// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"net/http"
)

func errorPage404(w http.ResponseWriter, params map[string]any) {
	w.WriteHeader(http.StatusNotFound)
	_ = templates.ExecuteTemplate(w, "404", params)
}

func errorPage400(w http.ResponseWriter, params map[string]any, msg string) {
	w.WriteHeader(http.StatusBadRequest)
	params["complete_error_msg"] = msg
	_ = templates.ExecuteTemplate(w, "400", params)
}

func errorPage400Colon(w http.ResponseWriter, params map[string]any) {
	w.WriteHeader(http.StatusBadRequest)
	_ = templates.ExecuteTemplate(w, "400_colon", params)
}

func errorPage403(w http.ResponseWriter, params map[string]any, msg string) {
	w.WriteHeader(http.StatusForbidden)
	params["complete_error_msg"] = msg
	_ = templates.ExecuteTemplate(w, "403", params)
}

func errorPage451(w http.ResponseWriter, params map[string]any, msg string) {
	w.WriteHeader(http.StatusUnavailableForLegalReasons)
	params["complete_error_msg"] = msg
	_ = templates.ExecuteTemplate(w, "451", params)
}

func errorPage500(w http.ResponseWriter, params map[string]any, msg string) {
	w.WriteHeader(http.StatusInternalServerError)
	params["complete_error_msg"] = msg
	_ = templates.ExecuteTemplate(w, "500", params)
}

func errorPage501(w http.ResponseWriter, params map[string]any) {
	w.WriteHeader(http.StatusNotImplemented)
	_ = templates.ExecuteTemplate(w, "501", params)
}

// SPDX-License-Identifier: AGPL-3.0-only

// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"errors"
	"net/http"
	"path/filepath"
	"strconv"

	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgtype"
	"go.lindenii.runxiyu.org/forge/internal/misc"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// httpHandleGroupIndex provides index pages for groups, which includes a list
// of its subgroups and repos, as well as a form for group maintainers to
// create repos.
func (s *Server) httpHandleGroupIndex(writer http.ResponseWriter, request *http.Request, params map[string]any) {
	var groupPath []string
	var repos []nameDesc
	var subgroups []nameDesc
	var err error
	var groupID int
	var groupDesc string

	groupPath = params["group_path"].([]string)

	// The group itself
	err = s.database.QueryRow(request.Context(), `
		WITH RECURSIVE group_path_cte AS (
			SELECT
				id,
				parent_group,
				name,
				1 AS depth
			FROM groups
			WHERE name = ($1::text[])[1]
				AND parent_group IS NULL

			UNION ALL

			SELECT
				g.id,
				g.parent_group,
				g.name,
				group_path_cte.depth + 1
			FROM groups g
			JOIN group_path_cte ON g.parent_group = group_path_cte.id
			WHERE g.name = ($1::text[])[group_path_cte.depth + 1]
				AND group_path_cte.depth + 1 <= cardinality($1::text[])
		)
		SELECT c.id, COALESCE(g.description, '')
		FROM group_path_cte c
		JOIN groups g ON g.id = c.id
		WHERE c.depth = cardinality($1::text[])
	`,
		pgtype.FlatArray[string](groupPath),
	).Scan(&groupID, &groupDesc)

	if errors.Is(err, pgx.ErrNoRows) {

		errorPage404(writer, params)

		web.ErrorPage404(templates, writer, params)

		return
	} else if err != nil {

		errorPage500(writer, params, "Error getting group: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting group: "+err.Error())

		return
	}

	// ACL
	var count int
	err = s.database.QueryRow(request.Context(), `
		SELECT COUNT(*)
		FROM user_group_roles
		WHERE user_id = $1
			AND group_id = $2
	`, params["user_id"].(int), groupID).Scan(&count)
	if err != nil {

		errorPage500(writer, params, "Error checking access: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error checking access: "+err.Error())

		return
	}
	directAccess := (count > 0)

	if request.Method == http.MethodPost {
		if !directAccess {

			errorPage403(writer, params, "You do not have direct access to this group")

			web.ErrorPage403(templates, writer, params, "You do not have direct access to this group")

			return
		}

		repoName := request.FormValue("repo_name")
		repoDesc := request.FormValue("repo_desc")
		contribReq := request.FormValue("repo_contrib")
		if repoName == "" {

			errorPage400(writer, params, "Repo name is required")

			web.ErrorPage400(templates, writer, params, "Repo name is required")

			return
		}

		var newRepoID int
		err := s.database.QueryRow(
			request.Context(),
			`INSERT INTO repos (name, description, group_id, contrib_requirements)
	 VALUES ($1, $2, $3, $4)
	 RETURNING id`,
			repoName,
			repoDesc,
			groupID,
			contribReq,
		).Scan(&newRepoID)
		if err != nil {

			errorPage500(writer, params, "Error creating repo: "+err.Error())

			web.ErrorPage500(templates, writer, params, "Error creating repo: "+err.Error())

			return
		}

		filePath := filepath.Join(s.config.Git.RepoDir, strconv.Itoa(newRepoID)+".git")

