-- Leave empty for public repos, or add "your-token-here"
local GIT_TOKEN = ""
-- Update config
local GIT_URL = "https://git.ejebring.com/eejebring/CC-tweaked-Gitea-Client/raw/branch/main/git.lua"
local GIT_FILE = "git.lua"

-- Parse a Gitea URL like: https://gitea.example.com/owner/repo or /owner/repo/branch/filename
-- local function parseGiteaURL(url)
--     local protocol, domain, path = url:match("^(https?://([^/]+))(/[^?]*)")
--     if not protocol then
--         protocol, domain, path = "https://gitea.local", "gitea.local", url
--     end

--     -- Remove trailing slashes and clean path
--     path = path:gsub("/+$", "")

--     -- Extract components from path (format: /owner/repo or /owner/repo/branch)
--     local parts = {}
--     for segment in path:gmatch("[^/]+") do
--         if segment ~= "" then table.insert(parts, segment) end
--     end

--     if #parts < 2 then
--         return nil, "Invalid URL format. Expected: https://domain.com/owner/repo"
--     end

--     local owner = parts[1]
--     local repo = parts[2]
--     local branch = parts[3] or "master"

--     return {
--         base = protocol .. "/" .. domain,
--         owner = owner,
--         repo = repo,
--         branch = branch
--     }
-- end

---@param str string
---@param comp string
function string.beginsWith(str, comp)
    local compLen = string.len(comp)
    local begining = string.sub(str, 0, compLen)
    return begining == comp
end

---@param str string
---@param comp string
function string.endsWith(str, comp)
    local reverseStr = string.reverse(str)
    local reverseComp = string.reverse(comp)
    return string.beginsWith(reverseStr, reverseComp)
end

---@param str string
---@param delimiter string
function string.split(str, delimiter)
    local returnTable = {}
    for k in string.gmatch(str, "([^" .. delimiter .. "]+)")
    do
        returnTable[#returnTable + 1] = k
    end
    return returnTable
end

local protocols = { "http://", "https://" }
local ending = ".git"
---@param url string
local function parseGiteaURL(url)
    local info = {
        protocol = "",
        origin = "",
        owner = "",
        repo = "",
        treeUrl = "",
    }
    local lowerUrl = string.lower(url)
    if not string.endsWith(lowerUrl, ending) then error("A gitea link needs to end with " .. ending) end
    for _, proto in pairs(protocols) do
        if string.beginsWith(lowerUrl, proto) then
            info.protocol = proto
            break
        end
    end
    local urlLen = string.len(url)
    local protoLen = string.len(info.protocol)
    local endLen = string.len(ending)
    local cleaned = string.sub(url, protoLen + 1, urlLen - endLen)

    local urlParts = string.split(cleaned, "/")
    if not (#urlParts) == 3 then error("Unexpected link length.") end
    info.origin, info.owner, info.repo = urlParts[0], urlParts[1], urlParts[2]

    info.treeUrl =
        ("%s%s/api/v1/repos/%s/%s/git/trees/%s%s?recursive=1")
        :format(info.protocol, info.origin, info.owner, info.repo, ending)
    print()
    print("protocol: ", info.protocol)
    print("origin: ", info.origin)
    print("owner: ", info.owner)
    print("repo: ", info.repo)
    print("treeUrl: ", info.treeUrl)
    for k, v in pairs(info) do
        if v == "" or v == nil then
            error("Could not parse " .. k .. " from link.")
        end
    end
    print("treeUrl: ", info.treeUrl)
    return info
end

local function downloadFile(base, owner, repo, branch, path, target)
    local url = ("%s/api/v1/repos/%s/%s/raw/%s/%s"):format(base, owner, repo, branch, path)

    local req = { url = url }
    if GIT_TOKEN ~= "" then
        req.headers = { Authorization = "token " .. GIT_TOKEN }
    end

    local response = http.get(req)
    if not response then error("Failed to download: " .. path) end

    local data = response.readAll()
    response.close()

    local file, fileError = fs.open(target, "w")
    if file then
        file.write(data)
        file.close()
    else
        error("Could not download file '" .. target "' due to: " .. fileError)
    end
end

local function cloneRepo(url)
    local info = parseGiteaURL(url)
    -- if not info then error(err) end

    print("Cloning: " .. info.owner .. "/" .. info.repo .. "@" .. info.branch)

    -- local treeUrl = ("%s/api/v1/repos/%s/%s/git/trees/%s?recursive=1"):format(info.base, info.owner, info.repo,info.branch)

    local req = { url = info.treeUrl }
    if GIT_TOKEN ~= "" then
        req.headers = { Authorization = "token " .. GIT_TOKEN }
    end

    local resp = http.get(req)
    if not resp then error("Cannot access repository. Check URL or token.") end
    local responseJSON = resp.readAll()
    resp.close()
    if not responseJSON then error("Response returned empty.") end

    local tree = textutils.unserializeJSON(responseJSON)
    if not tree then error("Response could not be unserialized") end

    local count = 0
    for _, node in ipairs(tree.tree) do
        if node.type == "blob" then
            local localPath = ("git/%s/%s/%s"):format(info.owner, info.repo, node.path)
            local dir = fs.getDir(localPath)

            if not fs.isDir(dir) then fs.makeDir(dir) end

            downloadFile(info.base, info.owner, info.repo, info.branch, node.path, localPath)
            count = count + 1
        end
    end

    print(("Cloned %d files to /home/git/%s/%s"):format(count, info.owner, info.repo))
end

local args = { ... }
if args[1] == "clone" and args[2] then
    cloneRepo(args[2])
elseif args[1] == "update" then
    local resp = http.get(GIT_URL)
    if not resp then error("Failed to download update.") end
    local code = resp.readAll()
    if not code then error("Recived empty response from server.") end
    local file = fs.open(GIT_FILE, "w+")
    if not file then error("Could not overwite " .. GIT_FILE) end
    file.write(code)
else
    print("Usage:")
    print("  git update")
    print("  git clone <full-gitea-url>")
    print("")
    print("Examples:")
    print('  git clone "https://gitea.example.com/user/myrepo"')
    --print('  git clone "https://gitea.example.com/user/myrepo/tree/main/path/to/file.lua"')
    print("")
    print("Set GIT_TOKEN variable above for private repos.")
end