// Copyright 2018 The Gogs Authors. All rights reserved.
// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package gitea

import (
	"fmt"
	"net/url"
	"regexp"
	"time"
)

// Identity for a person's identity like an author or committer
type Identity struct {
	Name  string `json:"name"`
	Email string `json:"email"`
}

// CommitMeta contains meta information of a commit in terms of API.
type CommitMeta struct {
	URL string `json:"url"`
	SHA string `json:"sha"`
}

// CommitUser contains information of a user in the context of a commit.
type CommitUser struct {
	Identity
	Date string `json:"date"`
}

// RepoCommit contains information of a commit in the context of a repository.
type RepoCommit struct {
	URL       string      `json:"url"`
	Author    *CommitUser `json:"author"`
	Committer *CommitUser `json:"committer"`
	Message   string      `json:"message"`
	Tree      *CommitMeta `json:"tree"`
}

// Commit contains information generated from a Git commit.
type Commit struct {
	*CommitMeta
	HTMLURL    string        `json:"html_url"`
	RepoCommit *RepoCommit   `json:"commit"`
	Author     *User         `json:"author"`
	Committer  *User         `json:"committer"`
	Parents    []*CommitMeta `json:"parents"`
}

// CommitDateOptions store dates for GIT_AUTHOR_DATE and GIT_COMMITTER_DATE
type CommitDateOptions struct {
	Author    time.Time `json:"author"`
	Committer time.Time `json:"committer"`
}

// SHAPattern can be used to determine if a string is an valid sha
var SHAPattern = regexp.MustCompile(`^[0-9a-f]{4,40}$`)

// GetSingleCommit returns a single commit
func (c *Client) GetSingleCommit(user, repo, commitID string) (*Commit, error) {
	commit := new(Commit)
	if e := c.CheckServerVersionConstraint("<1.12.0"); e == nil || SHAPattern.MatchString(commitID) {
		return commit, c.getParsedResponse("GET", fmt.Sprintf("/repos/%s/%s/git/commits/%s", user, repo, commitID), nil, nil, &commit)
	}
	return commit, c.getParsedResponse("GET", fmt.Sprintf("/repos/%s/%s/commits/%s", user, repo, commitID), nil, nil, &commit)
}

// ListCommitOptions list commit options
type ListCommitOptions struct {
	ListOptions
	//SHA or branch to start listing commits from (usually 'master')
	SHA string
}

// QueryEncode turns options into querystring argument
func (opt *ListCommitOptions) QueryEncode() string {
	query := opt.ListOptions.getURLQuery()
	if opt.SHA != "" {
		query.Add("sha", opt.SHA)
	}
	return query.Encode()
}

// ListRepoCommits return list of commits from a repo
func (c *Client) ListRepoCommits(user, repo string, opt ListCommitOptions) ([]*Commit, error) {
	link, _ := url.Parse(fmt.Sprintf("/repos/%s/%s/commits", user, repo))
	opt.setDefaults()
	commits := make([]*Commit, 0, opt.PageSize)
	link.RawQuery = opt.QueryEncode()
	return commits, c.getParsedResponse("GET", link.String(), nil, nil, &commits)
}