		_, err = s.database.Exec(
			request.Context(),
			`UPDATE repos
	 SET filesystem_path = $1
	 WHERE id = $2`,
			filePath,
			newRepoID,
		)
		if err != nil {

			errorPage500(writer, params, "Error updating repo path: "+err.Error())

			web.ErrorPage500(templates, writer, params, "Error updating repo path: "+err.Error())

			return
		}

		if err = s.gitInit(filePath); err != nil {

			errorPage500(writer, params, "Error initializing repo: "+err.Error())

			web.ErrorPage500(templates, writer, params, "Error initializing repo: "+err.Error())

			return
		}

		misc.RedirectUnconditionally(writer, request)
		return
	}

	// Repos
	var rows pgx.Rows
	rows, err = s.database.Query(request.Context(), `
		SELECT name, COALESCE(description, '')
		FROM repos
		WHERE group_id = $1
	`, groupID)
	if err != nil {

		errorPage500(writer, params, "Error getting repos: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting repos: "+err.Error())

		return
	}
	defer rows.Close()

	for rows.Next() {
		var name, description string
		if err = rows.Scan(&name, &description); err != nil {

			errorPage500(writer, params, "Error getting repos: "+err.Error())

			web.ErrorPage500(templates, writer, params, "Error getting repos: "+err.Error())

			return
		}
		repos = append(repos, nameDesc{name, description})
	}
	if err = rows.Err(); err != nil {

		errorPage500(writer, params, "Error getting repos: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting repos: "+err.Error())

		return
	}

	// Subgroups
	rows, err = s.database.Query(request.Context(), `
		SELECT name, COALESCE(description, '')
		FROM groups
		WHERE parent_group = $1
	`, groupID)
	if err != nil {

		errorPage500(writer, params, "Error getting subgroups: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting subgroups: "+err.Error())

		return
	}
	defer rows.Close()

	for rows.Next() {
		var name, description string
		if err = rows.Scan(&name, &description); err != nil {

			errorPage500(writer, params, "Error getting subgroups: "+err.Error())

			web.ErrorPage500(templates, writer, params, "Error getting subgroups: "+err.Error())

			return
		}
		subgroups = append(subgroups, nameDesc{name, description})
	}
	if err = rows.Err(); err != nil {

		errorPage500(writer, params, "Error getting subgroups: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting subgroups: "+err.Error())

		return
	}

	params["repos"] = repos
	params["subgroups"] = subgroups
	params["description"] = groupDesc
	params["direct_access"] = directAccess

	renderTemplate(writer, "group", params)
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"net/http"
	"runtime"

	"github.com/dustin/go-humanize"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// httpHandleIndex provides the main index page which includes a list of groups
// and some global information such as SSH keys.
func (s *Server) httpHandleIndex(writer http.ResponseWriter, request *http.Request, params map[string]any) {
	var err error
	var groups []nameDesc

	groups, err = s.queryNameDesc(request.Context(), "SELECT name, COALESCE(description, '') FROM groups WHERE parent_group IS NULL")
	if err != nil {

		errorPage500(writer, params, "Error querying groups: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error querying groups: "+err.Error())

		return
	}
	params["groups"] = groups

	// Memory currently allocated
	memstats := runtime.MemStats{} //exhaustruct:ignore
	runtime.ReadMemStats(&memstats)
	params["mem"] = humanize.IBytes(memstats.Alloc)
	renderTemplate(writer, "index", params)
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"crypto/rand"
	"encoding/base64"
	"errors"
	"fmt"
	"net/http"
	"time"

	"github.com/alexedwards/argon2id"
	"github.com/jackc/pgx/v5"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// httpHandleLogin provides the login page for local users.
func (s *Server) httpHandleLogin(writer http.ResponseWriter, request *http.Request, params map[string]any) {
	var username, password string
	var userID int
	var passwordHash string
	var err error
	var passwordMatches bool
	var cookieValue string
	var now time.Time
	var expiry time.Time
	var cookie http.Cookie

	if request.Method != http.MethodPost {
		renderTemplate(writer, "login", params)
		return
	}

	username = request.PostFormValue("username")
	password = request.PostFormValue("password")

	err = s.database.QueryRow(request.Context(),
		"SELECT id, COALESCE(password, '') FROM users WHERE username = $1",
		username,
	).Scan(&userID, &passwordHash)
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			params["login_error"] = "Unknown username"
			renderTemplate(writer, "login", params)
			return
		}

		errorPage500(writer, params, "Error querying user information: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error querying user information: "+err.Error())

		return
	}
	if passwordHash == "" {
		params["login_error"] = "User has no password"
		renderTemplate(writer, "login", params)
		return
	}

