# SPDX-FileCopyrightText: 2024 Redict Contributors
# SPDX-FileCopyrightText: 2024 Salvatore Sanfilippo <antirez at gmail dot com>
#
# SPDX-License-Identifier: BSD-3-Clause
# SPDX-License-Identifier: LGPL-3.0-only

# Cluster helper functions

# Check if cluster configuration is consistent.
proc cluster_config_consistent {} {
    for {set j 0} {$j < [llength $::servers]} {incr j} {
        if {$j == 0} {
            set base_cfg [R $j cluster slots]
        } else {
            if {[R $j cluster slots] != $base_cfg} {
                return 0
            }
        }
    }

    return 1
}

# Check if cluster size is consistent.
proc cluster_size_consistent {cluster_size} {
    for {set j 0} {$j < $cluster_size} {incr j} {
        if {[CI $j cluster_known_nodes] ne $cluster_size} {
            return 0
        }
    }
    return 1
}

# Wait for cluster configuration to propagate and be consistent across nodes.
proc wait_for_cluster_propagation {} {
    wait_for_condition 50 100 {
        [cluster_config_consistent] eq 1
    } else {
        fail "cluster config did not reach a consistent state"
    }
}

# Wait for cluster size to be consistent across nodes.
proc wait_for_cluster_size {cluster_size} {
    wait_for_condition 1000 50 {
        [cluster_size_consistent $cluster_size] eq 1
    } else {
        fail "cluster size did not reach a consistent size $cluster_size"
    }
}

# Check that cluster nodes agree about "state", or raise an error.
proc wait_for_cluster_state {state} {
    for {set j 0} {$j < [llength $::servers]} {incr j} {
        wait_for_condition 100 50 {
            [CI $j cluster_state] eq $state
        } else {
            fail "Cluster node $j cluster_state:[CI $j cluster_state]"
        }
    }
}

# Default slot allocation for clusters, each master has a continuous block
# and approximately equal number of slots.
proc continuous_slot_allocation {masters} {
    set avg [expr double(16384) / $masters]
    set slot_start 0
    for {set j 0} {$j < $masters} {incr j} {
        set slot_end [expr int(ceil(($j + 1) * $avg) - 1)]
        R $j cluster addslotsrange $slot_start $slot_end
        set slot_start [expr $slot_end + 1]
    }
}

# Setup method to be executed to configure the cluster before the
# tests run.
proc cluster_setup {masters node_count slot_allocator code} {
    # Have all nodes meet
    if {$::tls} {
        set tls_cluster [lindex [R 0 CONFIG GET tls-cluster] 1]
    }
    if {$::tls && !$tls_cluster} {
        for {set i 1} {$i < $node_count} {incr i} {
            R 0 CLUSTER MEET [srv -$i host] [srv -$i pport]
        }         
    } else {
        for {set i 1} {$i < $node_count} {incr i} {
            R 0 CLUSTER MEET [srv -$i host] [srv -$i port]
        }
    }  

    $slot_allocator $masters

    wait_for_cluster_propagation

    # Setup master/replica relationships
    for {set i 0} {$i < $masters} {incr i} {
        set nodeid [R $i CLUSTER MYID]
        for {set j [expr $i + $masters]} {$j < $node_count} {incr j $masters} {
            R $j CLUSTER REPLICATE $nodeid
        }
    }

    wait_for_cluster_propagation
    wait_for_cluster_state "ok"

    uplevel 1 $code
}

# Start a cluster with the given number of masters and replicas. Replicas
# will be allocated to masters by round robin.
proc start_cluster {masters replicas options code {slot_allocator continuous_slot_allocation}} {
    set node_count [expr $masters + $replicas]

    # Set the final code to be the tests + cluster setup
    set code [list cluster_setup $masters $node_count $slot_allocator $code]

