#!/bin/bash
# devdesk — persistent Claude Code sessions in tmux, shared by the browser UI and SSH.
#
#   devdesk attach [NAME]        attach to session NAME, creating it if needed; no NAME opens the picker
#   devdesk new NAME [PROJECT]   create session NAME (detached) in PROJECT's folder, or the default folder
#   devdesk rename OLD NEW       rename a session (running or dormant)
#   devdesk end NAME             stop session NAME and forget it
#   devdesk repo NAME            git + Gitea CI status of the session's folder (JSON)
#   devdesk alerts               firing/pending Grafana alerts (JSON)
#   devdesk ls                   list sessions
#   devdesk pick                 interactive picker
#
# The web UI calls `devdesk attach --list | --repo NAME | --alerts | --upload SESSION FILE BYTES |
# --new NAME [PROJECT] | --rename OLD NEW | --end NAME`
# through ttyd; those print JSON.
set -euo pipefail

# shellcheck source=libexec/devdesk-lib.sh
. "${DEVDESK_LIBEXEC:-/usr/lib/devdesk}/devdesk-lib.sh"

usage() {
    sed -n '2,12s/^# \{0,1\}//p' "$0"
}

# Tab-separated running sessions: name, dir, attached clients, last activity, windows.
running_tsv() {
    dd_server_up || return 0
    dd_tmux list-sessions -F '#{session_name}	#{session_path}	#{session_attached}	#{session_activity}	#{session_windows}' 2>/dev/null || true
}

# Tab-separated top-level project directories: slug, dir.
projects_tsv() {
    local d real root
    root=$(realpath -e -- "$DEVDESK_PROJECTS_ROOT" 2>/dev/null) || return 0
    for d in "$DEVDESK_PROJECTS_ROOT"/*/; do
        [ -d "$d" ] || continue
        d=${d%/}
        case ${d##*/} in node_modules | _* | lost+found) continue ;; esac
        # Only offer directories that attach would accept (no symlinks out of the root).
        real=$(realpath -e -- "$d" 2>/dev/null) || continue
        case "$real/" in "$root"/*) ;; *) continue ;; esac
        printf '%s\t%s\n' "$(dd_slugify "${d##*/}")" "$d"
    done
}

# {"<session>": {...}} merged from the per-session JSON files in DIR
# (status-line snapshots, hook states).
per_session_json() {
    local dir=$1 f
    if [ -d "$dir" ]; then
        for f in "$dir"/*.json; do
            [ -f "$f" ] || continue
            jq -cM --arg n "$(basename "$f" .json)" '{($n): .}' "$f" 2>/dev/null || true
        done
    fi | jq -cMs 'add // {}'
}

cmd_list() {
    local reg='{"sessions":{}}'
    [ -s "$DEVDESK_REGISTRY" ] && reg=$(cat "$DEVDESK_REGISTRY")
    jq -cMn \
        --argjson reg "$reg" \
        --arg run "$(running_tsv)" \
        --arg proj "$(projects_tsv)" \
        --argjson ctx "$(per_session_json "$DEVDESK_CONTEXT_DIR")" \
        --argjson st "$(per_session_json "$DEVDESK_STATUS_DIR")" \
        --arg dflt "$DEVDESK_DEFAULT_SESSION" \
        --arg root "$DEVDESK_PROJECTS_ROOT" '
        def rows($s): $s | split("\n") | map(select(length > 0) | split("\t"));
        ($reg.sessions // {}) as $known
        | [rows($run)[] | {name: .[0], dir: .[1], running: true,
                           attached: (.[2] | tonumber), activity: (.[3] | tonumber),
                           windows: (.[4] | tonumber)}] as $live
        | ($live | map(.name)) as $liveNames
        | {default: $dflt, root: $root,
           sessions: (
             ($live | map(. + {claude_session_id: ($known[.name].claude_session_id // null)}))
             + ($known | to_entries
                 | map(select(.key as $k | $liveNames | index($k) | not))
                 | map({name: .key, dir: .value.dir, running: false, attached: 0,
                        activity: null, windows: 0,
                        claude_session_id: (.value.claude_session_id // null)}))
           ) | map(. + {context: ($ctx[.name] // null), status: ($st[.name] // null)}),
           projects: ([{name: $dflt, dir: $root}]
                      + [rows($proj)[] | {name: .[0], dir: .[1]}
                         | select(.name | test("^[A-Za-z0-9][A-Za-z0-9_-]{0,63}$"))])}'
}