	if passwordMatches, err = argon2id.ComparePasswordAndHash(password, passwordHash); err != nil {

		errorPage500(writer, params, "Error comparing password and hash: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error comparing password and hash: "+err.Error())

		return
	}

	if !passwordMatches {
		params["login_error"] = "Invalid password"
		renderTemplate(writer, "login", params)
		return
	}

	if cookieValue, err = randomUrlsafeStr(16); err != nil {

		errorPage500(writer, params, "Error getting random string: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting random string: "+err.Error())

		return
	}

	now = time.Now()
	expiry = now.Add(time.Duration(s.config.HTTP.CookieExpiry) * time.Second)

	cookie = http.Cookie{
		Name:     "session",
		Value:    cookieValue,
		SameSite: http.SameSiteLaxMode,
		HttpOnly: true,
		Secure:   false, // TODO
		Expires:  expiry,
		Path:     "/",
	} //exhaustruct:ignore

	http.SetCookie(writer, &cookie)

	_, err = s.database.Exec(request.Context(), "INSERT INTO sessions (user_id, session_id) VALUES ($1, $2)", userID, cookieValue)
	if err != nil {

		errorPage500(writer, params, "Error inserting session: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error inserting session: "+err.Error())

		return
	}

	http.Redirect(writer, request, "/", http.StatusSeeOther)
}

// randomUrlsafeStr generates a random string of the given entropic size
// using the URL-safe base64 encoding. The actual size of the string returned
// will be 4*sz.
func randomUrlsafeStr(sz int) (string, error) {
	r := make([]byte, 3*sz)
	_, err := rand.Read(r)
	if err != nil {
		return "", fmt.Errorf("error generating random string: %w", err)
	}
	return base64.RawURLEncoding.EncodeToString(r), nil
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"fmt"
	"net/http"
	"strings"

	"github.com/go-git/go-git/v5"
	"github.com/go-git/go-git/v5/plumbing"
	"github.com/go-git/go-git/v5/plumbing/filemode"
	"github.com/go-git/go-git/v5/plumbing/format/diff"
	"github.com/go-git/go-git/v5/plumbing/object"
	"go.lindenii.runxiyu.org/forge/internal/misc"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// usableFilePatch is a [diff.FilePatch] that is structured in a way more
// friendly for use in HTML templates.
type usableFilePatch struct {
	From   diff.File
	To     diff.File
	Chunks []usableChunk
}

// usableChunk is a [diff.Chunk] that is structured in a way more friendly for
// use in HTML templates.
type usableChunk struct {
	Operation diff.Operation
	Content   string
}

func httpHandleRepoCommit(writer http.ResponseWriter, request *http.Request, params map[string]any) {
	var repo *git.Repository
	var commitIDStrSpec, commitIDStrSpecNoSuffix string
	var commitID plumbing.Hash
	var parentCommitHash plumbing.Hash
	var commitObj *object.Commit
	var commitIDStr string
	var err error
	var patch *object.Patch

	repo, commitIDStrSpec = params["repo"].(*git.Repository), params["commit_id"].(string)

	commitIDStrSpecNoSuffix = strings.TrimSuffix(commitIDStrSpec, ".patch")
	commitID = plumbing.NewHash(commitIDStrSpecNoSuffix)
	if commitObj, err = repo.CommitObject(commitID); err != nil {

		errorPage500(writer, params, "Error getting commit object: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting commit object: "+err.Error())

		return
	}
	if commitIDStrSpecNoSuffix != commitIDStrSpec {
		var patchStr string
		if patchStr, err = fmtCommitPatch(commitObj); err != nil {

			errorPage500(writer, params, "Error formatting patch: "+err.Error())

			web.ErrorPage500(templates, writer, params, "Error formatting patch: "+err.Error())

			return
		}
		fmt.Fprintln(writer, patchStr)
		return
	}
	commitIDStr = commitObj.Hash.String()

	if commitIDStr != commitIDStrSpec {
		http.Redirect(writer, request, commitIDStr, http.StatusSeeOther)
		return
	}

	params["commit_object"] = commitObj
	params["commit_id"] = commitIDStr

	parentCommitHash, patch, err = commitToPatch(commitObj)
	if err != nil {

		errorPage500(writer, params, "Error getting patch from commit: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting patch from commit: "+err.Error())

		return
	}
	params["parent_commit_hash"] = parentCommitHash.String()
	params["patch"] = patch

	params["file_patches"] = makeUsableFilePatches(patch)

	renderTemplate(writer, "repo_commit", params)
}

type fakeDiffFile struct {
	hash plumbing.Hash
	mode filemode.FileMode
	path string
}

