use anyhow::{format_err, Error};
use serde_json::{json, Value};

use proxmox::{
    api::{
        api,
        cli::*,
        ApiHandler,
        RpcEnvironment,
        section_config::SectionConfigData,
    },
    tools::{
        time::strftime_local,
        io::ReadExt,
    },
};

use proxmox_backup::{
    tools::format::{
        HumanByte,
        render_epoch,
    },
    server::{
        UPID,
        worker_is_active_local,
    },
    api2::{
        self,
        types::{
            DATASTORE_SCHEMA,
            DRIVE_NAME_SCHEMA,
            MEDIA_LABEL_SCHEMA,
            MEDIA_POOL_NAME_SCHEMA,
        },
    },
    config::{
        self,
        datastore::complete_datastore_name,
        drive::complete_drive_name,
        media_pool::complete_pool_name,
    },
    tape::{
        open_drive,
        complete_media_changer_id,
        file_formats::{
            PROXMOX_BACKUP_CONTENT_HEADER_MAGIC_1_0,
            PROXMOX_BACKUP_CONTENT_NAME,
            MediaContentHeader,
        },
    },
};

mod proxmox_tape;
use proxmox_tape::*;

// Note: local workers should print logs to stdout, so there is no need
// to fetch/display logs. We just wait for the worker to finish.
pub async fn wait_for_local_worker(upid_str: &str) -> Result<(), Error> {

    let upid: UPID = upid_str.parse()?;

    let sleep_duration = core::time::Duration::new(0, 100_000_000);

    loop {
        if worker_is_active_local(&upid) {
            tokio::time::delay_for(sleep_duration).await;
        } else {
            break;
        }
    }
    Ok(())
}

fn lookup_drive_name(
    param: &Value,
    config: &SectionConfigData,
) -> Result<String, Error> {

    let drive = param["drive"]
        .as_str()
        .map(String::from)
        .or_else(|| std::env::var("PROXMOX_TAPE_DRIVE").ok())
        .or_else(||  {

            let mut drive_names = Vec::new();

            for (name, (section_type, _)) in config.sections.iter() {

                if !(section_type == "linux" || section_type == "virtual") { continue; }
                drive_names.push(name);
            }

            if drive_names.len() == 1 {
                Some(drive_names[0].to_owned())
            } else {
                None
            }
        })
        .ok_or_else(|| format_err!("unable to get (default) drive name"))?;

    Ok(drive)
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
            fast: {
                description: "Use fast erase.",
                type: bool,
                optional: true,
                default: true,
            },
        },
    },
)]
/// Erase media
async fn erase_media(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let info = &api2::tape::drive::API_METHOD_ERASE_MEDIA;

    let result = match info.handler {
        ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
        _ => unreachable!(),
    };

    wait_for_local_worker(result.as_str().unwrap()).await?;

    Ok(())
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
        },
    },
)]
/// Rewind tape
async fn rewind(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let info = &api2::tape::drive::API_METHOD_REWIND;

    let result = match info.handler {
        ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
        _ => unreachable!(),
    };

    wait_for_local_worker(result.as_str().unwrap()).await?;

    Ok(())
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
        },
    },
)]
/// Eject/Unload drive media
async fn eject_media(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let info = &api2::tape::drive::API_METHOD_EJECT_MEDIA;

    match info.handler {
        ApiHandler::Async(handler) => (handler)(param, info, rpcenv).await?,
        _ => unreachable!(),
    };

    Ok(())
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
            "changer-id": {
                schema: MEDIA_LABEL_SCHEMA,
            },
        },
    },
)]
/// Load media
async fn load_media(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let info = &api2::tape::drive::API_METHOD_LOAD_MEDIA;

    match info.handler {
        ApiHandler::Async(handler) => (handler)(param, info, rpcenv).await?,
        _ => unreachable!(),
    };

    Ok(())
}

#[api(
    input: {
        properties: {
            pool: {
                schema: MEDIA_POOL_NAME_SCHEMA,
                optional: true,
            },
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
            "changer-id": {
                schema: MEDIA_LABEL_SCHEMA,
            },
       },
    },
)]
/// Label media
async fn label_media(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let info = &api2::tape::drive::API_METHOD_LABEL_MEDIA;

    let result = match info.handler {
        ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
        _ => unreachable!(),
    };

    wait_for_local_worker(result.as_str().unwrap()).await?;

