package git

/*
#include <git2.h>

extern int _go_git_visit_submodule(git_repository *repo, void *fct);
*/
import "C"

import (
	"errors"
	"runtime"
	"unsafe"
)

// SubmoduleUpdateOptions
type SubmoduleUpdateOptions struct {
	*CheckoutOpts
	*FetchOptions
}

// Submodule
type Submodule struct {
	ptr *C.git_submodule
	r   *Repository
}

func newSubmoduleFromC(ptr *C.git_submodule, r *Repository) *Submodule {
	s := &Submodule{ptr: ptr, r: r}
	runtime.SetFinalizer(s, (*Submodule).Free)
	return s
}

func (sub *Submodule) Free() {
	runtime.SetFinalizer(sub, nil)
	C.git_submodule_free(sub.ptr)
}

type SubmoduleUpdate int

const (
	SubmoduleUpdateCheckout SubmoduleUpdate = C.GIT_SUBMODULE_UPDATE_CHECKOUT
	SubmoduleUpdateRebase   SubmoduleUpdate = C.GIT_SUBMODULE_UPDATE_REBASE
	SubmoduleUpdateMerge    SubmoduleUpdate = C.GIT_SUBMODULE_UPDATE_MERGE
	SubmoduleUpdateNone     SubmoduleUpdate = C.GIT_SUBMODULE_UPDATE_NONE
)

type SubmoduleIgnore int

const (
	SubmoduleIgnoreNone      SubmoduleIgnore = C.GIT_SUBMODULE_IGNORE_NONE
	SubmoduleIgnoreUntracked SubmoduleIgnore = C.GIT_SUBMODULE_IGNORE_UNTRACKED
	SubmoduleIgnoreDirty     SubmoduleIgnore = C.GIT_SUBMODULE_IGNORE_DIRTY
	SubmoduleIgnoreAll       SubmoduleIgnore = C.GIT_SUBMODULE_IGNORE_ALL
)

type SubmoduleStatus int

const (
	SubmoduleStatusInHead          SubmoduleStatus = C.GIT_SUBMODULE_STATUS_IN_HEAD
	SubmoduleStatusInIndex         SubmoduleStatus = C.GIT_SUBMODULE_STATUS_IN_INDEX
	SubmoduleStatusInConfig        SubmoduleStatus = C.GIT_SUBMODULE_STATUS_IN_CONFIG
	SubmoduleStatusInWd            SubmoduleStatus = C.GIT_SUBMODULE_STATUS_IN_WD
	SubmoduleStatusIndexAdded      SubmoduleStatus = C.GIT_SUBMODULE_STATUS_INDEX_ADDED
	SubmoduleStatusIndexDeleted    SubmoduleStatus = C.GIT_SUBMODULE_STATUS_INDEX_DELETED
	SubmoduleStatusIndexModified   SubmoduleStatus = C.GIT_SUBMODULE_STATUS_INDEX_MODIFIED
	SubmoduleStatusWdUninitialized SubmoduleStatus = C.GIT_SUBMODULE_STATUS_WD_UNINITIALIZED
	SubmoduleStatusWdAdded         SubmoduleStatus = C.GIT_SUBMODULE_STATUS_WD_ADDED
	SubmoduleStatusWdDeleted       SubmoduleStatus = C.GIT_SUBMODULE_STATUS_WD_DELETED
	SubmoduleStatusWdModified      SubmoduleStatus = C.GIT_SUBMODULE_STATUS_WD_MODIFIED
	SubmoduleStatusWdIndexModified SubmoduleStatus = C.GIT_SUBMODULE_STATUS_WD_INDEX_MODIFIED
	SubmoduleStatusWdWdModified    SubmoduleStatus = C.GIT_SUBMODULE_STATUS_WD_WD_MODIFIED
	SubmoduleStatusWdUntracked     SubmoduleStatus = C.GIT_SUBMODULE_STATUS_WD_UNTRACKED
)

type SubmoduleRecurse int

const (
	SubmoduleRecurseNo       SubmoduleRecurse = C.GIT_SUBMODULE_RECURSE_NO
	SubmoduleRecurseYes      SubmoduleRecurse = C.GIT_SUBMODULE_RECURSE_YES
	SubmoduleRecurseOndemand SubmoduleRecurse = C.GIT_SUBMODULE_RECURSE_ONDEMAND
)