func (f fakeDiffFile) Hash() plumbing.Hash {
	return f.hash
}

func (f fakeDiffFile) Mode() filemode.FileMode {
	return f.mode
}

func (f fakeDiffFile) Path() string {
	return f.path
}

var nullFakeDiffFile = fakeDiffFile{ //nolint:gochecknoglobals
	hash: plumbing.NewHash("0000000000000000000000000000000000000000"),
	mode: misc.FirstOrPanic(filemode.New("100644")),
	path: "",
}

func makeUsableFilePatches(patch diff.Patch) (usableFilePatches []usableFilePatch) {
	// TODO: Remove unnecessary context
	// TODO: Prepend "+"/"-"/" " instead of solely distinguishing based on color

	for _, filePatch := range patch.FilePatches() {
		var fromFile, toFile diff.File
		var ufp usableFilePatch
		chunks := []usableChunk{}

		fromFile, toFile = filePatch.Files()
		if fromFile == nil {
			fromFile = nullFakeDiffFile
		}
		if toFile == nil {
			toFile = nullFakeDiffFile
		}
		for _, chunk := range filePatch.Chunks() {
			var content string

			content = chunk.Content()
			if len(content) > 0 && content[0] == '\n' {
				content = "\n" + content
			} // Horrible hack to fix how browsers newlines that immediately proceed <pre>
			chunks = append(chunks, usableChunk{
				Operation: chunk.Type(),
				Content:   content,
			})
		}
		ufp = usableFilePatch{
			Chunks: chunks,
			From:   fromFile,
			To:     toFile,
		}
		usableFilePatches = append(usableFilePatches, ufp)
	}
	return
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"net/http"

	"github.com/jackc/pgx/v5"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// idTitleStatus describes properties of a merge request that needs to be
// present in MR listings.
type idTitleStatus struct {
	ID     int
	Title  string
	Status string
}

// httpHandleRepoContribIndex provides an index to merge requests of a repo.
func (s *Server) httpHandleRepoContribIndex(writer http.ResponseWriter, request *http.Request, params map[string]any) {
	var rows pgx.Rows
	var result []idTitleStatus
	var err error

	if rows, err = s.database.Query(request.Context(),
		"SELECT repo_local_id, COALESCE(title, 'Untitled'), status FROM merge_requests WHERE repo_id = $1",
		params["repo_id"],
	); err != nil {

		errorPage500(writer, params, "Error querying merge requests: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error querying merge requests: "+err.Error())

		return
	}
	defer rows.Close()

	for rows.Next() {
		var mrID int
		var mrTitle, mrStatus string
		if err = rows.Scan(&mrID, &mrTitle, &mrStatus); err != nil {

			errorPage500(writer, params, "Error scanning merge request: "+err.Error())

			web.ErrorPage500(templates, writer, params, "Error scanning merge request: "+err.Error())

			return
		}
		result = append(result, idTitleStatus{mrID, mrTitle, mrStatus})
	}
	if err = rows.Err(); err != nil {

		errorPage500(writer, params, "Error ranging over merge requests: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error ranging over merge requests: "+err.Error())

		return
	}
	params["merge_requests"] = result

	renderTemplate(writer, "repo_contrib_index", params)
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"net/http"
	"strconv"

	"github.com/go-git/go-git/v5"
	"github.com/go-git/go-git/v5/plumbing"
	"github.com/go-git/go-git/v5/plumbing/object"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// httpHandleRepoContribOne provides an interface to each merge request of a
// repo.
func (s *Server) httpHandleRepoContribOne(writer http.ResponseWriter, request *http.Request, params map[string]any) {
	var mrIDStr string
	var mrIDInt int
	var err error
	var title, status, srcRefStr, dstBranchStr string
	var repo *git.Repository
	var srcRefHash plumbing.Hash
	var dstBranchHash plumbing.Hash
	var srcCommit, dstCommit, mergeBaseCommit *object.Commit
	var mergeBases []*object.Commit

	mrIDStr = params["mr_id"].(string)
	mrIDInt64, err := strconv.ParseInt(mrIDStr, 10, strconv.IntSize)
	if err != nil {

		errorPage400(writer, params, "Merge request ID not an integer")

		web.ErrorPage400(templates, writer, params, "Merge request ID not an integer")

		return
	}
	mrIDInt = int(mrIDInt64)

	if err = s.database.QueryRow(request.Context(),
		"SELECT COALESCE(title, ''), status, source_ref, COALESCE(destination_branch, '') FROM merge_requests WHERE repo_id = $1 AND repo_local_id = $2",
		params["repo_id"], mrIDInt,
	).Scan(&title, &status, &srcRefStr, &dstBranchStr); err != nil {

		errorPage500(writer, params, "Error querying merge request: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error querying merge request: "+err.Error())

		return
	}

	repo = params["repo"].(*git.Repository)

	if srcRefHash, err = getRefHash(repo, "branch", srcRefStr); err != nil {

		errorPage500(writer, params, "Error getting source ref hash: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting source ref hash: "+err.Error())

