use crate::{common::MaybeLock, get_proxy_envs_for_lang};
use windmill_common::scripts::ScriptLang;
use std::{collections::HashMap, fs::DirBuilder, process::Stdio};

use itertools::Itertools;
use serde_json::value::RawValue;
use tokio::{
    fs::{self, File},
    io::AsyncReadExt,
    process::Command,
};
use uuid::Uuid;
use windmill_common::{
    error::{self, Error},
    utils::calculate_hash,
    worker::{save_cache, write_file, Connection, GoAnnotations},
};
use windmill_parser_go::{parse_go_imports, REQUIRE_PARSE};
use windmill_queue::{append_logs, CanceledBy, MiniPulledJob};

use crate::{
    common::{
        build_command_with_isolation, capitalize, create_args_and_out_file, get_reserved_variables,
        read_result, start_child_process, OccupancyMetrics, DEV_CONF_NSJAIL,
    },
    handle_child::handle_child,
    DISABLE_NSJAIL, DISABLE_NUSER, GOPRIVATE, GOPROXY, GO_BIN_CACHE_DIR, GO_CACHE_DIR, HOME_ENV,
    NSJAIL_PATH, PATH_ENV, PROXY_ENVS, TRACING_PROXY_CA_CERT_PATH, TZ_ENV,
};
use windmill_common::client::AuthedClient;

#[cfg(windows)]
use crate::SYSTEM_ROOT;

#[cfg(windows)]
fn get_windows_tmp_dir() -> String {
    std::env::var("TMP")
        .or_else(|_| std::env::var("TEMP"))
        .unwrap_or_else(|_| {
            let system_drive = std::env::var("SYSTEMDRIVE").unwrap_or_else(|_| "C:".to_string());
            format!("{}\\tmp", system_drive)
        })
}

#[cfg(windows)]
fn get_windows_program_files() -> String {
    std::env::var("ProgramFiles").unwrap_or_else(|_| {
        let system_drive = std::env::var("SYSTEMDRIVE").unwrap_or_else(|_| "C:".to_string());
        format!("{}\\Program Files", system_drive)
    })
}

#[cfg(windows)]
fn windows_gopath() -> String {
    let tmp_dir = get_windows_tmp_dir();
    GO_CACHE_DIR.replace("/tmp", &tmp_dir).replace("/", r"\\")
}

#[cfg(windows)]
fn set_windows_env_vars(cmd: &mut Command) {
    cmd.env("SystemRoot", SYSTEM_ROOT.as_str())
        .env("TMP", get_windows_tmp_dir())
        .env("USERPROFILE", crate::USERPROFILE_ENV.as_str())
        .env(
            "APPDATA",
            std::env::var("APPDATA")
                .unwrap_or_else(|_| format!("{}\\AppData\\Roaming", HOME_ENV.as_str())),
        )
        .env("ProgramFiles", get_windows_program_files())
        .env(
            "LOCALAPPDATA",
            std::env::var("LOCALAPPDATA")
                .unwrap_or_else(|_| format!("{}\\AppData\\Local", HOME_ENV.as_str())),
        );
}

const GO_REQ_SPLITTER: &str = "//go.sum\n";
const NSJAIL_CONFIG_RUN_GO_CONTENT: &str = include_str!("../nsjail/run.go.config.proto");

lazy_static::lazy_static! {
    static ref GO_PATH: String = std::env::var("GO_PATH").unwrap_or_else(|_| "/usr/bin/go".to_string());
}

pub const GO_OBJECT_STORE_PREFIX: &str = "gobin/";
#[tracing::instrument(level = "trace", skip_all)]
pub async fn handle_go_job(
    mem_peak: &mut i32,
    canceled_by: &mut Option<CanceledBy>,
    job: &MiniPulledJob,
    conn: &Connection,
    client: &AuthedClient,
    parent_runnable_path: Option<String>,
    inner_content: &str,
    job_dir: &str,
    shared_mount: &str,
    base_internal_url: &str,
    worker_name: &str,
    envs: HashMap<String, String>,
    occupation_metrics: &mut OccupancyMetrics,
    maybe_lock: MaybeLock,
) -> Result<Box<RawValue>, Error> {
    //go does not like executing modules at temp root
    let job_dir = &format!("{job_dir}/go");
    DirBuilder::new()
        .recursive(true)
        .create(&job_dir)
        .expect("could not create go job dir");