type SubmoduleCollection struct {
	repo *Repository
}

func SubmoduleStatusIsUnmodified(status int) bool {
	o := SubmoduleStatus(status) & ^(SubmoduleStatusInHead | SubmoduleStatusInIndex |
		SubmoduleStatusInConfig | SubmoduleStatusInWd)
	return o == 0
}

func (c *SubmoduleCollection) Lookup(name string) (*Submodule, error) {
	cname := C.CString(name)
	defer C.free(unsafe.Pointer(cname))

	var ptr *C.git_submodule

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_lookup(&ptr, c.repo.ptr, cname)
	if ret < 0 {
		return nil, MakeGitError(ret)
	}

	return newSubmoduleFromC(ptr, c.repo), nil
}

// SubmoduleCallback is a function that is called for every submodule found in SubmoduleCollection.Foreach.
type SubmoduleCallback func(sub *Submodule, name string) int
type submoduleCallbackData struct {
	callback    SubmoduleCallback
	errorTarget *error
}

//export submoduleCallback
func submoduleCallback(csub unsafe.Pointer, name *C.char, handle unsafe.Pointer) C.int {
	sub := &Submodule{(*C.git_submodule)(csub), nil}

	data, ok := pointerHandles.Get(handle).(submoduleCallbackData)
	if !ok {
		panic("invalid submodule visitor callback")
	}

	ret := data.callback(sub, C.GoString(name))
	if ret < 0 {
		*data.errorTarget = errors.New(ErrorCode(ret).String())
		return C.int(ErrorCodeUser)
	}

	return C.int(ErrorCodeOK)
}

func (c *SubmoduleCollection) Foreach(callback SubmoduleCallback) error {
	var err error
	data := submoduleCallbackData{
		callback:    callback,
		errorTarget: &err,
	}
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	handle := pointerHandles.Track(data)
	defer pointerHandles.Untrack(handle)

	ret := C._go_git_visit_submodule(c.repo.ptr, handle)
	runtime.KeepAlive(c)
	if ret == C.int(ErrorCodeUser) && err != nil {
		return err
	}
	if ret < 0 {
		return MakeGitError(ret)
	}

	return nil
}

func (c *SubmoduleCollection) Add(url, path string, use_git_link bool) (*Submodule, error) {
	curl := C.CString(url)
	defer C.free(unsafe.Pointer(curl))
	cpath := C.CString(path)
	defer C.free(unsafe.Pointer(cpath))

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	var ptr *C.git_submodule
	ret := C.git_submodule_add_setup(&ptr, c.repo.ptr, curl, cpath, cbool(use_git_link))
	if ret < 0 {
		return nil, MakeGitError(ret)
	}
	return newSubmoduleFromC(ptr, c.repo), nil
}

func (sub *Submodule) FinalizeAdd() error {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_add_finalize(sub.ptr)
	runtime.KeepAlive(sub)
	if ret < 0 {
		return MakeGitError(ret)
	}
	return nil
}

func (sub *Submodule) AddToIndex(write_index bool) error {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_add_to_index(sub.ptr, cbool(write_index))
	runtime.KeepAlive(sub)
	if ret < 0 {
		return MakeGitError(ret)
	}
	return nil
}

func (sub *Submodule) Name() string {
	n := C.GoString(C.git_submodule_name(sub.ptr))
	runtime.KeepAlive(sub)
	return n
}

func (sub *Submodule) Path() string {
	n := C.GoString(C.git_submodule_path(sub.ptr))
	runtime.KeepAlive(sub)
	return n
}

func (sub *Submodule) Url() string {
	n := C.GoString(C.git_submodule_url(sub.ptr))
	runtime.KeepAlive(sub)
	return n
}

func (c *SubmoduleCollection) SetUrl(submodule, url string) error {
	csubmodule := C.CString(submodule)
	defer C.free(unsafe.Pointer(csubmodule))
	curl := C.CString(url)
	defer C.free(unsafe.Pointer(curl))

