package obioptions

import (
	"fmt"
	"os"
	"runtime"
	"sync"

	"git.metabarcoding.org/obitools/obitools4/obitools4/pkg/obidefault"
	"git.metabarcoding.org/obitools/obitools4/obitools4/pkg/obiformats"
	"git.metabarcoding.org/obitools/obitools4/obitools4/pkg/obiutils"
	log "github.com/sirupsen/logrus"

	"github.com/DavidGamba/go-getoptions"

	"net/http"
	_ "net/http/pprof"
)

var _Debug = false
var _Pprof = false
var _PprofMudex = 10
var _PprofGoroutine = 6060
var __seq_as_taxa__ = false

var __defaut_taxonomy_mutex__ sync.Mutex

type ArgumentParser func([]string) (*getoptions.GetOpt, []string)

// RegisterGlobalOptions registers the global options shared by all obitools
// commands onto the given GetOpt instance. It does NOT register --help,
// which must be handled by the caller (either as a Bool option or via
// HelpCommand for subcommand-based parsers).
func RegisterGlobalOptions(options *getoptions.GetOpt) {
	options.Bool("version", false,
		options.Description("Prints the version and exits."))

	options.BoolVar(&_Debug, "debug", false,
		options.GetEnv("OBIDEBUG"),
		options.Description("Enable debug mode, by setting log level to debug."))

	options.BoolVar(&_Pprof, "pprof", false,
		options.Description("Enable pprof server. Look at the log for details."))

	options.IntVar(obidefault.MaxCPUPtr(), "max-cpu", obidefault.MaxCPU(),
		options.GetEnv("OBIMAXCPU"),
		options.Description("Number of parallele threads computing the result"))

	options.IntVar(&_PprofMudex, "pprof-mutex", _PprofMudex,
		options.GetEnv("OBIPPROFMUTEX"),
		options.Description("Enable profiling of mutex lock."))

	options.IntVar(&_PprofGoroutine, "pprof-goroutine", _PprofGoroutine,
		options.GetEnv("OBIPPROFGOROUTINE"),
		options.Description("Enable profiling of goroutine blocking profile."))

	options.IntVar(obidefault.BatchSizePtr(), "batch-size", obidefault.BatchSize(),
		options.GetEnv("OBIBATCHSIZE"),
		options.Description("Number of sequence per batch for paralelle processing"))

	options.StringVar(obidefault.BatchMemStrPtr(), "batch-mem", "",
		options.GetEnv("OBIBATCHMEM"),
		options.Description("Maximum memory per batch (e.g. 128K, 64M, 1G). Overrides --batch-size when set."))

	options.Bool("solexa", false,
		options.GetEnv("OBISOLEXA"),
		options.Description("Decodes quality string according to the Solexa specification."))

	options.BoolVar(obidefault.SilentWarningPtr(), "silent-warning", obidefault.SilentWarning(),
		options.GetEnv("OBIWARNING"),
		options.Description("Stop printing of the warning message"),
	)
}

// ProcessParsedOptions handles the post-parse logic common to all obitools
// commands: help, version, debug, pprof, taxonomy, cpu configuration, etc.
// It receives the GetOpt instance and the parse error (if any).
func ProcessParsedOptions(options *getoptions.GetOpt, parseErr error) {
	// Note: "help" may not be registered as a Bool (e.g. when using HelpCommand
	// for subcommand-based parsers). Only check if it won't panic.
	// We use a recover guard to be safe.
	func() {
		defer func() { recover() }()
		if options.Called("help") {
			fmt.Fprint(os.Stderr, options.Help())
			os.Exit(0)
		}
	}()

	if options.Called("version") {
		fmt.Fprintf(os.Stderr, "OBITools %s\n", VersionString())
		os.Exit(0)
	}

	if options.Called("taxonomy") {
		__defaut_taxonomy_mutex__.Lock()
		defer __defaut_taxonomy_mutex__.Unlock()
		taxonomy, err := obiformats.LoadTaxonomy(
			obidefault.SelectedTaxonomy(),
			!obidefault.AreAlternativeNamesSelected(),
			SeqAsTaxa(),
		)

		if err != nil {
			log.Fatalf("Cannot load default taxonomy: %v", err)
		}

		taxonomy.SetAsDefault()
	}

	log.SetLevel(log.InfoLevel)
	if options.Called("debug") {
		log.SetLevel(log.DebugLevel)
		log.Debugln("Switch to debug level logging")
	}

	if options.Called("pprof") {
		url := "localhost:6060"
		go http.ListenAndServe(url, nil)
		log.Infof("Start a pprof server at address %s/debug/pprof", url)
		log.Info("Profil can be followed running concurrently the command :")
		log.Info("  go tool pprof -http=127.0.0.1:8080 'http://localhost:6060/debug/pprof/profile?seconds=30'")
	}

