpeg::frame::Video::empty();
            while decoder.receive_frame(&mut decoded).is_ok() {
                if frame_id.is_multiple_of(sample_interval) {
                    let mut rgb_frame = ffmpeg::frame::Video::empty();
                    scaler
                        .run(&decoded, &mut rgb_frame)
                        .map_err(|e| anyhow!(format!("Failed to scaler run decoded: {}", e)))?;

                    // save_file(&rgb_frame, frame_id as usize);
                    let frame_data = rgb_frame.data(0);
                    let frame_tensor = Tensor::from_slice(
                        frame_data,
                        (resize_h as usize, resize_w as usize, 3),
                        device,
                    )?
                    .permute((2, 0, 1))?;
                    frames_vec.push(frame_tensor);
                }
                frame_id += 1;
            }
            Ok(())
        };

    for (stream, packet) in ictx.packets() {
        if stream.index() == video_stream_index {
            decoder
                .send_packet(&packet)
                .map_err(|e| anyhow!(format!("Failed to send packet: {}", e)))?;
            receive_and_process_decoded_frames(&mut decoder)?;
        }
    }
    decoder
        .send_eof()
        .map_err(|e| anyhow!(format!("Failed to decoder.send_eof(): {}", e)))?;
    receive_and_process_decoded_frames(&mut decoder)?;

    if frames_vec.is_empty() {
        return Err(anyhow!("No frames extracted from video".to_string()));
    }
    // (t, c, h, w)
    let frames_tensor = Tensor::stack(&frames_vec, 0)?.contiguous()?;
    Ok(frames_tensor)
}