		return
	}
	if srcCommit, err = repo.CommitObject(srcRefHash); err != nil {

		errorPage500(writer, params, "Error getting source commit: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting source commit: "+err.Error())

		return
	}
	params["source_commit"] = srcCommit

	if dstBranchStr == "" {
		dstBranchStr = "HEAD"
		dstBranchHash, err = getRefHash(repo, "", "")
	} else {
		dstBranchHash, err = getRefHash(repo, "branch", dstBranchStr)
	}
	if err != nil {

		errorPage500(writer, params, "Error getting destination branch hash: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting destination branch hash: "+err.Error())

		return
	}

	if dstCommit, err = repo.CommitObject(dstBranchHash); err != nil {

		errorPage500(writer, params, "Error getting destination commit: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting destination commit: "+err.Error())

		return
	}
	params["destination_commit"] = dstCommit

	if mergeBases, err = srcCommit.MergeBase(dstCommit); err != nil {

		errorPage500(writer, params, "Error getting merge base: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting merge base: "+err.Error())

		return
	}

	if len(mergeBases) < 1 {

		errorPage500(writer, params, "No merge base found for this merge request; these two branches do not share any common history")

		web.ErrorPage500(templates, writer, params, "No merge base found for this merge request; these two branches do not share any common history")

		// TODO
		return
	}

	mergeBaseCommit = mergeBases[0]
	params["merge_base"] = mergeBaseCommit

	patch, err := mergeBaseCommit.Patch(srcCommit)
	if err != nil {

		errorPage500(writer, params, "Error getting patch: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting patch: "+err.Error())

		return
	}
	params["file_patches"] = makeUsableFilePatches(patch)

	params["mr_title"], params["mr_status"], params["mr_source_ref"], params["mr_destination_branch"] = title, status, srcRefStr, dstBranchStr

	renderTemplate(writer, "repo_contrib_one", params)
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"net/http"

	"go.lindenii.runxiyu.org/forge/internal/git2c"
	"go.lindenii.runxiyu.org/forge/internal/render"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

type commitDisplay struct {
	Hash    string
	Author  string
	Email   string
	Date    string
	Message string
}

// httpHandleRepoIndex provides the front page of a repo using git2d.
func (s *Server) httpHandleRepoIndex(w http.ResponseWriter, req *http.Request, params map[string]any) {
	repoName := params["repo_name"].(string)
	groupPath := params["group_path"].([]string)

	_, repoPath, _, _, _, _, _ := s.getRepoInfo(req.Context(), groupPath, repoName, "") // TODO: Don't use getRepoInfo

	client, err := git2c.NewClient(s.config.Git.Socket)
	if err != nil {

		errorPage500(w, params, err.Error())

		web.ErrorPage500(templates, w, params, err.Error())

		return
	}
	defer client.Close()

	commits, readme, err := client.Cmd1(repoPath)
	if err != nil {

		errorPage500(w, params, err.Error())

		web.ErrorPage500(templates, w, params, err.Error())

		return
	}

	params["commits"] = commits
	params["readme_filename"] = readme.Filename
	_, params["readme"] = render.Readme(readme.Content, readme.Filename)

	renderTemplate(w, "repo_index", params)

	// TODO: Caching
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"net/http"

	"github.com/go-git/go-git/v5"
	"github.com/go-git/go-git/v5/plumbing"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// httpHandleRepoLog provides a page with a complete Git log.
//
// TODO: This currently provides all commits in the branch. It should be
// paginated and cached instead.
func httpHandleRepoLog(writer http.ResponseWriter, _ *http.Request, params map[string]any) {
	var repo *git.Repository
	var refHash plumbing.Hash
	var err error

	repo = params["repo"].(*git.Repository)

	if refHash, err = getRefHash(repo, params["ref_type"].(string), params["ref_name"].(string)); err != nil {

		errorPage500(writer, params, "Error getting ref hash: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting ref hash: "+err.Error())

		return
	}

	logOptions := git.LogOptions{From: refHash} //exhaustruct:ignore
	commitIter, err := repo.Log(&logOptions)
	if err != nil {

		errorPage500(writer, params, "Error getting recent commits: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting recent commits: "+err.Error())

		return
	}
	params["commits"], params["commits_err"] = commitIterSeqErr(commitIter)

	renderTemplate(writer, "repo_log", params)
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"fmt"
	"html/template"
	"net/http"
	"strings"

	"go.lindenii.runxiyu.org/forge/internal/git2c"
	"go.lindenii.runxiyu.org/forge/internal/misc"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// httpHandleRepoRaw serves raw files, or directory listings that point to raw
// files.
func (s *Server) httpHandleRepoRaw(writer http.ResponseWriter, request *http.Request, params map[string]any) {
	repoName := params["repo_name"].(string)
	groupPath := params["group_path"].([]string)
	rawPathSpec := params["rest"].(string)
	pathSpec := strings.TrimSuffix(rawPathSpec, "/")
	params["path_spec"] = pathSpec

