use anyhow::{anyhow, Context, Result};
use chrono::{DateTime, Utc};
use csv::ReaderBuilder;
use glob::glob;
use hashbrown::HashMap;
use log::{info, warn};
use rayon::prelude::*;
use serde::{Deserialize, Serialize};
use std::{
    fmt::Display,
    fs::{self, File, Metadata},
    io::{self, BufRead},
    os::unix::fs::MetadataExt,
    path::PathBuf,
};

use crate::io::pod5_infos::Pod5Info;

#[derive(Debug, Clone)]
pub struct Pod5 {
    pub path: PathBuf,
    pub pod5_type: Pod5Type,
    pub run_name: String,
    pub flowcell_name: String,
    pub file_metadata: Metadata,
}

#[derive(Debug, Clone, PartialEq)]
pub enum Pod5Type {
    Raw,
    Demuxed,
}

impl Display for Pod5Type {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        let s = match self {
            Pod5Type::Raw => "raw",
            Pod5Type::Demuxed => "demuxed",
        };
        f.write_str(s)
    }
}

#[derive(Debug, Clone)]
pub struct Pod5Config {
    pub base_dir: String,
    pub type_raw: String,
    pub type_demuxed: String,
    pub run_dir_n: u8,
    pub flowcell_dir_n: u8,
}

impl Default for Pod5Config {
    fn default() -> Self {
        Self {
            base_dir: "/data/run_data".to_string(),
            type_raw: "/pod5/".to_string(),
            type_demuxed: "/pod5_pass/".to_string(),
            run_dir_n: 0,
            flowcell_dir_n: 1,
        }
    }
}

impl Pod5 {
    pub fn from_path(path: &PathBuf, config: &Pod5Config) -> Result<Self> {
        let s = path
            .to_str()
            .context("Can't convert PathBuf to str {path:?}")?;
        let pod5_type = if s.contains(&config.type_raw) {
            Pod5Type::Raw
        } else if s.contains(&config.type_demuxed) {
            Pod5Type::Demuxed
        } else {
            return Err(anyhow!("Can't find the pod5 type {s}"));
        };

        let file_metadata = fs::metadata(path)?;

        let sr = s.replace(&config.base_dir, "");
        let components: Vec<&str> = sr.split('/').filter(|c| !c.is_empty()).collect();

        let run_name = components
            .get(config.run_dir_n as usize)
            .context("Can't get run_name")?
            .to_string();
        let flowcell_name = components
            .get(config.flowcell_dir_n as usize)
            .context("Can't get flowcell_name")?
            .to_string();

        Ok(Self {
            path: path.to_path_buf(),
            pod5_type,
            run_name,
            flowcell_name,
            file_metadata,
        })
    }
}

pub fn list_pod_files(dir: &str) -> Result<Vec<Pod5>> {
    let pattern = format!("{}/**/*.pod5", dir);
    let mut pod_files = Vec::new();

    let conf = Pod5Config {
        base_dir: if dir.ends_with('/') {
            dir.to_string()
        } else {
            format!("{dir}/")
        },
        ..Pod5Config::default()
    };

    for entry in glob(&pattern).expect("Failed to read glob pattern") {
        match entry {
            Ok(path) => {
                let p = path.to_str().context("Can't parse path to string {path}")?;
                if p.contains("/pod5_fail/") || p.contains("/pod5_skip/") {
                    continue;
                }
                match Pod5::from_path(&path, &conf) {
                    Ok(pod5) => pod_files.push(pod5),
                    Err(e) => warn!("{e}"),
                }
            }
            Err(e) => warn!("Error: {:?}", e),
        }
    }
    Ok(pod_files)
}

#[derive(Debug)]
pub struct Run {
    pub run_name: String,
    pub flowcells: Vec<FlowCell>,
}

#[derive(Debug, Clone)]
pub struct FlowCell {
    pub flowcell_name: String,
    pub corrected_name: String,
    pub cases: Vec<FlowCellCase>,
    pub run_name: String,
    pub pod5_type: Pod5Type,
    pub pod5_info: Pod5Info,
    pub pod5: Vec<Pod5>,
}

// impl FlowCell {
//     pub fn cases_pod5_dir(&self) -> Vec<PathBuf> {
//         match self.pod5_type {
//             Pod5Type::Raw => {
//                 let p = self.pod5.first().unwrap();
//                 vec![p.path.parent().unwrap().to_path_buf()]
//             },
//             Pod5Type::Demuxed => {
//                 self.cases.iter().map(|c| {
//                     let str_barcode = format!("barcode{}", c.barcode);
//                 })
//             },
//         }
//     }
// }