	if options.Called("pprof-mutex") {
		url := "localhost:6060"
		go http.ListenAndServe(url, nil)
		runtime.SetMutexProfileFraction(_PprofMudex)
		log.Infof("Start a pprof server at address %s/debug/pprof", url)
		log.Info("Profil can be followed running concurrently the command :")
		log.Info("  go tool pprof -http=127.0.0.1:8080 'http://localhost:6060/debug/pprof/mutex'")
	}

	if options.Called("pprof-goroutine") {
		url := "localhost:6060"
		go http.ListenAndServe(url, nil)
		runtime.SetBlockProfileRate(_PprofGoroutine)
		log.Infof("Start a pprof server at address %s/debug/pprof", url)
		log.Info("Profil can be followed running concurrently the command :")
		log.Info("  go tool pprof -http=127.0.0.1:8080 'http://localhost:6060/debug/pprof/block'")
	}

	// Handle user errors
	if parseErr != nil {
		fmt.Fprintf(os.Stderr, "ERROR: %s\n\n", parseErr)
		fmt.Fprint(os.Stderr, options.Help(getoptions.HelpSynopsis))
		os.Exit(1)
	}

	runtime.GOMAXPROCS(obidefault.MaxCPU())

	if options.Called("max-cpu") {
		log.Printf("CPU number limited to %d", obidefault.MaxCPU())
	}

	if options.Called("no-singleton") {
		log.Printf("No singleton option set")
	}

	log.Printf("Number of workers set %d", obidefault.ParallelWorkers())

	if options.Called("solexa") {
		obidefault.SetReadQualitiesShift(64)
	}

	if options.Called("batch-mem") {
		n, err := obiutils.ParseMemSize(obidefault.BatchMemStr())
		if err != nil {
			log.Fatalf("Invalid --batch-mem value %q: %v", obidefault.BatchMemStr(), err)
		}
		obidefault.SetBatchMem(n)
		log.Printf("Memory-based batching enabled: %s per batch", obidefault.BatchMemStr())
	}
}

func GenerateOptionParser(program string,
	documentation string,
	optionset ...func(*getoptions.GetOpt)) ArgumentParser {

	options := getoptions.New()
	options.Self(program, documentation)
	options.SetMode(getoptions.Bundling)
	options.SetUnknownMode(getoptions.Fail)
	options.Bool("help", false, options.Alias("h", "?"))

	RegisterGlobalOptions(options)

	for _, o := range optionset {
		o(options)
	}

	return func(args []string) (*getoptions.GetOpt, []string) {
		remaining, err := options.Parse(args[1:])
		ProcessParsedOptions(options, err)
		return options, remaining
	}
}

func LoadTaxonomyOptionSet(options *getoptions.GetOpt, required, alternatiive bool) {
	if required {
		options.StringVar(obidefault.SelectedTaxonomyPtr(), "taxonomy", obidefault.SelectedTaxonomy(),
			options.Alias("t"),
			options.Required(),
			options.Description("Path to the taxonomy database."))
	} else {
		options.StringVar(obidefault.SelectedTaxonomyPtr(), "taxonomy", obidefault.SelectedTaxonomy(),
			options.Alias("t"),
			options.Description("Path to the taxonomy database."))
	}
	if alternatiive {
		options.BoolVar(obidefault.AlternativeNamesSelectedPtr(), "alternative-names", obidefault.AreAlternativeNamesSelected(),
			options.Alias("a"),
			options.Description("Enable the search on all alternative names and not only scientific names."))
	}

	options.BoolVar(obidefault.FailOnTaxonomyPtr(), "fail-on-taxonomy",
		obidefault.FailOnTaxonomy(),
		options.Description("Make obitools failing on error if a used taxid is not a currently valid one"),
	)

	options.BoolVar(obidefault.UpdateTaxidPtr(), "update-taxid", obidefault.UpdateTaxid(),
		options.Description("Make obitools automatically updating the taxid that are declared merged to a newest one."),
	)

	options.BoolVar(obidefault.UseRawTaxidsPtr(), "raw-taxid", obidefault.UseRawTaxids(),
		options.Description("When set, taxids are printed in files with any supplementary information (taxon name and rank)"),
	)
	options.BoolVar(&__seq_as_taxa__, "with-leaves", __seq_as_taxa__,
		options.Description("If taxonomy is extracted from a sequence file, sequences are added as leave of their taxid annotation"),
	)
}

// CLIIsDebugMode returns whether the CLI is in debug mode.
//
// The debug mode is activated by the command line option --debug or
// the environment variable OBIDEBUG.
// It can be activated programmatically by the SetDebugOn() function.
//
// No parameters.
// Returns a boolean indicating if the CLI is in debug mode.
func CLIIsDebugMode() bool {
	return _Debug
}

func SeqAsTaxa() bool {
	return __seq_as_taxa__
}

// SetDebugOn sets the debug mode on.
func SetDebugOn() {
	_Debug = true
}

// SetDebugOff sets the debug mode off.
func SetDebugOff() {
	_Debug = false
}