	_, repoPath, _, _, _, _, _ := s.getRepoInfo(request.Context(), groupPath, repoName, "")

	client, err := git2c.NewClient(s.config.Git.Socket)
	if err != nil {

		errorPage500(writer, params, err.Error())

		web.ErrorPage500(templates, writer, params, err.Error())

		return
	}
	defer client.Close()

	files, content, err := client.Cmd2(repoPath, pathSpec)
	if err != nil {

		errorPage500(writer, params, err.Error())

		web.ErrorPage500(templates, writer, params, err.Error())

		return
	}

	switch {
	case files != nil:
		params["files"] = files
		params["readme_filename"] = "README.md"
		params["readme"] = template.HTML("<p>README rendering here is WIP again</p>") // TODO
		renderTemplate(writer, "repo_raw_dir", params)
	case content != "":
		if misc.RedirectNoDir(writer, request) {
			return
		}
		writer.Header().Set("Content-Type", "application/octet-stream")
		fmt.Fprint(writer, content)
	default:

		errorPage500(writer, params, "Unknown error fetching repo raw data")

		web.ErrorPage500(templates, writer, params, "Unknown error fetching repo raw data")

	}
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"html/template"
	"net/http"
	"strings"

	"go.lindenii.runxiyu.org/forge/internal/git2c"
	"go.lindenii.runxiyu.org/forge/internal/render"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// httpHandleRepoTree provides a friendly, syntax-highlighted view of
// individual files, and provides directory views that link to these files.
//
// TODO: Do not highlight files that are too large.
func (s *Server) httpHandleRepoTree(writer http.ResponseWriter, request *http.Request, params map[string]any) {
	repoName := params["repo_name"].(string)
	groupPath := params["group_path"].([]string)
	rawPathSpec := params["rest"].(string)
	pathSpec := strings.TrimSuffix(rawPathSpec, "/")
	params["path_spec"] = pathSpec

	_, repoPath, _, _, _, _, _ := s.getRepoInfo(request.Context(), groupPath, repoName, "")

	client, err := git2c.NewClient(s.config.Git.Socket)
	if err != nil {

		errorPage500(writer, params, err.Error())

		web.ErrorPage500(templates, writer, params, err.Error())

		return
	}
	defer client.Close()

	files, content, err := client.Cmd2(repoPath, pathSpec)
	if err != nil {

		errorPage500(writer, params, err.Error())

		web.ErrorPage500(templates, writer, params, err.Error())

		return
	}

	switch {
	case files != nil:
		params["files"] = files
		params["readme_filename"] = "README.md"
		params["readme"] = template.HTML("<p>README rendering here is WIP again</p>") // TODO
		renderTemplate(writer, "repo_tree_dir", params)
	case content != "":
		rendered := render.Highlight(pathSpec, content)
		params["file_contents"] = rendered
		renderTemplate(writer, "repo_tree_file", params)
	default:

		errorPage500(writer, params, "Unknown object type, something is seriously wrong")

		web.ErrorPage500(templates, writer, params, "Unknown object type, something is seriously wrong")

	}
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"net/http"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// httpHandleUsers is a useless stub.
func httpHandleUsers(writer http.ResponseWriter, _ *http.Request, params map[string]any) {

	errorPage501(writer, params)

	web.ErrorPage501(templates, writer, params)

}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package forge

import (
	"errors"
	"log/slog"
	"net/http"
	"net/url"
	"strconv"
	"strings"

	"github.com/jackc/pgx/v5"
	"go.lindenii.runxiyu.org/forge/internal/misc"

	"go.lindenii.runxiyu.org/forge/internal/web"

)

// ServeHTTP handles all incoming HTTP requests and routes them to the correct
// location.
//
// TODO: This function is way too large.
func (s *Server) ServeHTTP(writer http.ResponseWriter, request *http.Request) {
	var remoteAddr string
	if s.config.HTTP.ReverseProxy {
		remoteAddrs, ok := request.Header["X-Forwarded-For"]
		if ok && len(remoteAddrs) == 1 {
			remoteAddr = remoteAddrs[0]
		} else {
			remoteAddr = request.RemoteAddr
		}
	} else {
		remoteAddr = request.RemoteAddr
	}
	slog.Info("incoming http", "addr", remoteAddr, "method", request.Method, "uri", request.RequestURI)

	var segments []string
	var err error
	var sepIndex int
	params := make(map[string]any)

	if segments, _, err = misc.ParseReqURI(request.RequestURI); err != nil {

		errorPage400(writer, params, "Error parsing request URI: "+err.Error())

		web.ErrorPage400(templates, writer, params, "Error parsing request URI: "+err.Error())