#[derive(Debug, Default)]
pub struct Pod5Collection {
    pub importation_date: DateTime<Utc>,
    pub runs: Vec<Run>,
    pub bam_dir: String,
    pub pod5_dir: String,
}

#[derive(Debug, Clone, Default)]
pub struct FlowCellCase {
    pub id: String,
    pub time_point: String,
    pub barcode: String,
    pub pod_dir: PathBuf,
    // pub basecalled: Option<bool>,
}

impl Pod5Collection {
    pub fn new(pod5_dir: &str, corrected_fc_path: &str, bam_dir: &str) -> Result<Self> {
        let pod5 = list_pod_files(pod5_dir)?;
        info!("n pod5 {}", pod5.len());

        let mut fc: HashMap<String, Vec<Pod5>> = HashMap::new();
        for pod in pod5 {
            let k = format!("{}-{}", pod.run_name, pod.flowcell_name);
            fc.entry(k).or_default().push(pod);
        }

        let corrected_fc = load_flowcells_corrected_names(corrected_fc_path)?;
        let flow_cells: Vec<FlowCell> = fc
            .par_values()
            .map(|v| {
                let first = &v[0];
                let pod5_info = Pod5Info::from_pod5(first.path.to_str().unwrap());
                let flowcell_name = first.flowcell_name.clone();

                let sel: Vec<FCLine> = corrected_fc
                    .iter()
                    .filter(|e| e.flow_cell == flowcell_name)
                    .cloned()
                    .collect();

                let mut corrected_name: Vec<String> = sel
                    .clone()
                    .into_iter()
                    .map(|e| e.ref_flow_cell)
                    .filter(|e| !e.is_empty())
                    .collect();
                corrected_name.dedup();

                if corrected_name.len() > 1 {
                    panic!("Multiple corrected flow_cells for {v:?}");
                }

                let corrected_name = if !corrected_name.is_empty() {
                    corrected_name.first().unwrap().to_string()
                } else {
                    "".to_string()
                };

                let cases: Vec<FlowCellCase> = sel
                    .iter()
                    .map(|e| {
                        let pod_dir = match first.pod5_type {
                            Pod5Type::Raw => first.path.parent().unwrap().to_path_buf(),
                            Pod5Type::Demuxed => {
                                let mut bc_dir =
                                    first.path.parent().unwrap().parent().unwrap().to_path_buf();
                                bc_dir
                                    .push(format!("barcode{}", e.barcode_number.replace("NB", "")));
                                bc_dir
                            }
                        };

                        FlowCellCase {
                            id: e.id.clone(),
                            time_point: e.time_point.clone(),
                            barcode: e.barcode_number.clone(),
                            pod_dir,
                        }
                    })
                    .collect();

                FlowCell {
                    flowcell_name,
                    corrected_name,
                    cases,
                    run_name: first.run_name.clone(),
                    pod5_type: first.pod5_type.clone(),
                    pod5_info,
                    pod5: v.to_vec(),
                }
            })
            .collect();

        let mut runs = HashMap::new();
        for fc in flow_cells {
            runs.entry(fc.run_name.clone())
                .or_insert_with(Vec::new)
                .push(fc);
        }

        let runs: Vec<Run> = runs
            .into_values()
            .map(|v| Run {
                run_name: v[0].run_name.clone(),
                flowcells: v.to_vec(),
            })
            .collect();

        Ok(Self {
            importation_date: Utc::now(),
            runs,
            bam_dir: bam_dir.to_string(),
            pod5_dir: pod5_dir.to_string(),
        })
    }

    pub fn print_info(&self) {
        self.runs.iter().for_each(|run| {
            run.flowcells.iter().for_each(|fc| {
                let total_size: u64 = fc.pod5.iter().map(|p| p.file_metadata.size()).sum();
                let n_files = fc.pod5.len();
                let dates: Vec<DateTime<Utc>> = fc
                    .pod5
                    .iter()
                    .map(|p| p.file_metadata.modified().unwrap().into())
                    .collect();
                let from = dates.iter().min().unwrap();
                let to = dates.iter().max().unwrap();
                let s = [
                    run.run_name.clone(),
                    from.to_string(),
                    to.to_string(),
                    n_files.to_string(),
                    total_size.to_string(),
                    fc.flowcell_name.to_string(),
                    fc.pod5_type.to_string(),
                    fc.pod5_info.acquisition_id.clone(),
                    format!("{:?}", fc.cases),
                ]
                .join("\t");
                println!("{s}");
            });
        });
    }