    # Configure the starting of multiple servers. Set cluster node timeout
    # aggressively since many tests depend on ping/pong messages. 
    set cluster_options [list overrides [list cluster-enabled yes cluster-ping-interval 100 cluster-node-timeout 3000]]
    set options [concat $cluster_options $options]

    # Cluster mode only supports a single database, so before executing the tests
    # it needs to be configured correctly and needs to be reset after the tests. 
    set old_singledb $::singledb
    set ::singledb 1
    start_multiple_servers $node_count $options $code
    set ::singledb $old_singledb
}

# Test node for flag.
proc cluster_has_flag {node flag} {
    expr {[lsearch -exact [dict get $node flags] $flag] != -1}
}

# Returns the parsed "myself" node entry as a dictionary.
proc cluster_get_myself id {
    set nodes [get_cluster_nodes $id]
    foreach n $nodes {
        if {[cluster_has_flag $n myself]} {return $n}
    }
    return {}
}

# Returns a parsed CLUSTER NODES output as a list of dictionaries.
proc get_cluster_nodes id {
    set lines [split [R $id cluster nodes] "\r\n"]
    set nodes {}
    foreach l $lines {
        set l [string trim $l]
        if {$l eq {}} continue
        set args [split $l]
        set node [dict create \
            id [lindex $args 0] \
            addr [lindex $args 1] \
            flags [split [lindex $args 2] ,] \
            slaveof [lindex $args 3] \
            ping_sent [lindex $args 4] \
            pong_recv [lindex $args 5] \
            config_epoch [lindex $args 6] \
            linkstate [lindex $args 7] \
            slots [lrange $args 8 end] \
        ]
        lappend nodes $node
    }
    return $nodes
}

# Returns 1 if no node knows node_id, 0 if any node knows it.
proc node_is_forgotten {node_id} {
    for {set j 0} {$j < [llength $::servers]} {incr j} {
        set cluster_nodes [R $j CLUSTER NODES]
        if { [string match "*$node_id*" $cluster_nodes] } {
            return 0
        }
    }
    return 1
}

# Isolate a node from the cluster and give it a new nodeid
proc isolate_node {id} {
    set node_id [R $id CLUSTER MYID]
    R $id CLUSTER RESET HARD
    # Here we additionally test that CLUSTER FORGET propagates to all nodes.
    set other_id [expr $id == 0 ? 1 : 0]
    R $other_id CLUSTER FORGET $node_id
    wait_for_condition 50 100 {
        [node_is_forgotten $node_id]
    } else {
        fail "CLUSTER FORGET was not propagated to all nodes"
    }
}

# Check if cluster's view of hostnames is consistent
proc are_hostnames_propagated {match_string} {
    for {set j 0} {$j < [llength $::servers]} {incr j} {
        set cfg [R $j cluster slots]
        foreach node $cfg {
            for {set i 2} {$i < [llength $node]} {incr i} {
                if {! [string match $match_string [lindex [lindex [lindex $node $i] 3] 1]] } {
                    return 0
                }
            }
        }
    }
    return 1
}

proc wait_node_marked_fail {ref_node_index instance_id_to_check} {
    wait_for_condition 1000 50 {
        [check_cluster_node_mark fail $ref_node_index $instance_id_to_check]
    } else {
        fail "Replica node never marked as FAIL ('fail')"
    }
}

proc wait_node_marked_pfail {ref_node_index instance_id_to_check} {
    wait_for_condition 1000 50 {
        [check_cluster_node_mark fail\? $ref_node_index $instance_id_to_check]
    } else {
        fail "Replica node never marked as PFAIL ('fail?')"
    }
}

proc check_cluster_node_mark {flag ref_node_index instance_id_to_check} {
    set nodes [get_cluster_nodes $ref_node_index]

    foreach n $nodes {
        if {[dict get $n id] eq $instance_id_to_check} {
            return [cluster_has_flag $n $flag]
        }
    }
    fail "Unable to find instance id in cluster nodes. ID: $instance_id_to_check"
}