		return
	}
	dirMode := false
	if segments[len(segments)-1] == "" {
		dirMode = true
		segments = segments[:len(segments)-1]
	}

	params["url_segments"] = segments
	params["dir_mode"] = dirMode
	params["global"] = s.globalData
	var userID int // 0 for none
	userID, params["username"], err = s.getUserFromRequest(request)
	params["user_id"] = userID
	if err != nil && !errors.Is(err, http.ErrNoCookie) && !errors.Is(err, pgx.ErrNoRows) {

		errorPage500(writer, params, "Error getting user info from request: "+err.Error())

		web.ErrorPage500(templates, writer, params, "Error getting user info from request: "+err.Error())

		return
	}

	if userID == 0 {
		params["user_id_string"] = ""
	} else {
		params["user_id_string"] = strconv.Itoa(userID)
	}

	for _, v := range segments {
		if strings.Contains(v, ":") {

			errorPage400Colon(writer, params)

			web.ErrorPage400Colon(templates, writer, params)

			return
		}
	}

	if len(segments) == 0 {
		s.httpHandleIndex(writer, request, params)
		return
	}

	if segments[0] == "-" {
		if len(segments) < 2 {

			errorPage404(writer, params)

			web.ErrorPage404(templates, writer, params)

			return
		} else if len(segments) == 2 && misc.RedirectDir(writer, request) {
			return
		}

		switch segments[1] {
		case "static":
			s.staticHandler.ServeHTTP(writer, request)
			return
		case "source":
			s.sourceHandler.ServeHTTP(writer, request)
			return
		}
	}

	if segments[0] == "-" {
		switch segments[1] {
		case "login":
			s.httpHandleLogin(writer, request, params)
			return
		case "users":
			httpHandleUsers(writer, request, params)
			return
		default:

			errorPage404(writer, params)

			web.ErrorPage404(templates, writer, params)

			return
		}
	}

	sepIndex = -1
	for i, part := range segments {
		if part == "-" {
			sepIndex = i
			break
		}
	}

	params["separator_index"] = sepIndex

	var groupPath []string
	var moduleType string
	var moduleName string

	if sepIndex > 0 {
		groupPath = segments[:sepIndex]
	} else {
		groupPath = segments
	}
	params["group_path"] = groupPath

	switch {
	case sepIndex == -1:
		if misc.RedirectDir(writer, request) {
			return
		}
		s.httpHandleGroupIndex(writer, request, params)
	case len(segments) == sepIndex+1:

		errorPage404(writer, params)

		web.ErrorPage404(templates, writer, params)

		return
	case len(segments) == sepIndex+2:

		errorPage404(writer, params)

		web.ErrorPage404(templates, writer, params)

		return
	default:
		moduleType = segments[sepIndex+1]
		moduleName = segments[sepIndex+2]
		switch moduleType {
		case "repos":
			params["repo_name"] = moduleName

			if len(segments) > sepIndex+3 {
				switch segments[sepIndex+3] {
				case "info":
					if err = s.httpHandleRepoInfo(writer, request, params); err != nil {

						errorPage500(writer, params, err.Error())

						web.ErrorPage500(templates, writer, params, err.Error())

					}
					return
				case "git-upload-pack":
					if err = s.httpHandleUploadPack(writer, request, params); err != nil {

						errorPage500(writer, params, err.Error())

						web.ErrorPage500(templates, writer, params, err.Error())

					}
					return
				}
			}

			if params["ref_type"], params["ref_name"], err = misc.GetParamRefTypeName(request); err != nil {
				if errors.Is(err, misc.ErrNoRefSpec) {
					params["ref_type"] = ""
				} else {

					errorPage400(writer, params, "Error querying ref type: "+err.Error())

					web.ErrorPage400(templates, writer, params, "Error querying ref type: "+err.Error())

					return
				}
			}

			if params["repo"], params["repo_description"], params["repo_id"], _, err = s.openRepo(request.Context(), groupPath, moduleName); err != nil {

				errorPage500(writer, params, "Error opening repo: "+err.Error())

				web.ErrorPage500(templates, writer, params, "Error opening repo: "+err.Error())

				return
			}

			repoURLRoot := "/"
			for _, part := range segments[:sepIndex+3] {
				repoURLRoot = repoURLRoot + url.PathEscape(part) + "/"
			}
			params["repo_url_root"] = repoURLRoot
			params["repo_patch_mailing_list"] = repoURLRoot[1:len(repoURLRoot)-1] + "@" + s.config.LMTP.Domain
			params["http_clone_url"] = s.genHTTPRemoteURL(groupPath, moduleName)
			params["ssh_clone_url"] = s.genSSHRemoteURL(groupPath, moduleName)

			if len(segments) == sepIndex+3 {
				if misc.RedirectDir(writer, request) {
					return
				}
				s.httpHandleRepoIndex(writer, request, params)
				return
			}