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_set_url(c.repo.ptr, csubmodule, curl)
	runtime.KeepAlive(c)
	if ret < 0 {
		return MakeGitError(ret)
	}
	return nil
}

func (sub *Submodule) IndexId() *Oid {
	var id *Oid
	idx := C.git_submodule_index_id(sub.ptr)
	if idx != nil {
		id = newOidFromC(idx)
	}
	runtime.KeepAlive(sub)
	return id
}

func (sub *Submodule) HeadId() *Oid {
	var id *Oid
	idx := C.git_submodule_head_id(sub.ptr)
	if idx != nil {
		id = newOidFromC(idx)
	}
	runtime.KeepAlive(sub)
	return id
}

func (sub *Submodule) WdId() *Oid {
	var id *Oid
	idx := C.git_submodule_wd_id(sub.ptr)
	if idx != nil {
		id = newOidFromC(idx)
	}
	runtime.KeepAlive(sub)
	return id
}

func (sub *Submodule) Ignore() SubmoduleIgnore {
	o := C.git_submodule_ignore(sub.ptr)
	runtime.KeepAlive(sub)
	return SubmoduleIgnore(o)
}

func (c *SubmoduleCollection) SetIgnore(submodule string, ignore SubmoduleIgnore) error {
	csubmodule := C.CString(submodule)
	defer C.free(unsafe.Pointer(csubmodule))

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_set_ignore(c.repo.ptr, csubmodule, C.git_submodule_ignore_t(ignore))
	runtime.KeepAlive(c)
	if ret < 0 {
		return MakeGitError(ret)
	}

	return nil
}

func (sub *Submodule) UpdateStrategy() SubmoduleUpdate {
	o := C.git_submodule_update_strategy(sub.ptr)
	runtime.KeepAlive(sub)
	return SubmoduleUpdate(o)
}

func (c *SubmoduleCollection) SetUpdate(submodule string, update SubmoduleUpdate) error {
	csubmodule := C.CString(submodule)
	defer C.free(unsafe.Pointer(csubmodule))

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_set_update(c.repo.ptr, csubmodule, C.git_submodule_update_t(update))
	runtime.KeepAlive(c)
	if ret < 0 {
		return MakeGitError(ret)
	}

	return nil
}

func (sub *Submodule) FetchRecurseSubmodules() SubmoduleRecurse {
	return SubmoduleRecurse(C.git_submodule_fetch_recurse_submodules(sub.ptr))
}

func (c *SubmoduleCollection) SetFetchRecurseSubmodules(submodule string, recurse SubmoduleRecurse) error {
	csubmodule := C.CString(submodule)
	defer C.free(unsafe.Pointer(csubmodule))

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_set_fetch_recurse_submodules(c.repo.ptr, csubmodule, C.git_submodule_recurse_t(recurse))
	runtime.KeepAlive(c)
	if ret < 0 {
		return MakeGitError(C.int(ret))
	}
	return nil
}

func (sub *Submodule) Init(overwrite bool) error {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_init(sub.ptr, cbool(overwrite))
	runtime.KeepAlive(sub)
	if ret < 0 {
		return MakeGitError(ret)
	}
	return nil
}

func (sub *Submodule) Sync() error {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_sync(sub.ptr)
	runtime.KeepAlive(sub)
	if ret < 0 {
		return MakeGitError(ret)
	}
	return nil
}

func (sub *Submodule) Open() (*Repository, error) {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	var ptr *C.git_repository
	ret := C.git_submodule_open(&ptr, sub.ptr)
	runtime.KeepAlive(sub)
	if ret < 0 {
		return nil, MakeGitError(ret)
	}
	return newRepositoryFromC(ptr), nil
}

func (sub *Submodule) Update(init bool, opts *SubmoduleUpdateOptions) error {
	var err error
	cOpts := populateSubmoduleUpdateOptions(&C.git_submodule_update_options{}, opts, &err)
	defer freeSubmoduleUpdateOptions(cOpts)

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_submodule_update(sub.ptr, cbool(init), cOpts)
	runtime.KeepAlive(sub)
	if ret == C.int(ErrorCodeUser) && err != nil {
		return err
	}
	if ret < 0 {
		return MakeGitError(ret)
	}

	return nil
}

func populateSubmoduleUpdateOptions(ptr *C.git_submodule_update_options, opts *SubmoduleUpdateOptions, errorTarget *error) *C.git_submodule_update_options {
	C.git_submodule_update_options_init(ptr, C.GIT_SUBMODULE_UPDATE_OPTIONS_VERSION)

	if opts == nil {
		return nil
	}

	populateCheckoutOptions(&ptr.checkout_opts, opts.CheckoutOpts, errorTarget)
	populateFetchOptions(&ptr.fetch_opts, opts.FetchOptions)

	return ptr
}

func freeSubmoduleUpdateOptions(ptr *C.git_submodule_update_options) {
	if ptr == nil {
		return
	}
	freeCheckoutOptions(&ptr.checkout_opts)
}