cmd_ls() {
    cmd_list | jq -Mr '
        .sessions | if length == 0 then "no sessions" else
        (["", "SESSION", "CLIENTS", "CONTEXT", "DIRECTORY"] | @tsv),
        (.[] | [(if .running then "●" else "○" end), .name, (.attached | tostring),
                (if .context.used_pct then "\(.context.used_pct | floor)%" else "-" end), .dir] | @tsv)
        end' | column -t -s $'\t'
}

session_exists() {
    { dd_server_up && dd_tmux has-session -t "=$1" 2>/dev/null; } || [ -n "$(dd_registry_get "$1" dir)" ]
}

create_detached() {
    local name=$1 dir=$2 args
    dd_tmux has-session -t "=$name" 2>/dev/null && return 0
    mapfile -d '' args < <(dd_new_session_args "$name" "$dir")
    # Another client may win the race; "duplicate session" is fine.
    dd_tmux new-session -d "${args[@]}" 2>/dev/null || dd_tmux has-session -t "=$name" 2>/dev/null ||
        dd_die "could not create session '$name'"
    dd_registry_set_dir "$name" "$dir"
}

cmd_new() {
    { [ $# -ge 1 ] && [ $# -le 2 ]; } || dd_die "usage: devdesk new NAME [PROJECT]"
    dd_valid_name "$1" || dd_die "invalid session name: $1"
    local dir
    if [ $# -eq 2 ]; then
        dd_valid_name "$2" || dd_die "invalid project name: $2"
        dir=$(dd_project_dir "$2") || dd_die "no project '$2' under $DEVDESK_PROJECTS_ROOT"
        ! session_exists "$1" || dd_die "a session named '$1' already exists"
    else
        dir=$(dd_resolve_dir "$1")
    fi
    dd_ensure_server
    create_detached "$1" "$dir"
}

cmd_rename() {
    [ $# -eq 2 ] || dd_die "usage: devdesk rename OLD NEW"
    local old=$1 new=$2 running=0
    dd_valid_name "$old" || dd_die "invalid session name: $old"
    dd_valid_name "$new" || dd_die "invalid session name: $new"
    [ "$old" != "$new" ] || return 0
    if dd_server_up && dd_tmux has-session -t "=$old" 2>/dev/null; then running=1; fi
    [ "$running" = 1 ] || [ -n "$(dd_registry_get "$old" dir)" ] || dd_die "no session named '$old'"
    ! session_exists "$new" || dd_die "a session named '$new' already exists"
    if [ "$running" = 1 ]; then
        dd_tmux rename-session -t "=$old" "$new"
        dd_tmux set-environment -t "=$new" DEVDESK_SESSION "$new"
    fi
    dd_registry_rename "$old" "$new"
}

cmd_end() {
    [ $# -eq 1 ] || dd_die "usage: devdesk end NAME"
    dd_valid_name "$1" || dd_die "invalid session name: $1"
    if dd_server_up; then
        dd_tmux kill-session -t "=$1" 2>/dev/null || true
    fi
    dd_registry_remove "$1"
}

# GET $DEVDESK_GITEA_URL/api/v1<path>; token optional (private repos only).
gitea_get() {
    local auth=()
    if [ -r "$DEVDESK_GITEA_TOKEN_FILE" ]; then
        auth=(-H "Authorization: token $(tr -d '[:space:]' <"$DEVDESK_GITEA_TOKEN_FILE")")
    fi
    curl -fsS --max-time 4 "${auth[@]}" "$DEVDESK_GITEA_URL/api/v1$1" 2>/dev/null
}

# owner/repo when REMOTE points at our Gitea (https or ssh, any configured host), else nothing.
gitea_slug() {
    local remote=$1 host hosts
    hosts="${DEVDESK_GITEA_URL#*://} $DEVDESK_GITEA_ALIASES"
    for host in $hosts; do
        host=${host%%/*}
        host=${host%%:*}
        if [[ $remote =~ [@/]${host//./\.}(:[0-9]+)?[:/]+([^/]+/[^/]+)$ ]]; then
            printf '%s\n' "${BASH_REMATCH[2]%.git}"
            return
        fi
    done
}