			repoFeature := segments[sepIndex+3]
			switch repoFeature {
			case "tree":
				if misc.AnyContain(segments[sepIndex+4:], "/") {

					errorPage400(writer, params, "Repo tree paths may not contain slashes in any segments")

					web.ErrorPage400(templates, writer, params, "Repo tree paths may not contain slashes in any segments")

					return
				}
				if dirMode {
					params["rest"] = strings.Join(segments[sepIndex+4:], "/") + "/"
				} else {
					params["rest"] = strings.Join(segments[sepIndex+4:], "/")
				}
				if len(segments) < sepIndex+5 && misc.RedirectDir(writer, request) {
					return
				}
				s.httpHandleRepoTree(writer, request, params)
			case "branches":
				if misc.RedirectDir(writer, request) {
					return
				}
				s.httpHandleRepoBranches(writer, request, params)
				return
			case "raw":
				if misc.AnyContain(segments[sepIndex+4:], "/") {

					errorPage400(writer, params, "Repo tree paths may not contain slashes in any segments")

					web.ErrorPage400(templates, writer, params, "Repo tree paths may not contain slashes in any segments")

					return
				}
				if dirMode {
					params["rest"] = strings.Join(segments[sepIndex+4:], "/") + "/"
				} else {
					params["rest"] = strings.Join(segments[sepIndex+4:], "/")
				}
				if len(segments) < sepIndex+5 && misc.RedirectDir(writer, request) {
					return
				}
				s.httpHandleRepoRaw(writer, request, params)
			case "log":
				if len(segments) > sepIndex+4 {

					errorPage400(writer, params, "Too many parameters")

					web.ErrorPage400(templates, writer, params, "Too many parameters")

					return
				}
				if misc.RedirectDir(writer, request) {
					return
				}
				httpHandleRepoLog(writer, request, params)
			case "commit":
				if len(segments) != sepIndex+5 {

					errorPage400(writer, params, "Incorrect number of parameters")

					web.ErrorPage400(templates, writer, params, "Incorrect number of parameters")

					return
				}
				if misc.RedirectNoDir(writer, request) {
					return
				}
				params["commit_id"] = segments[sepIndex+4]
				httpHandleRepoCommit(writer, request, params)
			case "contrib":
				if misc.RedirectDir(writer, request) {
					return
				}
				switch len(segments) {
				case sepIndex + 4:
					s.httpHandleRepoContribIndex(writer, request, params)
				case sepIndex + 5:
					params["mr_id"] = segments[sepIndex+4]
					s.httpHandleRepoContribOne(writer, request, params)
				default:

					errorPage400(writer, params, "Too many parameters")

					web.ErrorPage400(templates, writer, params, "Too many parameters")

				}
			default:

				errorPage404(writer, params)

				web.ErrorPage404(templates, writer, params)

				return
			}
		default:

			errorPage404(writer, params)

			web.ErrorPage404(templates, writer, params)

			return
		}
	}
}

// SPDX-License-Identifier: AGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>

package web

import (
	"html/template"
	"net/http"
)

func ErrorPage404(templates *template.Template, w http.ResponseWriter, params map[string]any) {
	w.WriteHeader(http.StatusNotFound)
	_ = templates.ExecuteTemplate(w, "404", params)
}

func ErrorPage400(templates *template.Template, w http.ResponseWriter, params map[string]any, msg string) {
	w.WriteHeader(http.StatusBadRequest)
	params["complete_error_msg"] = msg
	_ = templates.ExecuteTemplate(w, "400", params)
}

func ErrorPage400Colon(templates *template.Template, w http.ResponseWriter, params map[string]any) {
	w.WriteHeader(http.StatusBadRequest)
	_ = templates.ExecuteTemplate(w, "400_colon", params)
}

func ErrorPage403(templates *template.Template, w http.ResponseWriter, params map[string]any, msg string) {
	w.WriteHeader(http.StatusForbidden)
	params["complete_error_msg"] = msg
	_ = templates.ExecuteTemplate(w, "403", params)
}

func ErrorPage451(templates *template.Template, w http.ResponseWriter, params map[string]any, msg string) {
	w.WriteHeader(http.StatusUnavailableForLegalReasons)
	params["complete_error_msg"] = msg
	_ = templates.ExecuteTemplate(w, "451", params)
}

func ErrorPage500(templates *template.Template, w http.ResponseWriter, params map[string]any, msg string) {
	w.WriteHeader(http.StatusInternalServerError)
	params["complete_error_msg"] = msg
	_ = templates.ExecuteTemplate(w, "500", params)
}

func ErrorPage501(templates *template.Template, w http.ResponseWriter, params map[string]any) {
	w.WriteHeader(http.StatusNotImplemented)
	_ = templates.ExecuteTemplate(w, "501", params)
}