    let hash = calculate_hash(&format!("{}{:?}v2", inner_content, &maybe_lock));
    let bin_path = format!("{}/{hash}", GO_BIN_CACHE_DIR);
    let remote_path = format!("{GO_OBJECT_STORE_PREFIX}{hash}");
    let (cache, cache_logs) =
        windmill_common::worker::load_cache(&bin_path, &remote_path, false).await;

    let (skip_go_mod, skip_tidy) = if cache {
        (true, true)
    } else if let Some(lock) = maybe_lock.get_lock() {
        gen_go_mod(inner_content, job_dir, &lock).await?
    } else {
        (false, false)
    };

    let cache_logs = if !cache {
        let logs1 = format!("{cache_logs}\n\n--- GO DEPENDENCIES SETUP ---\n");
        append_logs(&job.id, &job.workspace_id, logs1, conn).await;

        install_go_dependencies(
            &job.id,
            inner_content,
            maybe_lock,
            mem_peak,
            canceled_by,
            job_dir,
            conn,
            true,
            skip_go_mod,
            skip_tidy,
            worker_name,
            &job.workspace_id,
            occupation_metrics,
        )
        .await?;

        create_args_and_out_file(client, job, job_dir, conn).await?;
        {
            let sig = windmill_parser_go::parse_go_sig(&inner_content)?;

            const WRAPPER_CONTENT: &str = r#"package main

import (
    "encoding/json"
    "os"
    "fmt"
    "mymod/inner"
)

func main() {{

    dat, err := os.ReadFile("args.json")
    if err != nil {{
        fmt.Println(err)
        os.Exit(1)
    }}

    var req inner.Req

    if err := json.Unmarshal(dat, &req); err != nil {{
        fmt.Println(err)
        os.Exit(1)
    }}

    res, err := inner.Run(req)
    if err != nil {{
        fmt.Println(err)
        os.Exit(1)
    }}
    res_json, err := json.Marshal(res)
    if err != nil {{
        fmt.Println(err)
        os.Exit(1)
    }}
    f, err := os.OpenFile("result.json", os.O_APPEND|os.O_WRONLY, os.ModeAppend)
    if err != nil {{
        fmt.Println(err)
        os.Exit(1)
    }}
    _, err = f.WriteString(string(res_json))
    if err != nil {{
        fmt.Println(err)
        os.Exit(1)
    }}
}}"#;

            write_file(job_dir, "main.go", WRAPPER_CONTENT)?;

            {
                let spread = &sig
                    .args
                    .clone()
                    .into_iter()
                    .map(|x| format!("req.{}", capitalize(&x.name)))
                    .join(", ");
                let req_body = &sig
                    .args
                    .into_iter()
                    .map(|x| {
                        format!(
                            "{} {} `json:\"{}\"`",
                            capitalize(&x.name),
                            windmill_parser_go::otyp_to_string(x.otyp),
                            x.name
                        )
                    })
                    .join("\n");
                let runner_content: String = format!(
                    r#"package inner
type Req struct {{
    {req_body}
}}

func Run(req Req) (interface{{}}, error){{
    return main({spread})
}}

"#,
                );
                write_file(&format!("{job_dir}/inner"), "runner.go", &runner_content)?;
            }
        }

        let mut build_go_cmd = Command::new(GO_PATH.as_str());
        build_go_cmd
            .current_dir(job_dir)
            .env_clear()
            .env("PATH", PATH_ENV.as_str())
            .env("BASE_INTERNAL_URL", base_internal_url)
            .env("GOPATH", {
                #[cfg(unix)]
                {
                    GO_CACHE_DIR
                }
                #[cfg(windows)]
                {
                    windows_gopath()
                }
            })
            .env("HOME", HOME_ENV.as_str())
            .env("GOCACHE", GO_CACHE_DIR)
            .envs(PROXY_ENVS.clone())
            .args(vec!["build", "main.go"])
            .stdout(Stdio::piped())
            .stderr(Stdio::piped());

        #[cfg(windows)]
        set_windows_env_vars(&mut build_go_cmd);

        let build_go_process = start_child_process(build_go_cmd, GO_PATH.as_str(), false).await?;
        handle_child(
            &job.id,
            conn,
            mem_peak,
            canceled_by,
            build_go_process,
            false,
            worker_name,
            &job.workspace_id,
            "go build",
            None,
            false,
            &mut Some(occupation_metrics),
            None,
            None,
        )
        .await?;