cmd_repo() {
    [ $# -eq 1 ] || dd_die "usage: devdesk repo NAME"
    dd_valid_name "$1" || dd_die "invalid session name: $1"
    local dir g branch sha="" dirty ahead=null behind=null upstream=false remote slug="" ci=null prs=null
    dir=$(dd_resolve_dir "$1")
    g=(git -c safe.directory='*' -C "$dir")
    if ! "${g[@]}" rev-parse --is-inside-work-tree >/dev/null 2>&1; then
        jq -cMn --arg s "$1" --arg dir "$dir" '{session: $s, dir: $dir, git: false}'
        return
    fi
    branch=$("${g[@]}" symbolic-ref --short -q HEAD || echo "(detached)")
    sha=$("${g[@]}" rev-parse -q --verify HEAD 2>/dev/null || true)
    dirty=$("${g[@]}" status --porcelain 2>/dev/null | wc -l)
    if "${g[@]}" rev-parse -q --verify '@{u}' >/dev/null 2>&1; then
        upstream=true
        read -r behind ahead < <("${g[@]}" rev-list --left-right --count '@{u}...HEAD')
    fi
    remote=$("${g[@]}" remote get-url origin 2>/dev/null || true)
    [ -n "$remote" ] && slug=$(gitea_slug "$remote")
    if [ -n "$slug" ] && [ -n "$sha" ]; then
        ci=$(gitea_get "/repos/$slug/commits/$sha/status" |
            jq -cM '{state, total: .total_count,
                     url: (.statuses[0]?.target_url | if . then sub("/jobs/[0-9]+$"; "") else null end),
                     jobs: [.statuses[]? | {name: .context, status}]}' 2>/dev/null) || ci=null
        prs=$(gitea_get "/repos/$slug/pulls?state=open&limit=50" | jq -M 'length' 2>/dev/null) || prs=null
    fi
    jq -cMn --arg s "$1" --arg dir "$dir" --arg branch "$branch" --arg sha "${sha:0:7}" \
        --argjson dirty "$dirty" --argjson ahead "$ahead" --argjson behind "$behind" \
        --argjson upstream "$upstream" --arg remote "$remote" --arg slug "$slug" \
        --arg web "$DEVDESK_GITEA_URL" --argjson ci "${ci:-null}" --argjson prs "${prs:-null}" '
        {session: $s, dir: $dir, git: true, branch: $branch, sha: $sha, dirty: $dirty,
         ahead: $ahead, behind: $behind, upstream: $upstream, remote: $remote,
         repo: (if $slug == "" then null else $slug end),
         url: (if $slug == "" then null else "\($web)/\($slug)" end),
         ci: (if $ci == null then null else $ci + {url: (if $ci.url then $web + $ci.url else null end)} end),
         prs: $prs}'
}

# Firing and pending Grafana alert rules, most severe first.
cmd_alerts() {
    if [ -z "$DEVDESK_GRAFANA_URL" ]; then
        jq -cMn '{configured: false, alerts: []}'
        return
    fi
    local auth=() raw
    if [ -r "$DEVDESK_GRAFANA_TOKEN_FILE" ]; then
        auth=(-H "Authorization: Bearer $(tr -d '[:space:]' <"$DEVDESK_GRAFANA_TOKEN_FILE")")
    fi
    if ! raw=$(curl -fsS --max-time 6 "${auth[@]}" "$DEVDESK_GRAFANA_URL/api/prometheus/grafana/api/v1/rules" 2>&1); then
        jq -cMn --arg e "${raw:-no response}" '{configured: true, error: $e, alerts: []}'
        return
    fi
    jq -cM --arg pub "$DEVDESK_GRAFANA_PUBLIC_URL" '
        def num: (tonumber? // .) | tostring;
        {configured: true, checked: (now | floor), alerts: [
            .data.groups[] | .name as $group | .file as $folder | .rules[]
            | select(.state == "firing" or .state == "pending")
            | . as $r
            | ([.alerts[]? | select(.state == "Alerting" or .state == "Pending")]) as $active
            | {name, state, severity: (.labels.severity // null), group: $group, folder: $folder,
               since: (.activeAt // $active[0].activeAt // null),
               summary: ((.annotations.summary // .annotations.description // "")
                         | gsub("\\{\\{ *\\$value *\\}\\}"; ($active[0].value // "?" | num))),
               instances: [$active[] | .labels
                            | del(.__alert_rule_uid__, .__grafana_origin__, .alertname, .grafana_folder, .__name__, .severity)
                            | to_entries | map("\(.key)=\(.value)") | join(" ")
                            | select(. != "")],
               url: "\($pub)/alerting/grafana/\(.uid)/view"}
        ] | sort_by(if .severity == "critical" then 0 elif .severity == "warning" then 1 else 2 end)}' <<<"$raw"
}

