local forge = require('forge')

---@class forge.GitHub: forge.Forge
local M = {
  name = 'github',
  cli = 'gh',
  kinds = { issue = 'issue', pr = 'pr' },
  labels = {
    issue = 'Issues',
    pr = 'PRs',
    pr_one = 'PR',
    pr_full = 'Pull Requests',
    ci = 'CI/CD',
  },
}

local function nwo()
  local url = forge.remote_web_url()
  return url:match('github%.com/(.+)$') or ''
end

---@param kind string
---@param state string
---@param state string
---@return string[]
function M:list_pr_json_cmd(state)
  return {
    'gh',
    'pr',
    'list',
    '--limit',
    tostring(forge.config().display.limits.pulls),
    '--state',
    state,
    '--json',
    'number,title,headRefName,state,author,createdAt',
  }
end

---@param state string
---@return string[]
function M:list_issue_json_cmd(state)
  return {
    'gh',
    'issue',
    'list',
    '--limit',
    tostring(forge.config().display.limits.issues),
    '--state',
    state,
    '--json',
    'number,title,state,author,createdAt',
  }
end

function M:pr_json_fields()
  return {
    number = 'number',
    title = 'title',
    branch = 'headRefName',
    state = 'state',
    author = 'author',
    created_at = 'createdAt',
  }
end

function M:issue_json_fields()
  return {
    number = 'number',
    title = 'title',
    state = 'state',
    author = 'author',
    created_at = 'createdAt',
  }
end

---@param kind string
---@param num string
function M:view_web(kind, num)
  vim.system({ 'gh', kind, 'view', num, '--web' })
end

---@param loc string
---@param branch string
function M:browse(loc, branch)
  vim.system({ 'gh', 'browse', loc, '--branch', branch })
end

function M:browse_root()
  vim.system({ 'gh', 'browse' })
end

function M:browse_branch(branch)
  vim.system({ 'gh', 'browse', '--branch', branch })
end

function M:browse_commit(sha)
  vim.system({ 'gh', 'browse', sha })
end

function M:checkout_cmd(num)
  return { 'gh', 'pr', 'checkout', num }
end

---@param loc string
function M:yank_branch(loc)
  forge.yank_url({ 'gh', 'browse', loc, '-n' })
end

---@param loc string
function M:yank_commit(loc)
  forge.yank_url({ 'gh', 'browse', loc, '--commit=last', '-n' })
end

---@param num string
---@return string[]
function M:fetch_pr(num)
  return { 'git', 'fetch', 'origin', ('pull/%s/head:pr-%s'):format(num, num) }
end

---@param num string
---@return string[]
function M:pr_base_cmd(num)
  return {
    'gh',
    'pr',
    'view',
    num,
    '--json',
    'baseRefName',
    '--jq',
    '.baseRefName',
  }
end

---@param branch string
---@return string[]
function M:pr_for_branch_cmd(branch)
  return {
    'gh',
    'pr',
    'list',
    '--head',
    branch,
    '--json',
    'number',
    '--jq',
    '.[0].number',
  }
end

---@param num string
---@return string
function M:checks_cmd(num)
  return ('gh pr checks %s'):format(num)
end

---@param num string
---@return string[]
function M:checks_json_cmd(num)
  return {
    'gh',
    'pr',
    'checks',
    num,
    '--json',
    'name,bucket,link,state,startedAt,completedAt',
  }
end

---@param run_id string
---@param failed_only boolean
---@return string[]
function M:check_log_cmd(run_id, failed_only)
  local lines = forge.config().ci.lines
  local flag = failed_only and '--log-failed' or '--log'
  return {
    'sh',
    '-c',
    ('gh run view %s -R %s %s | tail -n %d'):format(run_id, nwo(), flag, lines),
  }
end