        #[cfg(unix)]
        let executable_path = format!("{job_dir}/main");
        #[cfg(windows)]
        let executable_path = format!("{job_dir}/main.exe");

        // Set executable permissions on Windows
        #[cfg(windows)]
        {
            use std::fs;
            if let Ok(metadata) = fs::metadata(&executable_path) {
                let mut permissions = metadata.permissions();
                permissions.set_readonly(false);
                // On Windows, we need to ensure the file is not marked as read-only
                // and has appropriate permissions for execution
                let _ = fs::set_permissions(&executable_path, permissions);
            }
        }

        match save_cache(
            &bin_path,
            &format!("{GO_OBJECT_STORE_PREFIX}{hash}"),
            &executable_path,
            false,
        )
        .await
        {
            Err(e) => {
                let em = format!("could not save {bin_path} to go cache: {e:?}");
                tracing::error!(em);
                em
            }
            Ok(logs) => logs,
        }
    } else {
        #[cfg(unix)]
        let target = format!("{job_dir}/main");
        #[cfg(windows)]
        let target = format!("{job_dir}/main.exe");

        #[cfg(unix)]
        let symlink = std::os::unix::fs::symlink(&bin_path, &target);
        #[cfg(windows)]
        let symlink = {
            // On Windows, copy the file instead of creating a symlink
            // because symlinks might not work correctly for executables
            use std::fs;
            fs::copy(&bin_path, &target).map(|_| ())
        };

        symlink.map_err(|e| {
            Error::ExecutionErr(format!(
                "could not copy cached binary from {bin_path} to {job_dir}/main: {e:?}"
            ))
        })?;

        create_args_and_out_file(client, job, job_dir, conn).await?;
        cache_logs
    };

    let logs2 = format!("{cache_logs}\n\n--- GO CODE EXECUTION ---\n");
    append_logs(&job.id, &job.workspace_id, logs2, conn).await;

    let reserved_variables =
        get_reserved_variables(job, &client.token, conn, parent_runnable_path).await?;

    let child = if !*DISABLE_NSJAIL {
        let _ = write_file(
            job_dir,
            "run.config.proto",
            &NSJAIL_CONFIG_RUN_GO_CONTENT
                .replace("{JOB_DIR}", job_dir)
                .replace("{CLONE_NEWUSER}", &(!*DISABLE_NUSER).to_string())
                .replace("{SHARED_MOUNT}", shared_mount)
                .replace("{TRACING_PROXY_CA_CERT_PATH}", TRACING_PROXY_CA_CERT_PATH)
                .replace("#{DEV}", DEV_CONF_NSJAIL),
        )?;
        let mut nsjail_cmd = Command::new(NSJAIL_PATH.as_str());
        nsjail_cmd
            .current_dir(job_dir)
            .env_clear()
            .envs(envs)
            .envs(reserved_variables)
            .envs(get_proxy_envs_for_lang(&ScriptLang::Go).await?)
            .env("PATH", PATH_ENV.as_str())
            .env("TZ", TZ_ENV.as_str())
            .env("BASE_INTERNAL_URL", base_internal_url)
            .args(vec!["--config", "run.config.proto", "--", "/tmp/go/main"])
            .stdout(Stdio::piped())
            .stderr(Stdio::piped());
        start_child_process(nsjail_cmd, NSJAIL_PATH.as_str(), false).await?
    } else {
        #[cfg(unix)]
        let compiled_executable_name = "./main";
        #[cfg(windows)]
        let compiled_executable_name = format!("{}/main.exe", job_dir);

        let mut run_go = build_command_with_isolation(&compiled_executable_name, &[]);

        run_go
            .current_dir(job_dir)
            .env_clear()
            .envs(envs)
            .envs(reserved_variables)
            .envs(get_proxy_envs_for_lang(&ScriptLang::Go).await?)
            .env("PATH", PATH_ENV.as_str())
            .env("TZ", TZ_ENV.as_str())
            .env("BASE_INTERNAL_URL", base_internal_url)
            .env("GOPATH", {
                #[cfg(unix)]
                {
                    GO_CACHE_DIR
                }
                #[cfg(windows)]
                {
                    windows_gopath()
                }
            })
            .env("HOME", HOME_ENV.as_str());

        if let Some(ref goprivate) = *GOPRIVATE {
            run_go.env("GOPRIVATE", goprivate);
        }
        if let Some(ref goproxy) = *GOPROXY {
            run_go.env("GOPROXY", goproxy);
        }