    Ok(())
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
             "output-format": {
                schema: OUTPUT_FORMAT,
                optional: true,
             },
        },
    },
)]
/// Read media label
async fn read_label(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let output_format = get_output_format(&param);
    let info = &api2::tape::drive::API_METHOD_READ_LABEL;
    let mut data = match info.handler {
        ApiHandler::Async(handler) => (handler)(param, info, rpcenv).await?,
        _ => unreachable!(),
    };

    let options = default_table_format_options()
        .column(ColumnConfig::new("changer-id"))
        .column(ColumnConfig::new("uuid"))
        .column(ColumnConfig::new("ctime").renderer(render_epoch))
        .column(ColumnConfig::new("pool"))
        .column(ColumnConfig::new("media-set-uuid"))
        .column(ColumnConfig::new("media-set-ctime").renderer(render_epoch))
        ;

    format_and_print_result_full(&mut data, &info.returns, &output_format, &options);

    Ok(())
}

#[api(
    input: {
        properties: {
            "output-format": {
                schema: OUTPUT_FORMAT,
                optional: true,
            },
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
            "read-labels": {
                description: "Load unknown tapes and try read labels",
                type: bool,
                optional: true,
            },
            "read-all-labels": {
                description: "Load all tapes and try read labels (even if already inventoried)",
                type: bool,
                optional: true,
            },
        },
    },
)]
/// List (and update) media labels (Changer Inventory)
async fn inventory(
    read_labels: Option<bool>,
    read_all_labels: Option<bool>,
    param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let output_format = get_output_format(&param);

    let (config, _digest) = config::drive::config()?;
    let drive = lookup_drive_name(&param, &config)?;

    let do_read = read_labels.unwrap_or(false) || read_all_labels.unwrap_or(false);

    if do_read {
        let mut param = json!({
            "drive": &drive,
        });
        if let Some(true) = read_all_labels {
            param["read-all-labels"] = true.into();
        }
        let info = &api2::tape::drive::API_METHOD_UPDATE_INVENTORY;
        let result = match info.handler {
            ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
            _ => unreachable!(),
        };
        wait_for_local_worker(result.as_str().unwrap()).await?;
    }

    let info = &api2::tape::drive::API_METHOD_INVENTORY;

    let param = json!({ "drive": &drive });
    let mut data = match info.handler {
        ApiHandler::Async(handler) => (handler)(param, info, rpcenv).await?,
        _ => unreachable!(),
    };

    let options = default_table_format_options()
        .column(ColumnConfig::new("changer-id"))
        .column(ColumnConfig::new("uuid"))
        ;

    format_and_print_result_full(&mut data, &info.returns, &output_format, &options);

    Ok(())
}

#[api(
    input: {
        properties: {
            pool: {
                schema: MEDIA_POOL_NAME_SCHEMA,
                optional: true,
            },
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
        },
    },
)]
/// Label media with barcodes from changer device
async fn barcode_label_media(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let info = &api2::tape::drive::API_METHOD_BARCODE_LABEL_MEDIA;

    let result = match info.handler {
        ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
        _ => unreachable!(),
    };

    wait_for_local_worker(result.as_str().unwrap()).await?;

    Ok(())
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
        },
    },
)]
/// Move to end of media (MTEOM, used to debug)
fn move_to_eom(param: Value) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    let drive = lookup_drive_name(&param, &config)?;
    let mut drive = open_drive(&config, &drive)?;

    drive.move_to_eom()?;

    Ok(())
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
        },
    },
)]
/// Rewind, then read media contents and print debug info
///
/// Note: This reads unless the driver returns an IO Error, so this
/// method is expected to fails when we reach EOT.
fn debug_scan(param: Value) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    let drive = lookup_drive_name(&param, &config)?;
    let mut drive = open_drive(&config, &drive)?;

    println!("rewinding tape");
    drive.rewind()?;

    loop {
        let file_number = drive.current_file_number()?;

        match drive.read_next_file()? {
            None => {
                println!("EOD");
                continue;
            },
            Some(mut reader) => {
                println!("got file number {}", file_number);

                let header: Result<MediaContentHeader, _> = unsafe { reader.read_le_value() };
                match header {
                    Ok(header) => {
                        if header.magic != PROXMOX_BACKUP_CONTENT_HEADER_MAGIC_1_0 {
                            println!("got MediaContentHeader with wrong magic: {:?}", header.magic);
                        } else {
                            if let Some(name) = PROXMOX_BACKUP_CONTENT_NAME.get(&header.content_magic) {
                                println!("got content header: {}", name);
                                println!("  uuid:  {}", header.content_uuid());
                                println!("  ctime: {}", strftime_local("%c", header.ctime)?);
                                println!("  hsize: {}", HumanByte::from(header.size as usize));
                                println!("  part:  {}", header.part_number);
                            } else {
                                println!("got unknown content header: {:?}", header.content_magic);
                            }
                        }
                    }
                    Err(err) => {
                        println!("unable to read content header - {}", err);
                    }
                }
                let bytes = reader.skip_to_end()?;
                println!("skipped {}", HumanByte::from(bytes));
            }
        }
    }
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
             "output-format": {
                schema: OUTPUT_FORMAT,
                optional: true,
             },
        },
    },
)]
/// Read Cartridge Memory (Medium auxiliary memory attributes)
fn cartridge_memory(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let output_format = get_output_format(&param);
    let info = &api2::tape::drive::API_METHOD_CARTRIDGE_MEMORY;