---@param run_id string
---@return string[]
function M:check_tail_cmd(run_id)
  return { 'gh', 'run', 'watch', run_id, '-R', nwo() }
end

function M:list_runs_json_cmd(branch)
  local cmd = {
    'gh',
    'run',
    'list',
    '--json',
    'databaseId,name,headBranch,status,conclusion,event,url,createdAt',
    '--limit',
    tostring(forge.config().display.limits.runs),
  }
  if branch then
    table.insert(cmd, '--branch')
    table.insert(cmd, branch)
  end
  return cmd
end

function M:normalize_run(entry)
  local status = entry.status or ''
  if status == 'completed' then
    status = entry.conclusion or 'unknown'
  end
  return {
    id = tostring(entry.databaseId or ''),
    name = entry.name or '',
    branch = entry.headBranch or '',
    status = status,
    event = entry.event or '',
    url = entry.url or '',
    created_at = entry.createdAt or '',
  }
end

function M:run_log_cmd(id, failed_only)
  local lines = forge.config().ci.lines
  local flag = failed_only and '--log-failed' or '--log'
  return {
    'sh',
    '-c',
    ('gh run view %s -R %s %s | tail -n %d'):format(id, nwo(), flag, lines),
  }
end

function M:run_tail_cmd(id)
  return { 'gh', 'run', 'watch', id, '-R', nwo() }
end

---@param num string
---@param method string
---@return string[]
function M:merge_cmd(num, method)
  return { 'gh', 'pr', 'merge', num, '--' .. method }
end

---@param num string
---@return string[]
function M:approve_cmd(num)
  return { 'gh', 'pr', 'review', num, '--approve' }
end

---@param num string
---@return string[]
function M:close_cmd(num)
  return { 'gh', 'pr', 'close', num }
end

---@param num string
---@return string[]
function M:reopen_cmd(num)
  return { 'gh', 'pr', 'reopen', num }
end

---@param num string
---@return string[]
function M:close_issue_cmd(num)
  return { 'gh', 'issue', 'close', num }
end

---@param num string
---@return string[]
function M:reopen_issue_cmd(num)
  return { 'gh', 'issue', 'reopen', num }
end

---@param title string
---@param body string
---@param base string
---@param draft boolean
---@param reviewers string[]?
---@return string[]
function M:create_pr_cmd(title, body, base, draft, reviewers)
  local cmd = { 'gh', 'pr', 'create', '--title', title, '--body', body, '--base', base }
  if draft then
    table.insert(cmd, '--draft')
  end
  for _, r in ipairs(reviewers or {}) do
    table.insert(cmd, '--reviewer')
    table.insert(cmd, r)
  end
  return cmd
end

---@return string[]
function M:create_pr_web_cmd()
  return { 'gh', 'pr', 'create', '--web' }
end

---@return string[]
function M:default_branch_cmd()
  return { 'gh', 'repo', 'view', '--json', 'defaultBranchRef', '--jq', '.defaultBranchRef.name' }
end

---@return string[]
function M:template_paths()
  return {
    '.github/pull_request_template.md',
    '.github/PULL_REQUEST_TEMPLATE.md',
    '.github/PULL_REQUEST_TEMPLATE/',
  }
end

---@param num string
---@param is_draft boolean
---@return string[]?
function M:draft_toggle_cmd(num, is_draft)
  if is_draft then
    return { 'gh', 'pr', 'ready', num }
  end
  return { 'gh', 'pr', 'ready', num, '--undo' }
end

---@return forge.RepoInfo
function M:repo_info()
  local result = vim
    .system({
      'gh',
      'repo',
      'view',
      nwo(),
      '--json',
      'viewerPermission,squashMergeAllowed,rebaseMergeAllowed,mergeCommitAllowed',
    }, { text = true })
    :wait()

  local ok, data = pcall(vim.json.decode, result.stdout or '{}')
  if not ok or type(data) ~= 'table' then
    data = {}
  end
  local methods = {}
  if data.squashMergeAllowed then
    table.insert(methods, 'squash')
  end
  if data.rebaseMergeAllowed then
    table.insert(methods, 'rebase')
  end
  if data.mergeCommitAllowed then
    table.insert(methods, 'merge')
  end

  return {
    permission = (data.viewerPermission or 'READ'):upper(),
    merge_methods = methods,
  }
end

---@param num string
---@return forge.PRState
function M:pr_state(num)
  local result = vim
    .system({
      'gh',
      'pr',
      'view',
      num,
      '--json',
      'state,mergeable,reviewDecision,isDraft',
    }, { text = true })
    :wait()

  local ok, data = pcall(vim.json.decode, result.stdout or '{}')
  if not ok or type(data) ~= 'table' then
    data = {}
  end
  return {
    state = data.state or 'UNKNOWN',
    mergeable = data.mergeable or 'UNKNOWN',
    review_decision = data.reviewDecision or '',
    is_draft = data.isDraft == true,
  }
end

return M