# Receive a file for SESSION over the terminal: the browser waits for the ready
# line, then sends exactly ceil(BYTES/3)*4 bytes of base64 as input.
cmd_upload() {
    [ $# -eq 3 ] || dd_die "usage: devdesk attach --upload SESSION FILENAME BYTES"
    local session=$1 name size=$3 dir dest b64len actual
    dd_valid_name "$session" || dd_die "invalid session name: $session"
    { [[ $size =~ ^[0-9]+$ ]] && [ "$size" -gt 0 ] && [ "$size" -le "$DEVDESK_UPLOAD_MAX" ]; } ||
        dd_die "file is empty or larger than $((DEVDESK_UPLOAD_MAX / 1048576)) MB"
    name=$(dd_safe_filename "$2")
    dir="$DEVDESK_STATE_DIR/uploads/$session"
    mkdir -p "$dir"
    find "$DEVDESK_STATE_DIR/uploads" -type f -mtime +7 -delete 2>/dev/null || true
    dest="$dir/$(date +%Y%m%d-%H%M%S)-$name"
    # shellcheck disable=SC2017 # integer ceil(size/3)*4: the base64 length, on purpose
    b64len=$(((size + 2) / 3 * 4))
    stty raw -echo 2>/dev/null || true
    printf 'DEVDESK-UPLOAD-READY\r\n'
    head -c "$b64len" | base64 -d >"$dest" 2>/dev/null || true
    stty sane 2>/dev/null || true
    actual=$(stat -c %s "$dest" 2>/dev/null || echo 0)
    if [ "$actual" != "$size" ]; then
        rm -f "$dest"
        dd_die "upload incomplete ($actual of $size bytes)"
    fi
    jq -cMn --arg p "$dest" '{ok: true, path: $p}'
}

ok_json() {
    printf '{"ok":true}\n'
}

cmd_attach() {
    if [ $# -eq 0 ]; then
        exec "$DEVDESK_LIBEXEC/devdesk-picker"
    fi
    case $1 in
    --list)
        [ $# -eq 1 ] || dd_die "--list takes no arguments"
        cmd_list
        return
        ;;
    --repo)
        shift
        cmd_repo "$@"
        return
        ;;
    --alerts)
        cmd_alerts
        return
        ;;
    --upload)
        shift
        cmd_upload "$@"
        return
        ;;
    --new | --rename | --end)
        local action=${1#--}
        shift
        "cmd_$action" "$@"
        ok_json
        return
        ;;
    -*) dd_die "unknown option: $1" ;;
    esac
    [ $# -eq 1 ] || dd_die "attach takes exactly one session name"
    local name=$1 dir args
    dd_valid_name "$name" || dd_die "invalid session name: $name"
    dd_ensure_server
    dir=$(dd_resolve_dir "$name")

    # Already inside a DevDesk pane: switch this client instead of nesting.
    local outer=${TMUX:-}
    if [ -n "$outer" ] && [ "${outer%%,*}" = "$DEVDESK_SOCKET" ]; then
        create_detached "$name" "$dir"
        exec tmux -N -S "$DEVDESK_SOCKET" switch-client -t "=$name"
    fi
    unset TMUX

    if ! dd_tmux has-session -t "=$name" 2>/dev/null; then
        dd_registry_set_dir "$name" "$dir"
    fi
    mapfile -d '' args < <(dd_new_session_args "$name" "$dir")
    # -A attaches if the session exists, so two tabs racing never create a duplicate.
    exec tmux -N -u -S "$DEVDESK_SOCKET" new-session -A "${args[@]}"
}

cmd=${1:-help}
[ $# -gt 0 ] && shift
case $cmd in
attach | a) cmd_attach "$@" ;;
new) cmd_new "$@" ;;
rename | mv) cmd_rename "$@" ;;
repo) cmd_repo "$@" ;;
alerts) cmd_alerts ;;
ls | list) cmd_ls ;;
--list) cmd_list ;;
end) cmd_end "$@" ;;
pick) exec "$DEVDESK_LIBEXEC/devdesk-picker" ;;
help | -h | --help) usage ;;
*)
    usage >&2
    exit 2
    ;;
esac