        #[cfg(windows)]
        set_windows_env_vars(&mut run_go);

        run_go
            .stdin(Stdio::null())
            .stdout(Stdio::piped())
            .stderr(Stdio::piped());
        start_child_process(run_go, &compiled_executable_name, false).await?
    };
    let handle_result = handle_child(
        &job.id,
        conn,
        mem_peak,
        canceled_by,
        child,
        !*DISABLE_NSJAIL,
        worker_name,
        &job.workspace_id,
        "go run",
        job.timeout,
        false,
        &mut Some(occupation_metrics),
        None,
        None,
    )
    .await?;

    read_result(job_dir, handle_result.result_stream).await
}

async fn gen_go_mod(inner_content: &str, job_dir: &str, lock: &str) -> error::Result<(bool, bool)> {
    gen_go_mymod(inner_content, job_dir).await?;

    let md = lock.split_once(GO_REQ_SPLITTER);
    if let Some((req, sum)) = md {
        write_file(job_dir, "go.mod", &req)?;
        write_file(job_dir, "go.sum", &sum)?;
        Ok((true, true))
    } else {
        write_file(job_dir, "go.mod", &lock)?;
        Ok((true, false))
    }
}

use std::fs::OpenOptions;
use std::io::prelude::*;

pub async fn install_go_dependencies(
    job_id: &Uuid,
    code: &str,
    maybe_lock: MaybeLock,
    mem_peak: &mut i32,
    canceled_by: &mut Option<CanceledBy>,
    job_dir: &str,
    conn: &Connection,
    non_dep_job: bool,
    // NOTE: this is impossible for skip_go_mod be `false` and maybe_lock be `Resolved`.
    // TODO: make it comptime gurantee
    skip_go_mod: bool,
    has_sum: bool,
    worker_name: &str,
    w_id: &str,
    occupation_metrics: &mut OccupancyMetrics,
) -> error::Result<String> {
    let anns = GoAnnotations::parse(code);

    let hash_input = match maybe_lock {
        MaybeLock::Resolved { ref lock } => lock.clone(),
        MaybeLock::Unresolved { ref workspace_dependencies } => {
            // NOTE: This will always be none, go workspace dependencies are disabled for now.
            // read more on discord (internal):
            // https://discord.com/channels/930051556043276338/1031563866641018910/1443541229349634189
            if let Some(go_mod) = workspace_dependencies.get_go()? {
                if !skip_go_mod {
                    gen_go_mymod(code, job_dir).await?;
                    fs::write(format!("{job_dir}/go.mod"), &go_mod).await?;
                }
                go_mod
            } else {
                if !skip_go_mod {
                    gen_go_mymod(code, job_dir).await?;
                    let mut child_cmd = Command::new(GO_PATH.as_str());
                    child_cmd
                        .current_dir(job_dir)
                        .env_clear()
                        .args(vec!["mod", "init", "mymod"])
                        .stdout(Stdio::piped())
                        .stderr(Stdio::piped());

                    #[cfg(windows)]
                    child_cmd.env("GOPATH", windows_gopath());
                    #[cfg(unix)]
                    child_cmd.env("GOPATH", GO_CACHE_DIR);

                    #[cfg(windows)]
                    set_windows_env_vars(&mut child_cmd);
                    let child_process =
                        start_child_process(child_cmd, GO_PATH.as_str(), false).await?;

                    handle_child(
                        job_id,
                        conn,
                        mem_peak,
                        canceled_by,
                        child_process,
                        false,
                        worker_name,
                        w_id,
                        "go init",
                        None,
                        false,
                        &mut Some(occupation_metrics),
                        None,
                        None,
                    )
                    .await?;

                    for x in REQUIRE_PARSE.captures_iter(code) {
                        let mut file = OpenOptions::new()
                            .write(true)
                            .append(true)
                            .open(format!("{job_dir}/go.mod"))
                            .unwrap();