    // pub fn check_local(&self) -> anyhow::Result<()> {
    //     let mut res = Vec::new();
    //     for run in self.runs.iter() {
    //         for fc in run.flowcells.iter() {
    //             for c in fc.cases.iter() {
    //                 let bases_called = if let Some(b) = c.basecalled {
    //                     if b {
    //                         "✅".to_string()
    //                     } else {
    //                         "❌".to_string()
    //                     }
    //                 } else {
    //                     "❌".to_string()
    //                 };
    //
    //                 let s = [
    //                     c.id.to_string(),
    //                     c.time_point.to_string(),
    //                     c.barcode.to_string(),
    //                     run.run_name.clone(),
    //                     fc.flowcell_name.to_string(),
    //                     fc.pod5_type.to_string(),
    //                     fc.pod5_info.acquisition_id.clone(),
    //                     bases_called,
    //                 ]
    //                 .join("\t");
    //                 res.push(s);
    //             }
    //         }
    //     }
    //     res.sort();
    //     println!("{}", res.join("\n"));
    //     Ok(())
    // }

    // pub fn fc_done(&self) {
    //     for run in self.runs.iter() {
    //         for fc in run.flowcells.iter() {
    //             let n_called = fc
    //                 .cases
    //                 .iter()
    //                 .filter(|c| if let Some(b) = c.basecalled { b } else { false })
    //                 .count();
    //             if n_called != 0 && n_called == fc.cases.len() {
    //                 let s = [
    //                     format!("{}/{}", run.run_name, fc.flowcell_name),
    //                     fc.pod5_info.acquisition_id.to_string(),
    //                     format!("{:#?}", fc.cases),
    //                 ]
    //                 .join("\t");
    //                 println!("{s}");
    //             }
    //         }
    //     }
    // }

    // pub fn todo(&self) {
    //     let run_dir = &self.pod5_dir;
    //     for run in self.runs.iter() {
    //         for fc in run.flowcells.iter() {
    //             let to_call: Vec<_> = fc
    //                 .cases
    //                 .iter()
    //                 .filter(|c| if let Some(b) = c.basecalled { !b } else { true })
    //                 .collect();
    //
    //             if !to_call.is_empty() {
    //                 if fc.pod5_type == Pod5Type::Raw && to_call.len() != fc.cases.len() {
    //                     println!("No solution for: {}/{}", run.run_name, fc.flowcell_name);
    //                 } else {
    //                     match fc.pod5_type {
    //                         Pod5Type::Raw => {
    //                             let cases: Vec<String> = to_call
    //                                 .iter()
    //                                 .map(|c| {
    //                                     let bc = c.barcode.replace("NB", "");
    //                                     let tp = c.time_point.to_lowercase();
    //                                     [bc, c.id.to_string(), tp].join(" ")
    //                                 })
    //                                 .collect();
    //                             println!(
    //                                 "from_mux.sh {}/{}/{} {}",
    //                                 run_dir,
    //                                 run.run_name,
    //                                 fc.flowcell_name,
    //                                 cases.join(" ")
    //                             );
    //                         }
    //                         Pod5Type::Demuxed => to_call.iter().for_each(|c| {
    //                             let bc = c.barcode.replace("NB", "");
    //                             let tp = c.time_point.to_lowercase();
    //                             let bam = format!(
    //                                 "{}/{}/{}/{}_{}_hs1.bam",
    //                                 self.bam_dir, c.id, c.time_point, c.id, c.time_point
    //                             );
    //                             if PathBuf::from(bam).exists() {
    //                                 let pod_dir: Vec<String> = fc
    //                                     .pod5
    //                                     .iter()
    //                                     .filter(|p| {
    //                                         p.path.contains(&format!("barcode{}", bc.clone()))
    //                                     })
    //                                     .take(1)
    //                                     .map(|p| p.path.to_string())
    //                                     .collect();
    //
    //                                 let pod_dir = pod_dir.first().unwrap();
    //                                 let mut pod_dir = PathBuf::from(pod_dir);
    //                                 pod_dir.pop();
    //
    //                                 // TODO sheduler
    //                                 println!(
    //                                     "complete_bam.sh {} {} {}",
    //                                     c.id,
    //                                     tp,
    //                                     pod_dir.to_string_lossy()
    //                                 )
    //                             } else {
    //                                 let pod_dir: Vec<String> = fc
    //                                     .pod5
    //                                     .iter()
    //                                     .filter(|p| {
    //                                         p.path.contains(&format!("barcode{}", bc.clone()))
    //                                     })
    //                                     .take(1)
    //                                     .map(|p| p.path.to_string())
    //                                     .collect();
    //
    //                                 let pod_dir = pod_dir.first().unwrap();
    //                                 let mut pod_dir = PathBuf::from(pod_dir);
    //                                 pod_dir.pop();
    //
    //                                 println!(
    //                                     "dorado.sh {} {} {}",
    //                                     c.id,
    //                                     tp,
    //                                     pod_dir.to_string_lossy()
    //                                 )
    //                             }
    //                         }),
    //                     };
    //                 }
    //             }
    //         }
    //     }
    // }