    let mut data = match info.handler {
        ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
        _ => unreachable!(),
    };

    let options = default_table_format_options()
        .column(ColumnConfig::new("id"))
        .column(ColumnConfig::new("name"))
        .column(ColumnConfig::new("value"))
        ;

    format_and_print_result_full(&mut data, &info.returns, &output_format, &options);
    Ok(())
}

#[api(
    input: {
        properties: {
            drive: {
                schema: DRIVE_NAME_SCHEMA,
                optional: true,
            },
             "output-format": {
                schema: OUTPUT_FORMAT,
                optional: true,
             },
        },
    },
)]
/// Get drive status
fn status(
    mut param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let (config, _digest) = config::drive::config()?;

    param["drive"] = lookup_drive_name(&param, &config)?.into();

    let output_format = get_output_format(&param);
    let info = &api2::tape::drive::API_METHOD_STATUS;

    let mut data = match info.handler {
        ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
        _ => unreachable!(),
    };

    let options = default_table_format_options()
        .column(ColumnConfig::new("blocksize"))
        .column(ColumnConfig::new("density"))
        .column(ColumnConfig::new("status"))
        .column(ColumnConfig::new("file-number"))
        .column(ColumnConfig::new("block-number"))
        ;

    format_and_print_result_full(&mut data, &info.returns, &output_format, &options);
    Ok(())
}

#[api(
   input: {
        properties: {
            store: {
                schema: DATASTORE_SCHEMA,
            },
            pool: {
                schema: MEDIA_POOL_NAME_SCHEMA,
            },
        },
    },
)]
/// Backup datastore to tape media pool
async fn backup(
    param: Value,
    rpcenv: &mut dyn RpcEnvironment,
) -> Result<(), Error> {

    let info = &api2::tape::backup::API_METHOD_BACKUP;

    let result = match info.handler {
        ApiHandler::Sync(handler) => (handler)(param, info, rpcenv)?,
        _ => unreachable!(),
    };

    wait_for_local_worker(result.as_str().unwrap()).await?;

    Ok(())
}

fn main() {

    let cmd_def = CliCommandMap::new()
        .insert(
            "backup",
            CliCommand::new(&API_METHOD_BACKUP)
                .arg_param(&["store", "pool"])
                .completion_cb("store", complete_datastore_name)
                .completion_cb("pool", complete_pool_name)
        )
        .insert(
            "barcode-label",
            CliCommand::new(&API_METHOD_BARCODE_LABEL_MEDIA)
                .completion_cb("drive", complete_drive_name)
                .completion_cb("pool", complete_pool_name)
        )
        .insert(
            "rewind",
            CliCommand::new(&API_METHOD_REWIND)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "scan",
            CliCommand::new(&API_METHOD_DEBUG_SCAN)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "status",
            CliCommand::new(&API_METHOD_STATUS)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "eod",
            CliCommand::new(&API_METHOD_MOVE_TO_EOM)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "erase",
            CliCommand::new(&API_METHOD_ERASE_MEDIA)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "eject",
            CliCommand::new(&API_METHOD_EJECT_MEDIA)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "inventory",
            CliCommand::new(&API_METHOD_INVENTORY)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "read-label",
            CliCommand::new(&API_METHOD_READ_LABEL)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "cartridge-memory",
            CliCommand::new(&API_METHOD_CARTRIDGE_MEMORY)
                .completion_cb("drive", complete_drive_name)
        )
        .insert(
            "label",
            CliCommand::new(&API_METHOD_LABEL_MEDIA)
                .completion_cb("drive", complete_drive_name)
                .completion_cb("pool", complete_pool_name)

        )
        .insert("changer", changer_commands())
        .insert("drive", drive_commands())
        .insert("pool", pool_commands())
        .insert("media", media_commands())
        .insert(
            "load-media",
            CliCommand::new(&API_METHOD_LOAD_MEDIA)
                .arg_param(&["changer-id"])
                .completion_cb("drive", complete_drive_name)
                .completion_cb("changer-id", complete_media_changer_id)
        )
        ;

    let mut rpcenv = CliEnvironment::new();
    rpcenv.set_auth_id(Some(String::from("root@pam")));

    proxmox_backup::tools::runtime::main(run_async_cli_command(cmd_def, rpcenv));
}