                        writeln!(file, "require {}\n", &x[1])?;
                    }
                }
                if !has_sum {
                    calculate_hash(parse_go_imports(&code)?.iter().join("\n").as_str())
                } else {
                    "".to_owned()
                }
            }
        }
    };

    let hash = format!(
        "go{}-{}",
        if anns.go1_22_compat { "1.22" } else { "" },
        calculate_hash(&hash_input)
    );

    let (mut new_lockfile, mut skip_tidy) = (false, has_sum);

    if !has_sum {
        if let Some(db) = conn.as_sql() {
            if let Some(cached) = sqlx::query_scalar!(
                "SELECT lockfile FROM pip_resolution_cache WHERE hash = $1",
                hash
            )
            .fetch_optional(db)
            .await?
            {
                let logs1 = format!("\nfound cached resolution: {}", hash);
                append_logs(&job_id, w_id, logs1, conn).await;
                gen_go_mod(code, job_dir, &cached).await?;
                skip_tidy = true;
                new_lockfile = false;
            } else {
                new_lockfile = true;
            }
        }
    }

    let mod_command = if skip_tidy { "download" } else { "tidy" };
    let mut child_cmd = Command::new(GO_PATH.as_str());
    child_cmd
        .current_dir(job_dir)
        .env_clear()
        .env("HOME", HOME_ENV.as_str())
        .env("PATH", PATH_ENV.as_str())
        .env("GOPATH", {
            #[cfg(unix)]
            {
                GO_CACHE_DIR
            }
            #[cfg(windows)]
            {
                windows_gopath()
            }
        })
        .args(vec!["mod", mod_command])
        .stdout(Stdio::piped())
        .stderr(Stdio::piped());

    if let Some(ref goprivate) = *GOPRIVATE {
        child_cmd.env("GOPRIVATE", goprivate);
    }

    // TODO: Remove if no incidents reported
    if !std::env::var("WMDEBUG_NO_GOPROXY_ON_TIDY").ok().is_some() {
        if let Some(ref goproxy) = *GOPROXY {
            child_cmd.env("GOPROXY", goproxy);
        }
    }

    // If annotation used we want to call tidy with special flag to pin go to 1.22
    // The reason for this that at some point we had to jump from go 1.22 to 1.25 and this addds backward compatibility.
    if anns.go1_22_compat && mod_command == "tidy" {
        child_cmd.args(vec!["-go", "1.22"]);
    }

    #[cfg(windows)]
    set_windows_env_vars(&mut child_cmd);
    let child_process = start_child_process(child_cmd, GO_PATH.as_str(), false).await?;

    handle_child(
        job_id,
        conn,
        mem_peak,
        canceled_by,
        child_process,
        false,
        worker_name,
        &w_id,
        &format!("go {mod_command}"),
        None,
        false,
        &mut Some(occupation_metrics),
        None,
        None,
    )
    .await?;

    if (!new_lockfile || has_sum) && non_dep_job {
        return Ok("".to_string());
    }

    let mut req_content = "".to_string();

    let mut file = File::open(format!("{job_dir}/go.mod")).await?;
    file.read_to_string(&mut req_content).await?;
    req_content.push_str(GO_REQ_SPLITTER);
    let sum_path = format!("{job_dir}/go.sum");
    if tokio::fs::metadata(&sum_path).await.is_ok() {
        let mut file = File::open(sum_path).await?;
        file.read_to_string(&mut req_content).await?;
    }

    if non_dep_job {
        if let Some(db) = conn.as_sql() {
            sqlx::query!(
                "INSERT INTO pip_resolution_cache (hash, lockfile, expiration) VALUES ($1, $2, now() + ('5 mins')::interval) ON CONFLICT (hash) DO UPDATE SET lockfile = EXCLUDED.lockfile",
                hash,
                req_content
            )
            .fetch_optional(db)
            .await?;
        }

        return Ok(String::new());
    } else {
        Ok(req_content)
    }
}

async fn gen_go_mymod(code: &str, job_dir: &str) -> error::Result<()> {
    let code = if code.trim_start().starts_with("package") {
        code.to_string()
    } else {
        format!("package inner; {code}")
    };

    let mymod_dir = format!("{job_dir}/inner");
    DirBuilder::new()
        .recursive(true)
        .create(&mymod_dir)
        .expect("could not create go's mymod dir");

    write_file(&mymod_dir, "inner_main.go", &code)?;

    Ok(())
}