    pub fn ids(&self) -> Vec<String> {
        let mut ids: Vec<String> = self
            .runs
            .iter()
            .flat_map(|r| {
                r.flowcells
                    .iter()
                    .flat_map(|f| {
                        f.cases
                            .iter()
                            .map(|c| c.id.clone())
                            .collect::<Vec<String>>()
                    })
                    .collect::<Vec<String>>()
            })
            .collect();
        ids.sort();
        ids.dedup();
        ids
    }
}

#[derive(Debug, Deserialize, Clone)]
pub struct FCLine {
    pub id: String,
    pub time_point: String,
    pub barcode_number: String,
    pub flow_cell: String,
    pub run: String,
    pub path: String,
    pub ref_flow_cell: String,
}

pub fn load_flowcells_corrected_names(file_path: &str) -> anyhow::Result<Vec<FCLine>> {
    let file = File::open(file_path)?;

    let mut rdr = ReaderBuilder::new()
        .delimiter(b'\t')
        .has_headers(true)
        .from_reader(file);

    let mut records = Vec::new();
    for result in rdr.deserialize() {
        let mut record: FCLine = result?;

        // formating
        record.time_point = record.time_point.to_lowercase();
        record.id = record.id.to_uppercase();

        records.push(record);
    }

    Ok(records)
}

#[derive(Debug, Serialize, Deserialize)]
struct MinKnowSampleSheet {
    pub protocol_run_id: String,
    pub position_id: String,
    pub flow_cell_id: String,
    pub sample_id: String,
    pub experiment_id: String,
    pub flow_cell_product_code: String,
    pub kit: String,
}

impl TryFrom<&str> for MinKnowSampleSheet {
    type Error = anyhow::Error;

    fn try_from(value: &str) -> anyhow::Result<Self> {
        let cells: Vec<&str> = value.split(",").collect();
        if cells.len() != 7 {
            return Err(anyhow::anyhow!(
                "Number of cells not equal to definition. {value}"
            ));
        }

        Ok(Self {
            protocol_run_id: cells[0].to_string(),
            position_id: cells[1].to_string(),
            flow_cell_id: cells[2].to_string(),
            sample_id: cells[3].to_string(),
            experiment_id: cells[4].to_string(),
            flow_cell_product_code: cells[5].to_string(),
            kit: cells[6].to_string(),
        })
    }
}

impl MinKnowSampleSheet {
    pub fn from_path(path: &str) -> anyhow::Result<Self> {
        let file = File::open(path).map_err(|e| format!("Can't open file: {path}\n{e}"))?;
        let reader = io::BufReader::new(file);
        for (i, line) in reader.lines().enumerate() {
            let line = line.map_err(|e| format!("Error parsing line: {line:?}\n\t{e}"))?;
            if i == 0 && line != "protocol_run_id,position_id,flow_cell_id,sample_id,experiment_id,flow_cell_product_code,kit" {
                return Err(anyhow::anyhow!("File header doesnt correspond to MinKnwo sample sheet: {line}"));
            } else if i == 1 {
                return Ok(line.as_str().try_into()?);
            } else {
                return Err(anyhow::anyhow!("Wrong MinKnow sample sheet format."));
            }
        }
                        return Err(anyhow::anyhow!("Wrong MinKnow sample sheet format."));

    }
}