// Copyright 2021 syzkaller project authors. All rights reserved.
// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.

package main

import (
	"encoding/json"
)

// publicApiBugDescription is used to serve the /bug HTTP requests
// and provide JSON description of the BUG. Backward compatible.
type publicAPIBugDescription struct {
	Version     int         `json:"version"`
	Title       string      `json:"title,omitempty"`
	ID          string      `json:"id"`
	FixCommits  []vcsCommit `json:"fix-commits,omitempty"`
	CauseCommit *vcsCommit  `json:"cause-commit,omitempty"`
	// links to the discussions
	Discussions []string                    `json:"discussions,omitempty"`
	Crashes     []publicAPICrashDescription `json:"crashes,omitempty"`
}

type vcsCommit struct {
	Title  string `json:"title"`
	Link   string `json:"link,omitempty"`
	Hash   string `json:"hash,omitempty"`
	Repo   string `json:"repo,omitempty"`
	Branch string `json:"branch,omitempty"`
}

type publicAPICrashDescription struct {
	Title               string `json:"title"`
	SyzReproducer       string `json:"syz-reproducer,omitempty"`
	CReproducer         string `json:"c-reproducer,omitempty"`
	KernelConfig        string `json:"kernel-config,omitempty"`
	KernelSourceGit     string `json:"kernel-source-git,omitempty"`
	KernelSourceCommit  string `json:"kernel-source-commit,omitempty"`
	SyzkallerGit        string `json:"syzkaller-git,omitempty"`
	SyzkallerCommit     string `json:"syzkaller-commit,omitempty"`
	CompilerDescription string `json:"compiler-description,omitempty"`
	Architecture        string `json:"architecture,omitempty"`
	CrashReport         string `json:"crash-report-link,omitempty"`
}

func getExtAPIDescrForBugPage(bugPage *uiBugPage) *publicAPIBugDescription {
	return &publicAPIBugDescription{
		Version: 1,
		Title:   bugPage.Bug.Title,
		ID:      bugPage.Bug.ID,
		Discussions: func() []string {
			if bugPage.Bug.ExternalLink == "" {
				return nil
			}
			return []string{bugPage.Bug.ExternalLink}
		}(),
		FixCommits: getBugFixCommits(bugPage.Bug),
		CauseCommit: func() *vcsCommit {
			if bugPage.BisectCause == nil || bugPage.BisectCause.Commit == nil {
				return nil
			}
			bisectCause := bugPage.BisectCause
			return &vcsCommit{
				Title:  bisectCause.Commit.Title,
				Link:   bisectCause.Commit.Link,
				Hash:   bisectCause.Commit.Hash,
				Repo:   bisectCause.KernelRepo,
				Branch: bisectCause.KernelBranch}
		}(),
		Crashes: func() []publicAPICrashDescription {
			var res []publicAPICrashDescription
			for _, crash := range bugPage.Crashes.Crashes {
				res = append(res, publicAPICrashDescription{
					Title:              crash.Title,
					SyzReproducer:      crash.ReproSyzLink,
					CReproducer:        crash.ReproCLink,
					KernelConfig:       crash.KernelConfigLink,
					KernelSourceGit:    crash.KernelCommitLink,
					KernelSourceCommit: crash.KernelCommit,
					SyzkallerGit:       crash.SyzkallerCommitLink,
					SyzkallerCommit:    crash.SyzkallerCommit,
					// TODO: add the CompilerDescription
					// TODO: add the Architecture
					CrashReport: crash.ReportLink,
				})
			}
			return res
		}(),
	}
}

func getBugFixCommits(bug *uiBug) []vcsCommit {
	var res []vcsCommit
	for _, commit := range bug.Commits {
		res = append(res, vcsCommit{
			Title:  commit.Title,
			Link:   commit.Link,
			Hash:   commit.Hash,
			Repo:   commit.Repo,
			Branch: commit.Branch,
		})
	}
	return res
}

type publicAPIBugGroup struct {
	Version int `json:"version"`
	Bugs    []publicAPIBug
}

type publicAPIBug struct {
	Title       string      `json:"title,omitempty"`
	Link        string      `json:"link"`
	LastUpdated string      `json:"last-updated,omitempty"`
	FixCommits  []vcsCommit `json:"fix-commits,omitempty"`
}

func getExtAPIDescrForBugGroups(bugGroups []*uiBugGroup) *publicAPIBugGroup {
	return &publicAPIBugGroup{
		Version: 1,
		Bugs: func() []publicAPIBug {
			var res []publicAPIBug
			for _, group := range bugGroups {
				for _, bug := range group.Bugs {
					res = append(res, publicAPIBug{
						Title:      bug.Title,
						Link:       bug.Link,
						FixCommits: getBugFixCommits(bug),
					})
				}
			}
			return res
		}(),
	}
}

func GetJSONDescrFor(page interface{}) ([]byte, error) {
	var res interface{}
	switch i := page.(type) {
	case *uiBugPage:
		res = getExtAPIDescrForBugPage(i)
	case *uiTerminalPage:
		res = getExtAPIDescrForBugGroups([]*uiBugGroup{i.Bugs})
	case *uiMainPage:
		res = getExtAPIDescrForBugGroups(i.Groups)
	default:
		return nil, ErrClientNotFound
	}
	return json.MarshalIndent(res, "", "\t")
}